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Office of Scientific and Technical Information
Fundamental Research on Percussion Drilling: Improved rock mechanics analysis, advanced simulation technology, and full-scale laboratory investigations
Science Conference Proceedings (OSTI)
This report summarizes the research efforts on the DOE supported research project Percussion Drilling (DE-FC26-03NT41999), which is to significantly advance the fundamental understandings of the physical mechanisms involved in combined percussion and rotary drilling, and thereby facilitate more efficient and lower cost drilling and exploration of hard-rock reservoirs. The project has been divided into multiple tasks: literature reviews, analytical and numerical modeling, full scale laboratory testing and model validation, and final report delivery. Literature reviews document the history, pros and cons, and rock failure physics of percussion drilling in oil and gas industries. Based on the current understandings, a conceptual drilling model is proposed for modeling efforts. Both analytical and numerical approaches are deployed to investigate drilling processes such as drillbit penetration with compression, rotation and percussion, rock response with stress propagation, damage accumulation and failure, and debris transportation inside the annulus after disintegrated from rock. For rock mechanics modeling, a dynamic numerical tool has been developed to describe rock damage and failure, including rock crushing by compressive bit load, rock fracturing by both shearing and tensile forces, and rock weakening by repetitive compression-tension loading. Besides multiple failure criteria, the tool also includes a damping algorithm to dissipate oscillation energy and a fatigue/damage algorithm to update rock properties during each impact. From the model, Rate of Penetration (ROP) and rock failure history can be estimated. For cuttings transport in annulus, a 3D numerical particle flowing model has been developed with aid of analytical approaches. The tool can simulate cuttings movement at particle scale under laminar or turbulent fluid flow conditions and evaluate the efficiency of cutting removal. To calibrate the modeling efforts, a series of full-scale fluid hammer drilling tests, as well as single impact tests, have been designed and executed. Both Berea sandstone and Mancos shale samples are used. In single impact tests, three impacts are sequentially loaded at the same rock location to investigate rock response to repetitive loadings. The crater depth and width are measured as well as the displacement and force in the rod and the force in the rock. Various pressure differences across the rock-indentor interface (i.e. bore pressure minus pore pressure) are used to investigate the pressure effect on rock penetration. For hammer drilling tests, an industrial fluid hammer is used to drill under both underbalanced and overbalanced conditions. Besides calibrating the modeling tool, the data and cuttings collected from the tests indicate several other important applications. For example, different rock penetrations during single impact tests may reveal why a fluid hammer behaves differently with diverse rock types and under various pressure conditions at the hole bottom. On the other hand, the shape of the cuttings from fluid hammer tests, comparing to those from traditional rotary drilling methods, may help to identify the dominant failure mechanism that percussion drilling relies on. If so, encouraging such a failure mechanism may improve hammer performance. The project is summarized in this report. Instead of compiling the information contained in the previous quarterly or other technical reports, this report focuses on the descriptions of tasks, findings, and conclusions, as well as the efforts on promoting percussion drilling technologies to industries including site visits, presentations, and publications. As a part of the final deliveries, the 3D numerical model for rock mechanics is also attached.
Michael S. Bruno
Isotopic Analysis- Rock | Open Energy Information
Open Energy Info (EERE)
Isotopic Analysis- Rock Isotopic Analysis- Rock Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Isotopic Analysis- Rock Details Activities (13) Areas (11) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Water rock interaction Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png Isotopic Analysis- Rock: Isotopes are atoms of the same element that have different numbers of neutrons. An isotopic analysis looks at a particular isotopic element(s) in a given system, while the conditions which increase/decrease the number of neutrons are well understood and measurable.
Rock Lab Analysis | Open Energy Information
Rock Lab Analysis Rock Lab Analysis Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Rock Lab Analysis Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Lab Analysis Techniques Information Provided by Technique Lithology: Core and cuttings analysis is done to define lithology. Water rock interaction. Can determine detailed information about rock composition and morphology. Density of different lithologic units. Rapid and unambiguous identification of unknown minerals.[1] Stratigraphic/Structural: Core analysis can locate faults or fracture networks. Oriented core can give additional important information on anisotropy. Historic structure and deformation of land.
Carbonation Mechanism of Reservoir Rock by Supercritical Carbon Dioxide
Carbonation Mechanism of Reservoir Rock by Supercritical Carbon Dioxide Carbonation Mechanism of Reservoir Rock by Supercritical Carbon Dioxide Geothermal Lab Call Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Carbonation Mechanism of Reservoir Rock by Supercritical Carbon Dioxide Project Type / Topic 1 Laboratory Call for Submission of Applications for Research, Development and Analysis of Geothermal Technologies Project Type / Topic 2 Supercritical Carbon Dioxide / Reservoir Rock Chemical Interactions Project Description Supercritical CO2 is currently becoming a more common fluid for extracting volatile oil and fragrance compounds from various raw materials that are used in perfumery. Furthermore, its use as a heat transmission fluid is very attractive because of the greater uptake capability of heat from hot reservoir rock, compared with that of water. However, one concern was the reactivity of CO2 with clay and rock minerals in aqueous and non-aqueous environments. So if this reaction leads to the formation of water-soluble carbonates, such formation could be detrimental to the integrity of wellbore infrastructure.
Rock mechanics contributions from defense programs
SciTech Connect
An attempt is made at illustrating the many contributions to rock mechanics from US defense programs, over the past 30-plus years. Large advances have been achieved in the technology-base area covering instrumentation, material properties, physical modeling, constitutive relations and numerical simulations. In the applications field, much progress has been made in understanding and being able to predict rock mass behavior related to underground explosions, cratering, projectile penetration, and defense nuclear waste storage. All these activities stand on their own merit as benefits to national security. But their impact is even broader, because they have found widespread applications in the non-defense sector; to name a few: the prediction of the response of underground structures to major earthquakes, the physics of the earth`s interior at great depths, instrumentation for monitoring mine blasting, thermo-mechanical instrumentation useful for civilian nuclear waste repositories, dynamic properties of earthquake faults, and transient large-strain numerical modeling of geological processes, such as diapirism. There is not pretense that this summary is exhaustive. It is meant to highlight success stories representative of DOE and DOD geotechnical activities, and to point to remaining challenges.
Heuze, F.E.
Mechanical and acoustic properties of weakly cemented granular rocks
This paper presents the results of laboratory measurements on the mechanical and acoustic properties of weakly cemented granular rock. Artificial rock samples were fabricated by cementing sand and glass beads with sodium silicate binder. During uniaxial compression tests, the rock samples showed stress-strain behavior which was more similar to that of soils than competent rocks, exhibiting large permanent deformations with frictional slip. The mechanical behavior of the samples approached that of competent rocks as the amount of binder was increased. For very weak samples, acoustic waves propagating in these rocks showed very low velocities of less than 1000 m/sec for compressional waves. A borehole made within this weakly cemented rock exhibited a unique mode of failure that is called ''anti-KI mode fracture'' in this paper. The effect of cementation, grain type, and boundary conditions on this mode of failure was also examined experimentally.
Nakagawa, S.; Myer, L.R.
Definition: Isotopic Analysis- Rock | Open Energy Information
Isotopic Analysis- Rock Isotopic Analysis- Rock Jump to: navigation, search Dictionary.png Isotopic Analysis- Rock Isotopes are atoms of the same element that have different numbers of neutrons. An isotopic analysis looks at a particular isotopic element(s) in a given system, while the conditions which increase/decrease the number of neutrons are well understood and measurable.[1] View on Wikipedia Wikipedia Definition References ↑ http://wwwrcamnl.wr.usgs.gov/isoig/isopubs/itchch2.html Ret LikeLike UnlikeLike You like this.Sign Up to see what your friends like. rieved from "http://en.openei.org/w/index.php?title=Definition:Isotopic_Analysis-_Rock&oldid=687702" Category: Definitions What links here Related changes Special pages Printable version Permanent link Browse properties
Seismic and Acoustic Investigations of Rock Fall Initiation, Processes, and Mechanics
E-Print Network (OSTI)
38 th �U.S. � Rock �Mechanics �Symposium. �1321-�?1333. �38 th �U.S. �Rock �Mechanics �Symposium, �1313-�?1320. �Introduction � to � Rock � Mechanics. � John � Wiley � and �
Zimmer, Valerie Louise
Coupled hydro-mechanical processes in crytalline rock and in induratedand plastic clays: A comparative discussion
at Grimsel. In Coupled Thermo-Hydro- Mechanical-ChemicalCOUPLED HYDRO-MECHANICAL PROCESSES IN CRYTALLINE ROCK AND IN
Tsang, Chin-Fu; Blumling, Peter; Bernier, Frederic
Category:Rock Lab Analysis | Open Energy Information
source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Category Edit History Facebook icon Twitter icon » Category:Rock Lab Analysis Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Rock Lab Analysis page? For detailed information on exploration techniques, click here. Category:Rock Lab Analysis Add.png Add a new Rock Lab Analysis Technique Pages in category "Rock Lab Analysis" The following 9 pages are in this category, out of 9 total. C Core Analysis Cuttings Analysis I Isotopic Analysis- Rock O Over Core Stress P Paleomagnetic Measurements Petrography Analysis R Rock Density X X-Ray Diffraction (XRD) X-Ray Fluorescence (XRF)
Isotopic Analysis- Rock At Long Valley Caldera Area (Smith &...
Isotopic Analysis- Rock At Long Valley Caldera Area (Smith & Suemnicht, 1991) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis-...
The purpose of this Analysis and Model Report (AMR) is to document Rock Properties Model (RPM) 3.1 with regard to input data, model methods, assumptions, uncertainties and limitations of model results, and qualification status of the model. The report also documents the differences between the current and previous versions and validation of the model. The rock properties models are intended principally for use as input to numerical physical-process modeling, such as of ground-water flow and/or radionuclide transport. The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. This work was conducted in accordance with the following planning documents: WA-0344, ''3-D Rock Properties Modeling for FY 1998'' (SNL 1997, WA-0358), ''3-D Rock Properties Modeling for FY 1999'' (SNL 1999), and the technical development plan, Rock Properties Model Version 3.1, (CRWMS M&O 1999c). The Interim Change Notice (ICNs), ICN 02 and ICN 03, of this AMR were prepared as part of activities being conducted under the Technical Work Plan, TWP-NBS-GS-000003, ''Technical Work Plan for the Integrated Site Model, Process Model Report, Revision 01'' (CRWMS M&O 2000b). The purpose of ICN 03 is to record changes in data input status due to data qualification and verification activities. These work plans describe the scope, objectives, tasks, methodology, and implementing procedures for model construction. The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The work scope for this activity consists of the following: (1) Conversion of the input data (laboratory measured porosity data, x-ray diffraction mineralogy, petrophysical calculations of bound water, and petrophysical calculations of porosity) for each borehole into stratigraphic coordinates; (2) Re-sampling and merging of data sets; (3) Development of geostatistical simulations of porosity; (4) Generation of derivative property models via linear coregionalization with porosity; (5) Post-processing of the simulated models to impart desired secondary geologic attributes and to create summary and uncertainty models; and (6) Conversion of the models into real-world coordinates. The conversion to real world coordinates is performed as part of the integration of the RPM into the Integrated Site Model (ISM) 3.1; this activity is not part of the current analysis. The ISM provides a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site and consists of three components: (1) Geologic Framework Model (GFM); (2) RPM, which is the subject of this AMR; and (3) Mineralogic Model. The interrelationship of the three components of the ISM and their interface with downstream uses are illustrated in Figure 1. Figure 2 shows the geographic boundaries of the RPM and other component models of the ISM.
Clinton Lum
New Equipment of Distinguishing Rock from Coal Based on Statistical Analysis of Fast Fourier Transform
A new equipment of distinguishing rock from coal based on statistical analysis of Fast Fourier Transform (FFT) is invented which can be used in the mechanized caving coal locales. First, eight groups of sound signals which had been measured during caving ... Keywords: Threshold of Distinguishing Rock from Coal, Fast Fourier Transform (FFT), Frequency Energy Variance, Frequency Energy Ratio
Gu Tao; Li Xu
Definition: Rock Lab Analysis | Open Energy Information
to core recovered from boreholes. They typically involve measuring the physical and chemical properties of the rock. Physical properties include density, elastic modulus, seismic...
Isotopic Analysis- Rock At Coso Geothermal Area (1984) | Open Energy
Analysis- Rock At Coso Geothermal Area (1984) Analysis- Rock At Coso Geothermal Area (1984) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Rock At Coso Geothermal Area (1984) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Isotopic Analysis- Rock Activity Date 1984 Usefulness not indicated DOE-funding Unknown Exploration Basis To analyze evidence for crustal interaction and compositional zonation in the source regions of Pleistocene basaltic and rhyolitic magmas of the Coso volcanic field Notes The isotopic compositions of Pb and Sr in Pleistocene basalt, high-silica rhyolite, and andesitic inclusions in rhyolite of the Coso volcanic field indicate that these rocks were derived from different levels of compositionally zoned magmatic systems. The two earliest rhyolites probably
Rock Mechanics and Enhanced Geothermal Systems: A DOE-sponsored Workshop to Explore Research Needs
DOE Green Energy (OSTI)
This workshop on rock mechanics and enhanced geothermal systems (EGS) was held in Cambridge, Mass., on June 20-21 2003, before the Soil and Rock America 2003 International Conference at MIT. Its purpose was to bring together experts in the field of rock mechanics and geothermal systems to encourage innovative thinking, explore new ideas, and identify research needs in the areas of rock mechanics and rock engineering applied to enhanced geothermal systems. The agenda is shown in Appendix A. The workshop included experts in the fields of rock mechanics and engineering, geological engineering, geophysics, drilling, the geothermal energy production from industry, universities and government agencies, and laboratories. The list of participants is shown is Appendix B. The first day consisted of formal presentations. These are summarized in Chapter 1 of the report. By the end of the first day, two broad topic areas were defined: reservoir characterization and reservoir performance. Working groups were formed for each topic. They met and reported in plenary on the second day. The working group summaries are described in Chapter 2. The final session of the workshop was devoted to reaching consensus recommendations. These recommendations are given in Chapter 3. That objective was achieved. All the working group recommendations were considered and, in order to arrive at a practical research agenda usable by the workshop sponsors, workshop recommendations were reduced to a total of seven topics. These topics were divided in three priority groups, as follows. First-priority research topics (2): {sm_bullet} Define the pre-existing and time-dependent geometry and physical characteristics of the reservoir and its fracture network. That includes the identification of hydraulically controlling fractures. {sm_bullet} Characterize the physical and chemical processes affecting the reservoir geophysical parameters and influencing the transport properties of fractures. Incorporate those processes in reservoir simulators. Second-priority research topics (4): {sm_bullet} Implement and proof-test enhanced fracture detection geophysical methods, such as 3-D surface seismics, borehole seismics, and imaging using earthquake data. {sm_bullet} Implement and proof-test enhanced stress measurement techniques, such as borehole breakout analysis, tilt-meters, and earthquake focal mechanism analysis. {sm_bullet} Implement and proof-test high-temperature down-hole tools for short-term and long-term diagnostics, such as borehole imaging, geophone arrays, packers, and electrical tools.
Francois Heuze; Peter Smeallie; Derek Elsworth; Joel L. Renner
Carbonation Mechanism of Reservoir Rock by Supercritical Carbon...
Technologies Project Type Topic 2 Supercritical Carbon Dioxide Reservoir Rock Chemical Interactions Project Description Supercritical CO2 is currently becoming a more...
Isotopic Analysis- Rock At Coso Geothermal Area (1997) | Open Energy
Rock At Coso Geothermal Area (1997) Rock At Coso Geothermal Area (1997) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Rock At Coso Geothermal Area (1997) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Isotopic Analysis- Rock Activity Date 1997 Usefulness useful DOE-funding Unknown Exploration Basis Determine a major lithospheric boundary Notes Sr and Nd isotope ratios of Miocene-Recent basalts in eastern California, when screened for crustal contamination, vary dramatically and indicate the presence of a major lithospheric boundary that is not obvious from surface geology. Isotope ratios from the Coso field form a bull's-eye pattern with very low 87Sr/86Sr (0.7033) centered just south of the geothermal area. The
A rock mechanics perspective on the effects of hard rock workings in close proximity to overlying coal seams
Mining in the Coalfields has been ongoing for many years, however prior to the discovery of coal, Gold was being mined in the form of the Kimberley Reef. Today it is the coal that has our interest and is the primary mineral being extracted from the ground. ... Keywords: mining, pillars, rock mechanics, slabbing, stress
K. Naidoo; C. Dekker
Isotopic Analysis- Rock At Valles Caldera - Sulphur Springs Area
source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Isotopic Analysis- Rock At Valles Caldera - Sulphur Springs Area (Woldegabriel & Goff, 1992) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Rock At Valles Caldera - Sulphur Springs Area (Woldegabriel & Goff, 1992) Exploration Activity Details Location Valles Caldera - Sulphur Springs Area Exploration Technique Isotopic Analysis- Rock Activity Date Usefulness not indicated DOE-funding Unknown Notes Useful for age determinations - not indicated is useful for exploration. References Giday WoldeGabriel, Fraser Goff (1992) K-Ar Dates Of Hydrothermal
Mechanisms of heat exchange between water and rock in karst conduits
Mechanisms of heat exchange between water and rock in karst conduits M. D. Covington,1 A. J water quality, have explored the mechanisms for heat transport and heat exchange in surface streams flux can be significant. In contrast, convective heat exchange through the conduit air is often
Saar, Martin O.
Limitations of rock mechanics in energy-resource recovery and development
Rock-mechanics problems which limit energy-resource recovery and development are assessed. The most serious limitations were found in the fields of geothermal exploration, mining and in-situ recovery, nuclear-waste disposal, oil and gas recovery, underground storage, and under-ocean tunneling. Recommendations include research to determine and predict porosity, permeability, and fluid flow in situ; research to develop better methods for determining and obtaining shallow and deep in situ stresses; research to improve the ability to map fracture patterns, particularly major fractures and faults, at depth; research to improve the understanding of rock-fragmentation processes for increasing the effectiveness of drilling and excavation systems; research to increase understanding of the relation of laboratory-measured quantities to in situ conditions; and research to provide the thermophysical and thermomechanical properties of rock, including fractured rock. (JRD)
Not Available
Comparison and analysis of reservoir rocks and related clays
A series of instrumental and chemical analyses was made on sedimentary rocks to determine the surface chemical properties of sedimentry rocks and the physical characteristic of the pores. A scanning electron microscope (SEM) with energy dispersive X-ray analytic capability was used to study the morphology of the samples, surface mineral composition and type and location of clays, and to obtain a qualitative estimate of the pore sizes. A centrifuge was used to determine the pore size distributions which are correlated with SEM observations. An atomic absorption spectrophotometer equipped with an inductively coupled plasma for complete spectral analysis was used to obtain analyses of the rocks, clays, and effluents from ion exchange tests. Two of the results are as follows: (1) Sweetwater gas sands have a bimodal pore size distribution composed of pores with a mean diameter of 0.2 microns which is attributed to intergranular spaces and cracks in the expanded laborboratory sample but which will be close under the pressure of the overburden formations, and these Sweetwater sands have a distribution of pores at 2 microns which are solution vugs rather than intergranular porosity since the sand grains are completely packed together with the cementing material due to the high overburden pressures; and (2) Ion-exchange capacities of two rocks were 5.3 meq/kg and 18.0 meq/kg, and the surface areas were 0.9 m/sup 2//g and 2.30 m/sup 2//g, respectively, even though each had almost identical mineral composition, clay type and quantity, and permeability. 7 references, 12 figures, 3 tables.
Crocker, M.E.; Donaldson, E.C.; Marchin, L.M.
Tensor analysis of spatial mechanisms
The position analysis of a general four-bar spatial mechanism is developed using tensor notation and operations. To exemplify the convenience of tensors in kinematic analysis the solution is obtained for a mechanism containing two revolute pairs of links ...
C. Y. Ho
A Mechanism of Improved Oil Recovery by Low-Salinity Waterflooding in Sandstone Rock
Injection of low-salinity water showed high potentials in improving oil recovery when compared to high-salinity water. However, the optimum water salinity and conditions are uncertain, due to the lack of understanding the mechanisms of fluid-rock interactions. The main objective of this study is to examine the potential and efficiency of low-salinity water in secondary and tertiary oil recovery for sandstone reservoirs. Similarly, this study aims to help in understanding the dominant mechanisms that aid in improving oil recovery by low-salinity waterflooding. Furthermore, the impact of cation type in injected brines on oil recovery was investigated. Coreflood experiments were conducted to determine the effect of water salinity and chemistry on oil recovery in the secondary and tertiary modes. The contact angle technique was used to study the impact of water salinity and composition on rock wettability. Moreover, the zeta potential at oil/brine and brine/rock interfaces was measured to explain the mechanism causing rock wettability alteration and improving oil recovery. Deionized water and different brines (from 500 to 174,000 mg/l), as well as single cation solutions were tested. Two types of crude oil with different properties and composition were used. Berea sandstone cores were utilized in the coreflood experiments. Coreflood tests indicated that injection of deionized water in the secondary mode resulted in significant oil recovery, up to 22% improvement, compared to seawater flooding. However, no more oil was recovered in the tertiary mode. In addition, injection of NaCl solution increased the oil recovery compared to injection of CaCl2 or MgCl2 at the same concentration. Contact angle results demonstrated that low-salinity water has an impact on the rock wettability; the more reduction in water salinity, the more a water-wet rock surface is produced. In addition, NaCl solutions made the rock more water-wet compared to CaCl2 or MgCl2 at the same concentration. Low-salinity water and NaCl solutions showed a highly negative charge at rock/brine and oil/brine interfaces by zeta potential measurements, which results in greater repulsive forces between the oil and rock surface. This leads to double-layer expansion and water-wet systems. These results demonstrate that the double-layer expansion is a primary mechanism of improving oil recovery when water chemical composition is manipulated.
Nasralla, Ramez
The research during this project has concentrated on developing a correlation between rock deformation mechanisms and their acoustic velocity signature. This has included investigating: (1) the acoustic signature of drained and undrained unconsolidated sands, (2) the acoustic emission signature of deforming high porosity rocks (in comparison to their low porosity high strength counterparts), (3) the effects of deformation on anisotropic elastic and poroelastic moduli, and (4) the acoustic tomographic imaging of damage development in rocks. Each of these four areas involve triaxial experimental testing of weak porous rocks or unconsolidated sand and involves measuring acoustic properties. The research is directed at determining the seismic velocity signature of damaged rocks so that 3-D or 4-D seismic imaging can be utilized to image rock damage. These four areas of study are described in the report: (1) Triaxial compression experiments have been conducted on unconsolidated Oil Creek sand at high confining pressures. (2) Initial experiments on measuring the acoustic emission activity from deforming high porosity Danian chalk were accomplished and these indicate that the AE activity was of a very low amplitude. (3) A series of triaxial compression experiments were conducted to investigate the effects of induced stress on the anisotropy developed in dynamic elastic and poroelastic parameters in rocks. (4) Tomographic acoustic imaging was utilized to image the internal damage in a deforming porous limestone sample. Results indicate that the deformation damage in rocks induced during laboratory experimentation can be imaged tomographically in the laboratory. By extension the results also indicate that 4-D seismic imaging of a reservoir may become a powerful tool for imaging reservoir deformation (including imaging compaction and subsidence) and for imaging zones where drilling operation may encounter hazardous shallow water flows.
Thurman E. Scott, Jr.; Younane Abousleiman
Analysis of Thermally Induced Changes in Fractured Rock Permeability during Eight Years of Heating and Cooling at the Yucca Mountain Drift Scale Test
and Cooling at the Yucca Mountain Drift Scale Test J.mechanical analysis of the Yucca Mountain Drift Scale Test �scale heater test at Yucca Mountain, Nevada, USA. Int J Rock
Rutqvist, J.
Borehole temperature survey analysis hot dry rock geothermal reservoir
The Los Alamos Scientific Laboratory (LASL) has been actively investigating the potential for extracting geothermal energy from hot dry rock. A man-made geothermal reservoir has been formed at the Fenton Hill Test Site in northern New Mexico. The 10-MW (thermal) prototype energy extraction circulation loop has been completed and has been continuously operating since January 28 of this year. The performance of the Phase I 1000-h circulation experiment would establish technological assessment of the particular hot dry rock geothermal reservoir. The major parameters of interest include equipment operations, geochemistry, water loss, and reservoir thermal drawdown. Temperature measurements were used extensively as one method to study the man-made geothermal reservoir. The temperature probe is one of the less complex wellbore survey tools that is readily fielded to allow on-line analysis of changing conditions in the hydraulic-fracture system. Several downhole temperature instruments have been designed and fabricated for use in the GT-2/EE-1 wellbores.
Dennis, B.R.; Murphy, H.D.
systems �and �rock �fall �source �and �impact �areas, �it �possible �to �a � rock � fall � source � area � in � the �possible �to �a �rock � fall �source �area. � �There �are �
A numerical model of hydro-thermo-mechanical coupling in a fractured rock mass
Coupled hydro-thermo-mechanical codes with the ability to model fractured materials are used for predicting groundwater flow behavior in fractured aquifers containing thermal sources. The potential applications of such a code include the analysis of groundwater behavior within a geothermal reservoir. The capability of modeling hydro-thermo systems with a dual porosity, fracture flow model has been previously developed in the finite element code, FEHM. FEHM has been modified to include stress coupling with the dual porosity feature. FEHM has been further developed to implicitly couple the dependence of fracture hydraulic conductivity on effective stress within two dimensional, saturated aquifers containing fracture systems. The cubic law for flow between parallel plates was used to model fracture permeability. The Bartin-Bandis relationship was used to determine the fracture aperture within the cubic law. The code used a Newton Raphson iteration to implicitly solve for six unknowns at each node. Results from a model of heat flow from a reservoir to the moving fluid in a single fracture compared well with analytic results. Results of a model showing the increase in fracture flow due to a single fracture opening under fluid pressure compared well with analytic results. A hot dry rock, geothermal reservoir was modeled with realistic time steps indicating that the modified FEHM code does successfully model coupled flow problems with no convergence problems.
Bower, K.M.
Mechanically weak formations, such as chalks, high porosity sandstones, and marine sediments, pose significant problems for oil and gas operators. Problems such as compaction, subsidence, and loss of permeability can affect reservoir production operations. For example, the unexpected subsidence of the Ekofisk chalk in the North Sea required over one billion dollars to re-engineer production facilities to account for losses created during that compaction (Sulak 1991). Another problem in weak formations is that of shallow water flows (SWF). Deep water drilling operations sometimes encounter cases where the marine sediments, at shallow depths just below the seafloor, begin to uncontrollably flow up and around the drill pipe. SWF problems created a loss of $150 million for the Ursa development project in the U.S. Gulf Coast SWF (Furlow 1998a,b; 1999a,b). The goal of this project is to provide a database on both the rock mechanical properties and the geophysical properties of weak rocks and sediments. These could be used by oil and gas companies to detect, evaluate, and alleviate potential production and drilling problems. The results will be useful in, for example, pre-drill detection of events such as SWF's by allowing a correlation of seismic data (such as hazard surveys) to rock mechanical properties. The data sets could also be useful for 4-D monitoring of the compaction and subsidence of an existing reservoir and imaging the zones of damage. During the second quarter of the project the research team has: (1) completed acoustic sensor construction, (2) conducted reconnaissance tests to map the deformational behaviors of the various rocks, (3) developed a sample assembly for the measurement of dynamic elastic and poroelastic parameters during triaxial testing, and (4) conducted a detailed review of the scientific literature and compiled a bibliography of that review. During the first quarter of the project the research team acquired several rock types for testing including: (a) Danian chalk, (b) Cordoba Cream limestone, (c) Indiana limestone, (d) Ekofisk chalk, (e) Oil Creek sandstone, (f) unconsolidated Oil Creek sand, and (g) unconsolidated Brazos river sand. During the second quarter experiments were begun on these rock types. A series of reconnaissance experiments have been carried out on all but the Ekofisk (for which there is a preliminary data set already inhouse). A series of triaxial tests have been conducted on the Danian chalk, the Cordoba Cream limestone, the Indiana limestone, and sand samples to make a preliminary determination of the deformational mechanisms present in these samples.
Thurman E. Scott, Jr., Ph.D.; Younane Abousleiman, Ph.D.; Musharraf Zaman, Ph.D., P.E.
The oil and gas industry has encountered significant problems in the production of oil and gas from weak rocks (such as chalks and limestones) and from unconsolidated sand formations. Problems include subsidence, compaction, sand production, and catastrophic shallow water sand flows during deep water drilling. Together these cost the petroleum industry hundreds of millions of dollars annually. The goals of this first quarterly report is to document the progress on the project to provide data on the acoustic imaging and mechanical properties of soft rock and marine sediments. The project is intended to determine the geophysical (acoustic velocities) rock properties of weak, poorly cemented rocks and unconsolidated sands. In some cases these weak formations can create problems for reservoir engineers. For example, it cost Phillips Petroleum 1 billion dollars to repair of offshore production facilities damaged during the unexpected subsidence and compaction of the Ekofisk Field in the North Sea (Sulak 1991). Another example is the problem of shallow water flows (SWF) occurring in sands just below the seafloor encountered during deep water drilling operations. In these cases the unconsolidated sands uncontrollably flow up around the annulus of the borehole resulting in loss of the drill casing. The $150 million dollar loss of the Ursa development project in the U.S. Gulf Coast resulted from an uncontrolled SWF (Furlow 1998a,b; 1999a,b). The first three tasks outlined in the work plan are: (1) obtain rock samples, (2) construct new acoustic platens, (3) calibrate and test the equipment. These have been completed as scheduled. Rock Mechanics Institute researchers at the University of Oklahoma have obtained eight different types of samples for the experimental program. These include: (a) Danian Chalk, (b) Cordoba Cream Limestone, (c) Indiana Limestone, (d) Ekofisk Chalk, (e) Oil Creek Sandstone, (f) unconsolidated Oil Creek sand, and (g) unconsolidated Brazos river sand. These weak rocks and sands are intended to represent analogs to the formations that present oil and gas engineers with problems during oil and gas production and drilling operations. A series of new axial acoustic sensors have been constructed (and tested) to allow measurement of compressional and shear wave velocities during high pressure triaxial tests on these weak rock and sand samples. In addition, equipment to be utilized over the next 18 months of the project have tested and calibrated. These include the load frames, triaxial pressure cells, pressure sensors, load cells, extensometers, and oscilloscopes have been calibrated and tested. The multichannel acoustic emission and acoustic pulse transmission systems have also been tested. Graduate research assistant, research faculty, and the laboratory technician have begun Tasks 4 and 5 which involve preparing the sand samples and rock samples for testing. The construction of the lateral acoustic sensors has also been started during this quarter as outlined in the project timeline. With the equipment having been tested and calibrated, and the samples now being prepared, the experiments are on schedule to be started in April, 2001.
Thurman E. Scott, Jr., Ph.D.; Musharraf Zaman, Ph.D.; Younane Abousleiman, Ph.D.
Mechanical and transport properties of rocks at high temperatures and pressures. Task III. Mechanical properties of rocks at high temperatures and pressures. Final report, 1 March 1980-29 February 1984
This report summarizes the research performed to gain a fundamental understanding of the mechanical and transport properties of rocks under confining pressure and elevated temperature. There have been many contributions to our understanding of the mechanical behavior or rocks at high temperatures and pressures, but perhaps the three most outstanding contributions are the data which: (a) have helped to demonstrate the scientific feasibility of energy extraction from buried magma by assessing the likelihood of the rock mass to support stable boreholes at the pressures, temperatures (to partial melting), and aqueous conditions apt to occur in crystalline rocks above buried magma chambers; (b) have demonstrated that crystalline rocks deform primarily by brittle fracture when deformed at effective confining pressures to 200 MPa and temperatures to partial melting (to >1000/sup 0/C), water-saturated or room-dry, and in constant strain rate tests (e dot = 10/sup -4/-10/sup -7//sec) or in creep tests; and (c) have shown that under these same conditions the time-dependent behavior of the rocks in the quasi-steady state regime is well described by the flow law: e dot = Asigma/sup n/exp(-Q/RT) - a formulation previously thought to be applicable to rocks deforming primarily by crystal plasticity. This result suggests that fracture is also a time-dependent, thermally-activated process.
Friedman, M.; Handin, J.; Bauer, S.J.
Isotopic Analysis- Rock At Valles Caldera - Sulphur Springs Area (Ito &
source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Isotopic Analysis- Rock At Valles Caldera - Sulphur Springs Area (Ito & Tanaka, 1995) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Rock At Valles Caldera - Sulphur Springs Area (Ito & Tanaka, 1995) Exploration Activity Details Location Valles Caldera - Sulphur Springs Area Exploration Technique Isotopic Analysis- Rock Activity Date Usefulness not indicated DOE-funding Unknown References Hisatoshi Ito, Kazuhiro Tanaka (1995) Insights On The Thermal History Of The Valles Caldera, New Mexico- Evidence From Zircon
Isotopic Analysis- Rock At Long Valley Caldera Area (Smith & Suemnicht,
Isotopic Analysis- Rock At Long Valley Caldera Area (Smith & Suemnicht, Isotopic Analysis- Rock At Long Valley Caldera Area (Smith & Suemnicht, 1991) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Rock At Long Valley Caldera Area (Smith & Suemnicht, 1991) Exploration Activity Details Location Long Valley Caldera Area Exploration Technique Isotopic Analysis- Rock Activity Date Usefulness useful DOE-funding Unknown Notes This oxygen isotope and fluid inclusion study has allowed us to determine the pathways of fluid circulation, set limits on the thermal regime, and link the source of the heat to prolonged volcanic activity. At shallow depths in the caldera References Brian M. Smith, Gene A. Suemnicht (1991) Oxygen Isotope Evidence For Past And Present Hydrothermal Regimes Of Long Valley Caldera, California
Development of enhanced geothermal systems (EGS) will require creation of a reservoir of sufficient volume to enable commercial-scale heat transfer from the reservoir rocks to the working fluid. A key assumption associated with reservoir creation/stimulation is that sufficient rock volumes can be hydraulically fractured via both tensile and shear failure, and more importantly by reactivation of naturally existing fractures (by shearing), to create the reservoir. The advancement of EGS greatly depends on our understanding of the dynamics of the intimately coupled rock-fracture-fluid-heat system and our ability to reliably predict how reservoirs behave under stimulation and production. Reliable performance predictions of EGS reservoirs require accurate and robust modeling for strongly coupled thermal-hydrological-mechanical (THM) processes. Conventionally, these types of problems have been solved using operator-splitting methods, usually by coupling a subsurface flow and heat transport simulators with a solid mechanics simulator via input files. An alternative approach is to solve the system of nonlinear partial differential equations that govern multiphase fluid flow, heat transport, and rock mechanics simultaneously, using a fully coupled, fully implicit solution procedure, in which all solution variables (pressure, enthalpy, and rock displacement fields) are solved simultaneously. This paper describes numerical simulations used to investigate the poro- and thermal- elastic effects of working fluid injection and thermal energy extraction on the properties of the fractures and rock matrix of a hypothetical EGS reservoir, using a novel simulation software FALCON (Podgorney et al., 2011), a finite element based simulator solving fully coupled multiphase fluid flow, heat transport, rock deformation, and fracturing using a global implicit approach. Investigations are also conducted on how these poro- and thermal-elastic effects are related to fracture permeability evolution.
Robert Podgorney; Chuan Lu; Hai Huang
U.S. National Committee for Rock Mechanics; and Conceptual model of fluid infiltration in fractured media. Project summary, July 28, 1997--July 27, 1998
The title describes the two tasks summarized in this report. The remainder of the report contains information on meetings held or to be held on the subjects. The US National Committee for Rock Mechanics (USNC/RM) provides for US participation in international activities in rock mechanics, principally through adherence to the International Society for Rock Mechanics (ISRM). It also keeps the US rock mechanics community informed about new programs directed toward major areas of national concern in which rock mechanics problems represent critical or limiting factors, such as energy resources, excavation, underground storage and waste disposal, and reactor siting. The committee also guides or produces advisory studies and reports on problem areas in rock mechanics. A new panel under the auspices of the US National Committee for Rock Mechanics has been appointed to conduct a study on Conceptual Models of Fluid Infiltration in Fractured Media. The study has health and environmental applications related to the underground flow of pollutants through fractured rock in and around mines and waste repositories. Support of the study has been received from the US Nuclear Regulatory Commission and the Department of Energy`s Yucca Mountain Project Office. The new study builds on the success of a recent USNC/RM report entitled Rock Fractures and Fluid Flow: Contemporary Understanding and Applications (National Academy Press, 1996, 551 pp.). A summary of the new study is provided.
Mechanical properties of rocks at high temperatures and pressures: Final report
During the final year of the grant, we have investigated (1) why the strengths of rocks decrease with increasing temperature and in the presence of water through study of the fracture process in Westerly granite and Sioux quartzite specimens deformed in extension (some in true tension), (2) frictional strengths of rocks at high temperatures, (3) the stability of boreholes in fractured rock, and (4) slip in biotite single crystals (in that biotite is probably the weakest and most ductile of the common constituents of crystalline rocks.
Friedman, M.; Bauer, S.J.; Chester, F.M.; Handin, J.; Hopkins, T.W.; Johnson, B.; Kronenberg, A.K.; Mardon, D.; Russell, J.E.
Cell body rocking is a dominant mechanism for flagellar synchronization in a swimming algae
The unicellular green algae Chlamydomonas swims with two flagella, which can synchronize their beat. Synchronized beating is required to swim both fast and straight. A long-standing hypothesis proposes that synchronization of flagella results from hydrodynamic coupling, but the details are not understood. Here, we present realistic hydrodynamic computations and high-speed tracking experiments of swimming cells that show how a perturbation from the synchronized state causes rotational motion of the cell body. This rotation feeds back on the flagellar dynamics via hydrodynamic friction forces and rapidly restores the synchronized state in our theory. We calculate that this `cell body rocking' provides the dominant contribution to synchronization in swimming cells, whereas direct hydrodynamic interactions between the flagella contribute negligibly. We experimentally confirmed the coupling between flagellar beating and cell body rocking predicted by our theory. We propose that the interplay of flagellar beating and hydrodynamic forces governs swimming and synchronization in Chlamydomonas.
Veikko Geyer; Frank J�licher; Jonathon Howard; Benjamin M Friedrich
Reasons for production decline in the diatomite, Belridge oil field: a rock mechanics view
This work summarized research conducted on diatomite cores from the Belridge oil field in Kern County. The study was undertaken to try to explain the rapid decline in oil production in diatomite wells. Characterization of the rock showed that the rock was composed principally of amorphous opaline silica diatoms with only a trace of crystoballite quartz or chert quartz. Physical properties tests showed the diatomite to be of low strength and plastic. Finally, it was established that long-term creep of diatomite into a propped fracture proceeds at a rate of approximately 6 x 10-5 in./day, a phenomenon which may be a primary cause of rapid production declines. The testing program also revealed a matrix stength for the formation of calculated 1325 PSI, a value to consider when depleting the reservoir. This also may help to explain the phase transformation of opal ct at calculated 2000 to 2500 ft depth.
Strickland, F.G.
Majorana Electroformed Copper Mechanical Analysis
The MAJORANA DEMONSTRATOR is a large array of ultra-low background high-purity germanium detectors, enriched in 76Ge, designed to search for zero-neutrino double-beta decay. The DEMONSTRATOR will utilize ultra high purity electroformed copper for a variety of detector components and shielding. A preliminary mechanical evaluation was performed on the Majorana prototype electroformed copper material. Several samples were removed from a variety of positions on the mandrel. Tensile testing, optical metallography, scanning electron microscopy, and hardness testing were conducted to evaluate mechanical response. Analyses carried out on the Majorana prototype copper to this point show consistent mechanical response from a variety of test locations. Evaluation shows the copper meets or exceeds the design specifications.
Overman, Nicole R.; Overman, Cory T.; Kafentzis, Tyler A.; Edwards, Danny J.; Hoppe, Eric W.
Rock Art in the Public Trust: Managing Prehistoric Rock Art on Federal Land
Archaic North America. ? In Handbook of Rock Art Research,Rock Art Analysis. ? In Handbook of Archaeological Methods,Rock Art Analysis,? in Handbook of Archaeological Methods,
Hale, John Patrick
This paper summarizes research conducted on diatomite cores from the Belridge oil field in Kern County, CA. The study was undertaken to explain the rapid decline in oil production in diatomite wells by investigating three of six possible reasons. Characterization of the rock indicated that the rock was composed of principally amorphous opaline silica diatoms with only a trace of crystoballite quartz or chert quartz. Physical properties tests showed the diatomite to be of very low strength and plastic. It was established that longterm creep of diatomite into a propped fracture proceeds at a rate of approximately 1.5 microns/D (1.5 ..mu..m/d), a phenomenon that may contribute to rapid production declines. Also revealed was a matrix strength for the formation of about 1,325 psi (9136 kPa), a critical value to consider when depleting the reservoir. This also may help to explain the phase transformation to Opal CT around 2,000to 2,500-ft (610- to 762-m) depth.
Independent Analysis of Seismicity and Rock fall Scenarios for the Yucca Mountain Repository
Yucca Mountain is located in the somewhat seismically active Basin and Range province. Future seismic activity is identified by the US Nuclear Regulatory Commission and the US National Academy of Sciences as a key scenario for safety assessment of a proposed repository at Yucca Mountain. As part of its on-going program of conducting independent analyses of scientific and technical issues that could be important to the licensing of the Yucca Mountain repository, EPRI has conducted an analysis of the combined scenarios of seismic activity and stability of emplacement drifts with respect to the long-term repository safety. In this paper we present the results of 3D finite element simulations of both static and dynamic loading of a degraded waste package. For the static case, the expected maximum static load is determined by utilizing relationships between cave height and the bulking factor. A static load representing 30 meters of broken rock was simulated using the finite element model. For the dynamic case, block size and velocity data from the most recent Drift Degradation AMR are used. Based on this, a rock block with a volume of 3.11 m{sup 3} and with an impact velocity of 4.81 m/s was simulated using the finite element model. In both cases, the results indicate that the waste package remains intact. (authors)
Apted, M.J. [Monitor Scientific, 3900 S. Wadsworth Blvd., Denver, CO 80235 (United States); Kemeny, J.M. [University of Arizona, Dept. Mining and Geological Engineering, Tucson, AZ 85721 (United States); Martin, C.D. [University of Alberta, Dept. Civil and Environmental Engineering, Edmonton, AB T6G 2W2 (Canada); James, R.J. [Anatech Corp., 5435 Oberlin Dr., San Diego, CA 92121 (United States)
3D Modeling of Coupled Rock Deformation and Thermo-Poro-Mechanical Processes in Fractures
Problems involving coupled thermo-poro-chemo-mechanical processes are of great importance in geothermal and petroleum reservoir systems. In particular, economic power production from enhanced geothermal systems, effective water-flooding of petroleum reservoirs, and stimulation of gas shale reservoirs are significantly influenced by coupled processes. During such procedures, stress state in the reservoir is changed due to variation in pore fluid pressure and temperature. This can cause deformation and failure of weak planes of the formation with creation of new fractures, which impacts reservoir response. Incorporation of geomechanical factor into engineering analyses using fully coupled geomechanics-reservoir flow modeling exhibits computational challenges and numerical difficulties. In this study, we develop and apply efficient numerical models to solve 3D injection/extraction geomechanics problems formulated within the framework of thermo-poro-mechanical theory with reactive flow. The models rely on combining Displacement Discontinuity (DD) Boundary Element Method (BEM) and Finite Element Method (FEM) to solve the governing equations of thermo-poro-mechanical processes involving fracture/reservoir matrix. The integration of BEM and FEM is accomplished through direct and iterative procedures. In each case, the numerical algorithms are tested against a series of analytical solutions. 3D study of fluid injection and extraction into the geothermal reservoir illustrates that thermo-poro-mechanical processes change fracture aperture (fracture conductivity) significantly and influence the fluid flow. Simulations that consider joint stiffness heterogeneity show development of non-uniform flow paths within the crack. Undersaturated fluid injection causes large silica mass dissolution and increases fracture aperture while supersaturated fluid causes mineral precipitation and closes fracture aperture. Results show that for common reservoir and injection conditions, the impact of fully developed thermoelastic effect on fracture aperture tend to be greater compare to that of poroelastic effect. Poroelastic study of hydraulic fracturing demonstrates that large pore pressure increase especially during multiple hydraulic fracture creation causes effective tensile stress at the fracture surface and shear failure around the main fracture. Finally, a hybrid BEFEM model is developed to analyze stress redistribution in the overburden and within the reservoir during fluid injection and production. Numerical results show that fluid injection leads to reservoir dilation and induces vertical deformation, particularly near the injection well. However, fluid withdrawal causes reservoir to compact. The Mandel-Cryer effect is also successfully captured in numerical simulations, i.e., pore pressure increase/decrease is non-monotonic with a short time values that are above/below the background pore pressure.
Rawal, Chakra
Quantitative Financial Analysis of Alternative Energy Efficiency Shareholder Incentive Mechanisms
Analysis of Alternative Energy Efficiency ShareholderAnalysis of Alternative Energy Efficiency Shareholderof alternative shareholder incentive mechanisms for energy
Cappers, Peter
Training and Research on Probabilistic Hydro-Thermo-Mechanical Modeling of Carbon Dioxide Geological Sequestration in Fractured Porous Rocks
Colorado School of Mines conducted research and training in the development and validation of an advanced CO{sub 2} GS (Geological Sequestration) probabilistic simulation and risk assessment model. CO{sub 2} GS simulation and risk assessment is used to develop advanced numerical simulation models of the subsurface to forecast CO2 behavior and transport; optimize site operational practices; ensure site safety; and refine site monitoring, verification, and accounting efforts. As simulation models are refined with new data, the uncertainty surrounding the identified risks decrease, thereby providing more accurate risk assessment. The models considered the full coupling of multiple physical processes (geomechanical and fluid flow) and describe the effects of stochastic hydro-mechanical (H-M) parameters on the modeling of CO{sub 2} flow and transport in fractured porous rocks. Graduate students were involved in the development and validation of the model that can be used to predict the fate, movement, and storage of CO{sub 2} in subsurface formations, and to evaluate the risk of potential leakage to the atmosphere and underground aquifers. The main major contributions from the project include the development of: 1) an improved procedure to rigorously couple the simulations of hydro-thermomechanical (H-M) processes involved in CO{sub 2} GS; 2) models for the hydro-mechanical behavior of fractured porous rocks with random fracture patterns; and 3) probabilistic methods to account for the effects of stochastic fluid flow and geomechanical properties on flow, transport, storage and leakage associated with CO{sub 2} GS. The research project provided the means to educate and train graduate students in the science and technology of CO{sub 2} GS, with a focus on geologic storage. Specifically, the training included the investigation of an advanced CO{sub 2} GS simulation and risk assessment model that can be used to predict the fate, movement, and storage of CO{sub 2} in underground formations, and the evaluation of the risk of potential CO{sub 2} leakage to the atmosphere and underground aquifers.
Gutierrez, Marte
Thermal-chemical-mechanical feedback during fluid-rock interactions: Implications for chemical transport and scales of equilibria in the crust
Our research evaluates the hypothesis that feedback amongst thermal-chemical-mechanical processes operative in fluid-rock systems alters the fluid flow dynamics of the system which, in turn, affects chemical transport and temporal and spatial scales of equilibria, thus impacting the resultant mineral textural development of rocks. Our methods include computational experimentation and detailed analyses of fluid-infiltrated rocks from well-characterized terranes. This work focuses on metamorphic rocks and hydrothermal systems where minerals and their textures are utilized to evaluate pressure (P), temperature (T), and time (t) paths in the evolution of mountain belts and ore deposits, and to interpret tectonic events and the timing of these events. Our work on coupled processes also extends to other areas where subsurface flow and transport in porous media have consequences such as oil and gas movement, geothermal system development, transport of contaminants, nuclear waste disposal, and other systems rich in fluid-rock reactions. Fluid-rock systems are widespread in the geologic record. Correctly deciphering the products resulting from such systems is important to interpreting a number of geologic phenomena. These systems are characterized by complex interactions involving time-dependent, non-linear processes in heterogeneous materials. While many of these interactions have been studied in isolation, they are more appropriately analyzed in the context of a system with feedback. When one process impacts another process, time and space scales as well as the overall outcome of the interaction can be dramatically altered. Our goals to test this hypothesis are: to develop and incorporate algorithms into our 3D heat and mass transport code to allow the effects of feedback to be investigated numerically, to analyze fluid infiltrated rocks from a variety of terranes at differing P-T conditions, to identify subtle features of the infiltration of fluids and/or feedback, and to quantify the importance of feedback in complex fluid-rock systems and its affects on time and space scales and rates of reaction. We have made significant contributions toward understanding feedback and its impacts by numerical experimentation using 3D computational modeling of fluid-rock systems and by chemical and textural analyses of fluid-infiltrated rocks.
Dutrow, Barbara
Rock matrix and fracture analysis of flow in western tight gas sands
Advanced core analysis includes measurements on the matrix properties of the rock. Matrix properties are important even in fractured wells since it is these properties which determine the rate of gas flow into the fractures. Cores are being tested from the fluvial, coastal, and paludal zones of the Mesaverde. At least two cores from each of these zones from all three wells will be analyzed. Properties measured include permeability as a function of confining pressure over the range of 500 to 5000 psi. A minimum of two Klinkenberg permeabilities are being determined from at least five data points. Interpretation includes estimates of pore size from gas slippage. Water adsorption and desorption isotherms will be determined for selected samples with data points being obtained at the following relative humidities: 0, 20, 40, 60, 75, 90, 92, 95 and 98. Porosity measurements from both thin section examination and volumetric measurements are being made. These results will be compared with the porosities of the cored internals determined from logs.
Morrow, N.R.; Brower, K.R.; Ward, J.S.
Workshop on hydrology of crystalline basement rocks
This workshop covered the following subjects: measurements in relatively shallow boreholes; measurement and interpretation of data from deep boreholes; hydrologic properties of crystalline rocks as interpreted by geophysics and field geology; rock mechanics related to hydrology of crystalline rocks; the possible contributions of modeling to the understanding of the hydrology of crystalline rocks; and geochemical interpretations of the hydrology of crystalline rocks. (MHR)
Davis, S.N. (comp.)
Abstract: Natural regeneration on waste rock was investigated at the old Wangaloa coal mine, south-east Otago. A 450-m long waste rock stack had been created 40�50 years ago, and has had little anthropogenic intervention since. The stack is made up of a gradient of three main waste rock types, defined as �silt-rich�, �mixed�, and �quartz-rich�, which reflect different proportions of loess siltstone and quartz gravel conglomerate. Plant species assemblages were quantified in four 5-m 2 quadrats in each waste rock type. Invertebrates were heat extracted from substrate cores (7 cm diameter; depth 5 cm) collected from quadrats over an eight-week period in spring 2003. Ordination analysis showed statistically distinct plant and invertebrate assemblages had arisen on each waste rock type. Revegetation patterns were dominated by native, woody individuals on all waste rock types, particularly manuka (Leptospermum scoparium) and kanuka (Kunzea ericoides). Plant cover on �silt-rich � waste rock was four-fold that on �quartz-rich � waste rock. Total numbers of invertebrates were highest on �quartz-rich� waste rock, but richness greatest on �silt-rich � waste rock. Collembola dominated the fauna but their numbers were proportionally greatest in poorly vegetated areas. Further work is required to explain the absence of plants and invertebrates from local areas of waste rock. ___________________________________________________________________________________________________________________________________
C. G. Rufaut; S. Hammit; D. Craw; S. G. Clearwater
Numerical Modeling of Hydraulic Fracture Propagation Using Thermo-hydro-mechanical Analysis with Brittle Damage Model by Finite Element Method
Better understanding and control of crack growth direction during hydraulic fracturing are essential for enhancing productivity of geothermal and petroleum reservoirs. Structural analysis of fracture propagation and impact on fluid flow is a challenging issue because of the complexity of rock properties and physical aspects of rock failure and fracture growth. Realistic interpretation of the complex interactions between rock deformation, fluid flow, heat transfer, and fracture propagation induced by fluid injection is important for fracture network design. In this work, numerical models are developed to simulate rock failure and hydraulic fracture propagation. The influences of rock deformation, fluid flow, and heat transfer on fracturing processes are studied using a coupled thermo-hydro-mechanical (THM) analysis. The models are used to simulate microscopic and macroscopic fracture behaviors of laboratory-scale uniaxial and triaxial experiments on rock using an elastic/brittle damage model considering a stochastic heterogeneity distribution. The constitutive modeling by the energy release rate-based damage evolution allows characterizing brittle rock failure and strength degradation. This approach is then used to simulate the sequential process of heterogeneous rock failures from the initiation of microcracks to the growth of macrocracks. The hydraulic fracturing path, especially for fractures emanating from inclined wellbores and closed natural fractures, often involves mixed mode fracture propagation. Especially, when the fracture is inclined in a 3D stress field, the propagation cannot be modeled using 2D fracture models. Hence, 2D/3D mixed-modes fracture growth from an initially embedded circular crack is studied using the damage mechanics approach implemented in a finite element method. As a practical problem, hydraulic fracturing stimulation often involves fluid pressure change caused by injected fracturing fluid, fluid leakoff, and fracture propagation with brittle rock behavior and stress heterogeneities. In this dissertation, hydraulic fracture propagation is simulated using a coupled fluid flow/diffusion and rock deformation analysis. Later THM analysis is also carried out. The hydraulic forces in extended fractures are solved using a lubrication equation. Using a new moving-boundary element partition methodology (EPM), fracture propagation through heterogeneous media is predicted simply and efficiently. The method allows coupling fluid flow and rock deformation, and fracture propagation using the lubrication equation to solve for the fluid pressure through newly propagating crack paths. Using the proposed model, the 2D/3D hydraulic fracturing simulations are performed to investigate the role of material and rock heterogeneity. Furthermore, in geothermal and petroleum reservoir design, engineers can take advantage of thermal fracturing that occurs when heat transfers between injected flow and the rock matrix to create reservoir permeability. These thermal stresses are calculated using coupled THM analysis and their influence on crack propagation during reservoir stimulation are investigated using damage mechanics and thermal loading algorithms for newly fractured surfaces.
Min, Kyoung
Mechanical and transport properties of rocks at high temperatures and pressures. Task I. The physical nature of fracturing at depth. Final report
The deformational behavior of granitic rocks is important to a wide variety of national and academic concerns. Both transient and steady state behavior at elevated temperature and pressure, in the presence and absence of excess H2O, have been investigated recently in solid pressure medium equipment and deformation mechanisms and empirical steady state flow laws have been determined. Efforts in the more precise gas and fluid pressure media apparatus have generally been concentrated on low pressure transient creep in order to evaluate effects of stress, temperature, pore pressure and, most recently, strain rate on failure times and static fatigue processes. Additional research is required and the stage is now set for a thorough physical understanding of the evolution from elastic-brittle, through transient (work-hardening)-semibrittle to steady-state-semibrittle to ductile flow of granitic rocks under both dry and wet (saline fluid pore pressure) conditions. 31 refs., 9 figs.
Carter, N.L.
Overview: Hard Rock Penetration
The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.
Dunn, J.C.
Overview - Hard Rock Penetration
The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling Organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.
Dunn, James C.
Technical and cost analysis of rock-melting systems for producing geothermal wells. [GEOWELL
The drilling of wells makes up a large fraction of the costs of geothermal energy-extraction plants, and billions of dollars for wells will be needed before geothermal energy is nationally significant. Technical and economic systems studies are summarized regarding the application of the Subterrene concept, i.e., excavating and penetrating rocks or soils by melting, to the production of deep wells such as may be used for dry hot rock or geopressurized geothermal energy-extraction systems. Technically, it was found that Subterrene features are compatible with those of current rotary drilling practices. In fact, some special features could lead to improved well production techniques. These include the buildup of a glass lining along the borehole wall which provides structural resistance to collapse; close control of hole geometry; the existence of a barrier between the drilling fluids and the formations being penetrated; nonrotation; potentially better bit life; and faster rates of penetration in deep, hard rock. A typical optimum-cost well would be rotary-drilled in the upper regions and then rock-melted to total depth. Indicated cost savings are significant: a 30 percent or 3.9 million dollar (1975 $) reduction from rotary-drilled well costs are estimated for a 10-km depth well with a bottom hole temperature of 673 K. Even for relatively cool normal geothermal gradient conditions, the savings for the 1..pi..-km well are estimated as 23 percent of 2.1 million dollars.
Altseimer, J.H.
Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has cross-flow and counter-current MDCT's consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to simulate the cooling tower performance for the counter-current cooling tower and to conduct a parametric study under different fan speeds and ambient air conditions. The Savannah River National Laboratory (SRNL) developed a computational fluid dynamics (CFD) model and performed the benchmarking analysis against the integral measurement results to accomplish the objective. The model uses three-dimensional steady-state momentum, continuity equations, air-vapor species balance equation, and two-equation turbulence as the basic governing equations. It was assumed that vapor phase is always transported by the continuous air phase with no slip velocity. In this case, water droplet component was considered as discrete phase for the interfacial heat and mass transfer via Lagrangian approach. Thus, the air-vapor mixture model with discrete water droplet phase is used for the analysis. A series of parametric calculations was performed to investigate the impact of wind speeds and ambient conditions on the thermal performance of the cooling tower when fans were operating and when they were turned off. The model was also benchmarked against the literature data and the SRS integral test results for key parameters such as air temperature and humidity at the tower exit and water temperature for given ambient conditions. Detailed results will be published here.
Lee, S; Alfred Garrett, A; James02 Bollinger, J; Larry Koffman, L
Investigations of Near-Field Thermal-Hydrologic-Mechanical-Chemical Models for Radioactive Waste Disposal in Clay/Shale Rock
Clay/shale has been considered as potential host rock for geological disposal of high-level radioactive waste throughout the world, because of its low permeability, low diffusion coefficient, high retention capacity for radionuclides, and capability to self-seal fractures. For example, Callovo-Oxfordian argillites at the Bure site, France (Fouche et al., 2004), Toarcian argillites at the Tournemire site, France (Patriarche et al., 2004), Opalinus Clay at the Mont Terri site, Switzerland (Meier et al., 2000), and Boom clay at the Mol site, Belgium (Barnichon and Volckaert, 2003) have all been under intensive scientific investigation (at both field and laboratory scales) for understanding a variety of rock properties and their relationships to flow and transport processes associated with geological disposal of radioactive waste. Figure 1-1 presents the distribution of clay/shale formations within the USA.
Liu, H.H.; Li, L.; Zheng, L.; Houseworth, J.E.; Rutqvist, J.
Integrated Electro-Thermo-Mechanical Analysis of Spark Plasma ...
The modeling includes novel constitutive concepts of spark plasma sintering and the finite-element analysis with coupled electrical, thermal, and mechanical�...
Environmental analysis of the Fenton Hill Hot Dry Rock Geothermal Test Site
Techniques for the extraction of geothermal energy from hot dry rock within the earth's crust were tested at the first experimental system at Fenton Hill and proved successful. Because new concepts were being tried and new uses of the natural resources were being made, environmental effects were a major concern. Therefore, at all phases of development and operation, the area was monitored for physical, biological, and social factors. The results were significant because after several extended operations, there were no adverse environmental effects, and no detrimental social impacts were detected. Although these results are specific for Fenton Hill, they are applicable to future systems at other locations.
Kaufman, E.L.; Siciliano, C.L.B. (comps.)
Hot rocks
Four kilometers down below the orange earth of Australia�s Cooper Basin lies some of the hottest nonvolcanic rock in the world�rock that the geothermal industry had never seriously considered using to make electricity. But next month Geodynamics, an ...
S. Upson
FAQS Gap Analysis Qualification Card � Mechanical Systems
Energy.gov (U.S. Department of Energy (DOE))
Functional Area Qualification Standard Gap Analysis Qualification Cards outline the differences between the last and latest version of the FAQ Standard.
Rock Joint Surfaces Measurement and Analysis of Aperture Distribution under Different Normal and Shear Loading Using GIS
Geometry of the rock joint is a governing factor for joint mechanical and hydraulic behavior. A new method of evaluating aperture distribution based on measurement of joint surfaces and three dimensional characteristics of each surface is developed. Artificial joint of granite surfaces are measured,processed, analyzed and three dimensional approaches are carried out for surface characterization. Parameters such as asperity's heights, slope angles, and aspects distribution at micro scale,local concentration of elements and their spatial localization at local scale are determined by Geographic Information System (GIS). Changes of aperture distribution at different normal stresses and various shear displacements are visualized and interpreted. Increasing normal load causes negative changes in aperture frequency distribution which indicates high joint matching. However, increasing shear displacement causes a rapid increase in the aperture and positive changes in the aperture frequency distribution which could be ...
Sharifzadeh, Mostafa; Esaki, Tetsuro
A New Natural Gamma Radiation Measurement System for Marine Sediment and Rock Analysis
A new high-efficiency and low-background system for the measurement of natural gamma radioactivity in marine sediment and rock cores retrieved from beneath the seabed was designed, built, and installed on the JOIDES Resolution research vessel. The system includes eight large NaI(Tl) detectors that measure adjacent intervals of the core simultaneously, maximizing counting times and minimizing statistical error for the limited measurement times available during drilling expeditions. Effect to background ratio is maximized with passive lead shielding, including both ordinary and low-activity lead. Large-area plastic scintillator active shielding filters background associated with the high-energy part of cosmic radiation. The new system has at least an order of magnitude higher statistical reliability and significantly enhances data quality compared to other offshore natural gamma radiation (NGR) systems designed to measure geological core samples. Reliable correlations and interpretations of cored intervals are ...
Vasiliev, M A; Chubarian, G; Olsen, R; Bennight, C; Cobine, T; Fackler, D; Hastedt, M; Houpt, D; Mateo, Z; Vasilieva, Y B
Structural analysis of porous rock reservoirs subjected to conditions of compressed air energy storage
Investigations are described which were performed to assess the structural behavior of porous rock compressed air energy storage (CAES) reservoirs subjected to loading conditions of temperature and pressure felt to be typical of such an operation. Analyses performed addressed not only the nominal or mean reservoir response but also the cyclic response due to charge/discharge operation. The analyses were carried out by assuming various geometrical and material related parameters of a generic site. The objective of this study was to determine the gross response of a generic porous reservoir. The site geometry for this study assumed a cylindrical model 122 m in dia and 57 m high including thicknesses for the cap, porous, and base rock formations. The central portion of the porous zone was assumed to be at a depth of 518 m and at an initial temperature of 20/sup 0/C. Cyclic loading conditions of compressed air consisted of pressure values in the range of 4.5 to 5.2 MPa and temperature values between 143 and 204/sup 0/C.Various modes of structural behavior were studied. These response modes were analyzed using loading conditions of temperature and pressure (in the porous zone) corresponding to various operational states during the first year of simulated site operation. The results of the structural analyses performed indicate that the most severely stressed region will likely be in the wellbore vicinity and hence highly dependent on the length of and placement technique utilized in the well production length. Analyses to address this specific areas are currently being pursued.
Friley, J.R.
We analyzed a data set of thermally induced changes in fractured rock permeability during a four-year heating (up to 200 C) and subsequent four-year cooling of a large volume, partially saturated and highly fractured volcanic tuff at the Yucca Mountain Drift Scale Test, in Nevada, USA. Permeability estimates were derived from about 700 pneumatic (air-injection) tests, taken periodically at 44 packed-off borehole intervals during the heating and cooling cycle from November 1997 through November 2005. We analyzed air-permeability data by numerical modeling of thermally induced stress and moisture movements and their impact on air permeability within the highly fractured rock. Our analysis shows that changes in air permeability during the initial four-year heating period, which were limited to about one order of magnitude, were caused by the combined effects of thermal-mechanically-induced stress on fracture aperture and thermal-hydrologically-induced changes in fracture moisture content. At the end of the subsequent four-year cooling period, air-permeability decreases (to as low as 0.2 of initial) and increases (to as high as 1.8 of initial) were observed. By comparison to the calculated thermo-hydro-elastic model results, we identified these remaining increases or decreases in air permeability as irreversible changes in intrinsic fracture permeability, consistent with either inelastic fracture shear dilation (where permeability increased) or inelastic fracture surface asperity shortening (where permeability decreased). In this paper, we discuss the possibility that such fracture asperity shortening and associated decrease in fracture permeability might be enhanced by dissolution of highly stressed surface asperities over years of elevated stress and temperature.
Rutqvist, J.; Freifeld, B.; Min, K.-B.; Elsworth, D.; Tsang, Y.
In Situ NMR Analysis of Fluids Contained in Sedimentary Rock Thomas M. de Swiet,* Marco Tomaselli,* Martin D. Hurlimann, and Alexander Pines*
In Situ NMR Analysis of Fluids Contained in Sedimentary Rock Thomas M. de Swiet,* Marco Tomaselli of pore fluids may be obtained in situ by magic angle spinning (MAS) nuclear magnetic resonance (NMR), which is normally used for solid samples. 1 H MASNMR spectra of water and crude oil in Berea sandstone
Pines, Alexander
Crustal Rock Fracture Mechanics for Design and Control of Artificial Subsurface Cracks in Geothermal Energy Extraction Engineering ({Gamma}-Project)
Recently a significant role of artificial and/or natural cracks in the geothermal reservoir has been demonstrated in the literatures (Abe, H., et al., 1983, Nielson, D.L. and Hullen, J.B., 1983), where the cracks behave as fluid paths and/or heat exchanging surfaces. Until now, however, there are several problems such as a design procedure of hydraulic fracturing, and a quantitative estimate of fluid and heat transfer for reservoir design. In order to develop a design methodology of geothermal reservoir cracks, a special distinguished research project, named as ''{Lambda}-Project'', started at Tohoku University (5 years project, 1983-1988). In this project a basic fracture mechanics model of geothermal reservoir cracks is being demonstrated and its validation is being discussed both theoretically and experimentally. This paper descibes an outline of ''{Lambda}-Project''.
Abe, Hiroyuki; Takahashi, Hideaki
Rock matrix and fracture analysis of flow in western tight gas sands: 1986 annual report
This report presents progress for the second year of a five-year project concerned with the pore structure and flow properties of low permeability gas sands. The main objective of work during the first year was to carry out advanced core analysis on cores recovered from the Multi-Well Field Experiment. In Phase 2, the properties of both fractured and non-fractured samples (hereafter referred to as matrix) have been studied. Special attention was given to the combined effect of overburden pressure and water saturation on gas flow. 11 refs., 18 figs., 4 tabs.
Morrow, N.R.; Buckley, J.S.; Cather, S.M.; Brower, K.R.; Dandge, V.; Graham, M.; Gonzales, B.
Economic predictions for heat mining : a review and analysis of hot dry rock (HDR) geothermal energy technology
The main objectives of this study were first, to review and analyze several economic assessments of Hot Dry Rock (HDR) geothermal energy systems, and second, to reformulate an economic model for HDR with revised cost components.
Tester, Jefferson W.
Proceedings of hot dry rock geothermal workshop
Abstracts of 38 papers are included on the following subjects: rock mechanics, part 1: hydraulic fracturing; fracture imaging and borehole surveying; fluid flow-pressure analyses; rock mechanics, part 2: hydraulic fracturing and thermal cracking; geochemistry; heat extraction modeling; and economics and energy conversion. (MHR)
Elsner, D.B. (comp.)
Rock Density | Open Energy Information
form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit with form History Facebook icon Twitter icon » Rock Density Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Rock Density Details Activities (2) Areas (2) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Density of different lithologic units. Stratigraphic/Structural: Hydrological: Thermal: Cost Information Low-End Estimate (USD): 10.001,000 centUSD 0.01 kUSD 1.0e-5 MUSD 1.0e-8 TUSD / sample
Economic Predictions for Heat Mining: A Review and Analysis of Hot Dry Rock (HDR) Geothermal Energy Technology
The main objectives of this study were first, to review and analyze several economic assessments of Hot Dry Rock (HDR) geothermal energy systems, and second, to reformulate an economic model for HDR with revised cost components. The economic models reviewed include the following studies sponsored by Electric Power Research Institute (EPRI)-Cummings and Morris (1979), Los Alamos National Laboratory (LANL)-Murphy, et al. (1982), United Kingdom (UK)-Shock (1986), Japan-Hori, et al. (1986), Meridian-Entingh (1987) and Bechtel (1988). A general evaluation of the technical feasibility of HDR technology components was also conducted in view of their importance in establishing drilling and reservoir performance parameters required for any economic assessment. In this review, only economic projections for base load electricity produced from HDR systems were considered. Bases of 1989 collars ($) were selected to normalize costs. Following the evaluation of drilling and reservoir performance, power plant choices and cost estimates are discussed in section 6 of the report. In Section 7, the six economics studies cited above are reviewed and compared in terms of their key resource, reservoir and plant performance, and cost assumptions. Based on these comparisons, the report estimates parameters for three composite cases. Important parameters include: (1) resource quality-average geothermal gradient (C/km) and well depth, (2) reservoir performance-effective productivity, flow impedance, and lifetime (thermal drawdown rate), (3) cost components-drilling, reservoir formation, and power plant costs and (4) economic factors-discount and interest rates, taxes, etc. In Section 8, composite case conditions were used to reassess economic projections for HDR-produced electricity. In Section 9, a generalized economic model for HDR-produced electricity is presented to show the effects of resource grade, reservoir performance parameters, and other important factors on projected costs. A sensitivity and uncertainty analysis using this model is given in Section 10. Section 11 treats a modification of the economic model for predicting costs for direct, non-electric applications. HDR economic projections for the U.S. are broken down by region in Section 12. In Section 13, the report provides recommendations for continued research and development to reduce technical and economic uncertainties relevant to the commercialization of HDR. [DJE-2005
Tester, Jefferson W.; Herzog, Howard J.
Mechanical and transport properties of rocks at high temperatures and pressures. Task II. Fracture permeability of crystalline rocks as a function of temperature, pressure, and hydrothermal alteration. Final report
Pore-fluid chemical interactions on both short and long time scales can significantly change the permeability of a rock. Measurement of the permeability variations requires adaption and modification on standard measurement systems, with special attention given to pore-fluid flow rates and metal corrosion of system components. In this report, system requirements and capabilities are reviewed, analyzed, and recommendations made. Special attention is given to the choice of corrosion resistant metals, fluid-flow systems, back-pressure systems, jacketing materials, and flow-rate measurement. On the basis of this study, an economical, highly flexible, permeability system was designed and built. The system allows measurement of permeability over the darcy to nanodarcy range, using geologically meaningful, chemically reactive, pore fluids under constant volume flow rates as small as 0.2 ml/day at temperatures in excess of 300C, fluid pressures to 20 MPa, and confining pressures to 100 MPa. 7 refs., 3 figs., 1 tab.
Johnson, B.
Rising energy prices and climate change are central issues in the debate about our nation's energy policy. Many are demanding increased energy efficiency as a way to help reduce greenhouse gas emissions and lower the total cost of electricity and energy services for consumers and businesses. Yet, as the National Action Plan on Energy Efficiency (NAPEE) pointed out, many utilities continue to shy away from seriously expanding their energy efficiency program offerings because they claim there is insufficient profit-motivation, or even a financial disincentive, when compared to supply-side investments. With the recent introduction of Duke Energy's Save-a-Watt incentive mechanism and ongoing discussions about decoupling, regulators and policymakers are now faced with an expanded and diverse landscape of financial incentive mechanisms, Determining the 'right' way forward to promote deep and sustainable demand side resource programs is challenging. Due to the renaissance that energy efficiency is currently experiencing, many want to better understand the tradeoffs in stakeholder benefits between these alternative incentive structures before aggressively embarking on a path for which course corrections can be time-consuming and costly. Using a prototypical Southwest utility and a publicly available financial model, we show how various stakeholders (e.g. shareholders, ratepayers, etc.) are affected by these different types of shareholder incentive mechanisms under varying assumptions about program portfolios. This quantitative analysis compares the financial consequences associated with a wide range of alternative incentive structures. The results will help regulators and policymakers better understand the financial implications of DSR program incentive regulation.
Cappers, Peter; Goldman, Charles; Chait, Michele; Edgar, George; Schlegel, Jeff; Shirley, Wayne
DOE Hydrogen Analysis Repository: Fuel Cell Water Transport Mechanism
NLE Websites -- All DOE Office Websites (Extended Search)
Water Transport Mechanism Project Summary Full Title: Neutron Imaging Study of the Water Transport Mechanism in a Working Fuel Cell Project ID: 183 Principal Investigator: Muhammad...
Single Variable and Multivariate Analysis of Remote Laser-Induced Breakdown Spectra for Prediction of Rb, Sr, Cr, Ba, and V in Igneous Rocks
Laser-induced breakdown spectroscopy (LIBS) will be employed by the ChemCam instrument on the Mars Science Laboratory rover Curiosity to obtain UV, VIS, and VNIR atomic emission spectra of surface rocks and soils. LIBS quantitative analysis is complicated by chemical matrix effects related to abundances of neutral and ionized species in the resultant plasma, collisional interactions within plasma, laser-to-sample coupling efficiency, and self-absorption. Atmospheric composition and pressure also influence the intensity of LIBS plasma. These chemical matrix effects influence the ratio of intensity or area of a given emission line to the abundance of the element producing that line. To compensate for these complications, multivariate techniques, specifically partial least-squares regression (PLS), have been utilized to predict major element compositions (>1 wt.% oxide) of rocks, PLS methods regress one or multiple response variables (elemental concentrations) against multiple explanatory variables (intensity at each pixel of the spectrometers). Because PLS utilizes all available explanatory variable and eliminates multicollinearity, it generally performs better than univariate methods for prediction of major elements. However, peaks arising from emissions from trace elements may be masked by peaks of higher intensities from major elements. Thus in PLS regression, wherein a correlation coefficient is determined for each elemental concentration at each spectrometer pixel, trace elements may show high correlation with more intense lines resulting from optical emissions of other elements. This could result in error in predictions of trace element concentrations. Here, results of simple linear regression (SLR) and multivariate PLS-2 regression for determination of trace Rb, Sr, Cr, Ba, and V in igneous rock samples are compared. This study focuses on comparisons using only line intensities rather than peak areas to highlight differences between SLR and PLS.
Clegg, Samuel M [Los Alamos National Laboratory; Wiens, Roger C. [Los Alamos National Laboratory; Speicher, Elly A [MT HOLYOKE COLLEGE; Dyar, Melinda D [MT HOLYOKE COLLEGE; Carmosino, Marco L [MT HOLYOKE COLLEGE
Majorana Demonstrator Bolted Joint Mechanical and Thermal Analysis
The MAJORANA DEMONSTRATOR is designed to probe for neutrinoless double-beta decay, an extremely rare process with a half-life in the order of 1026 years. The experiment uses an ultra-low background, high-purity germanium detector array. The germanium crystals are both the source and the detector in this experiment. Operating these crystals as ionizing radiation detectors requires having them under cryogenic conditions (below 90 K). A liquid nitrogen thermosyphon is used to extract the heat from the detectors. The detector channels are arranged in strings and thermally coupled to the thermosyphon through a cold plate. The cold plate is joined to the thermosyphon by a bolted joint. This circular plate is housed inside the cryostat can. This document provides a detailed study of the bolted joint that connects the cold plate and the thermosyphon. An analysis of the mechanical and thermal properties of this bolted joint is presented. The force applied to the joint is derived from the torque applied to each one of the six bolts that form the joint. The thermal conductivity of the joint is measured as a function of applied force. The required heat conductivity for a successful experiment is the combination of the thermal conductivity of the detector string and this joint. The thermal behavior of the joint is experimentally implemented and analyzed in this study.
Aguayo Navarrete, Estanislao; Reid, Douglas J.; Fast, James E.
CRC handbook of physical properties of rocks. Volume III
This book presents topics on: Density of rocks and minerals, includes histograms of density ranges; elastic constants of minerals, elastic moduli, thermal properties; inelastic properties, strength and rheology for rocks and minerals, rock mechanics and friction, and stress-strain relations; radioactivity, decay constants and heat production of isotope systems in geology; seismic attenuation, in rocks, minerals, and the earth, with application to oil exploration and terrestrial studies; and index.
Carmichael, R.S.
Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has a MDCT consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to conduct a parametric study for cooling tower performance under different fan speeds and ambient air conditions. The Savannah River National Laboratory (SRNL) developed a computational fluid dynamics (CFD) model to achieve the objective. The model uses three-dimensional steady-state momentum, continuity equations, air-vapor species balance equation, and two-equation turbulence as the basic governing equations. It was assumed that vapor phase is always transported by the continuous air phase with no slip velocity. In this case, water droplet component was considered as discrete phase for the interfacial heat and mass transfer via Lagrangian approach. Thus, the air-vapor mixture model with discrete water droplet phase is used for the analysis. A series of the modeling calculations was performed to investigate the impact of ambient and operating conditions on the thermal performance of the cooling tower when fans were operating and when they were turned off. The model was benchmarked against the literature data and the SRS test results for key parameters such as air temperature and humidity at the tower exit and water temperature for given ambient conditions. Detailed results will be presented here.
Solid Mechanics/Finite-Element Analysis Software/Codes - TMS
CalculiX - A Free Software Three-Dimensional Structural Finite Element Program G. Dhondt and K. Wittig. Open Source (GPL) 3-D Finite Element Mechanics�...
Characterization of porosity in support of mechanical property analysis
Previous laboratory investigations of tuff have shown that porosity has a dominant, general effect on mechanical properties. As a result, it is very important for the interpretation of mechanical property data that porosity is measured on each sample tested. Porosity alone, however, does not address all of the issues important to mechanical behavior. Variability in size and distribution of pore space produces significantly different mechanical properties. A nondestructive technique for characterizing the internal structure of the sample prior to testing is being developed and the results are being analyzed. The information obtained from this technique can help in both qualitative and quantitative interpretation of test results.
Price, R.H. [Sandia National Labs., Albuquerque, NM (United States); Martin, R.J. III; Boyd, P.J. [New England Research, Inc., White River Junction, VT (United States)
Hopf Bifurcation Analysis for a Mechanical Centrifugal Flywheel Governor System
The complex dynamic behavior of the mechanical centrifugal flywheel governor system is studied. The dynamical equation of the system is established using Lagrangian and Newton�s second law. The bifurcation behavior and stability of the mechanical ... Keywords: centrifugal governor, Lyapunov exponents, chaos, chaos synchronization, Poincar� map
Jian-Gang Zhang; Jian-Ning Yu; Yan-Dong Chu; Xian-Feng Li
2008 Rock Deformation GRC - Conference August 3-8, 2008
The GRC on Rock Deformation highlights the latest research in brittle and ductile rock mechanics from experimental, field and theoretical perspectives. The conference promotes a multi-disciplinary forum for assessing our understanding of rock strength and related physical properties in the Earth. The theme for the 2008 conference is 'Real-time Rheology'. Using ever-improving geophysical techniques, our ability to constrain the rheological behavior during earthquakes and post-seismic creep has improved significantly. Such data are used to investigate the frictional behavior of faults, processes responsible for strain localization, the viscosity of the lower crust, and viscous coupling between the crust and mantle. Seismological data also provide information on the rheology of the lower crust and mantle through analysis of seismic attenuation and anisotropy. Geologists are improving our understanding of rheology by combining novel analyses of microstructures in naturally deformed rocks with petrologic data. This conference will bring together experts and students in these research areas with experimentalists and theoreticians studying the same processes. We will discuss and assess where agreement exists on rheological constraints derived at different length/time scales using different techniques - and where new insight is required. To encompass the elements of these topics, speakers and discussion leaders with backgrounds in geodesy, experimental rock deformation, structural geology, earthquake seismology, geodynamics, glaciology, materials science, and mineral physics will be invited to the conference. Thematic sessions will be organized on the dynamics of earthquake rupture, the rheology of the lower crust and coupling with the upper mantle, the measurement and interpretation of seismic attenuation and anisotropy, the dynamics of ice sheets and the coupling of reactive porous flow and brittle deformation for understanding geothermal and chemical properties of the shallow crust that are important for developing ideas in CO2 sequestration, geothermal and petrochemical research and the mechanics of shallow faults.
James G. Hirth
�Electrochemical Shock� of Intercalation Electrodes: A Fracture Mechanics Analysis
Fracture of electrode particles due to diffusion-induced stress has been implicated as a possible mechanism for capacity fade and impedance growth in lithium-ion batteries. In brittle materials, including many lithium ...
Chiang, Yet-Ming
Shotgun cartridge rock breaker
DOE Patents (OSTI)
A rock breaker uses shotgun cartridges or other firearm ammunition as the explosive charge at the bottom of a drilled borehole. The breaker includes a heavy steel rod or bar, a gun with a firing chamber for the ammunition which screws onto the rod, a long firing pin running through a central passage in the rod, and a firing trigger mechanism at the external end of the bar which strikes the firing pin to fire the cartridge within the borehole. A tubular sleeve surround the main body of the rod and includes slits the end to allow it to expand. The rod has a conical taper at the internal end against which the end of the sleeve expands when the sleeve is forced along the rod toward the taper by a nut threaded onto the external end of the rod. As the sleeve end expands, it pushes against the borehole and holds the explosive gasses within, and also prevents the breaker from flying out of the borehole. The trigger mechanism includes a hammer with a slot and a hole for accepting a drawbar or drawpin which, when pulled by a long cord, allows the cartridge to be fired from a remote location.
Ruzzi, Peter L. (Eagan, NM); Morrell, Roger J. (Bloomington, MN)
DIMENSIONAL MODELING OF LASER SPALLATION DRILLING OF ROCKS DIMENSIONAL MODELING OF LASER SPALLATION DRILLING OF ROCKS P532 Zhiyue Xu, Yuichiro Yamashita 1 , and Claude B. Reed Argonne National Laboratory, Argonne, IL 60439, USA 1 Now with Kyushu University, Japan Abstract High power lasers can weaken, spall, melt and vaporize natural earth materials with thermal spallation being the most energy efficient rock removal mechanism. Laser rock spallation is a very complex phenomenon that depends on many factors. Computer numerical modeling would provides great tool to understand the fundamental of this complex phenomenon, which is crucial to the success of its applications. Complexity of modeling laser rock spallation is due to: 1) rock is a porous media, to which traditional theories of heat transfer and rock mechanics can not be directly
Analysis on Wear Mechanism of Refractories Used in Hot Air ...
By analysis, the service life of hot wind stoves can be enhanced by the .... Production of Fe-Based Alloys by Metallothermic Reduction of Mill Scales from�...
A Study of Hydraulic Fracturing Initiation in Transversely Isotropic Rocks
Hydraulic fracturing of transverse isotropic reservoirs is of major interest for reservoir stimulation and in-situ stress estimation. Rock fabric anisotropy not only causes in-situ stress anisotropy, but also affects fracture initiation from the wellbore. In this study a semi-analytical method is used to investigate these effects with particular reference to shale stimulation. Using simplifying assumptions, equations are derived for stress distribution around the wellbore's walls. The model is then used to study the fracture initiation pressure variations with anisotropy. A sensitivity analysis is carried out on the impact of Young's modulus and Poisson's ration, on the fracture initiation pressure. The results are useful in designing hydraulic fractures and also can be used to develop information about in-situ rock properties using failure pressure values observed in the field. Finally, mechanical and permeability anisotropy are measured using Pulse Permeameter and triaxial tests on Pierre shale.
Serajian, Vahid
District, Teller County, Colorado," U.S. Geol. Survey Bull.Jamestown District, Colorado," Econ. Geol. , v. 68, pp 1247-Rocks at Powderhorn, Colorado; Economic Geology, Vol. 60,
Murphy, M.
Session: Hard Rock Penetration
This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Hard Rock Penetration - Summary'' by George P. Tennyson, Jr.; ''Overview - Hard Rock Penetration'' by James C. Dunn; ''An Overview of Acoustic Telemetry'' by Douglas S. Drumheller; ''Lost Circulation Technology Development Status'' by David A. Glowka; ''Downhole Memory-Logging Tools'' by Peter Lysne.
Tennyson, George P. Jr.; Dunn, James C.; Drumheller, Douglas S.; Glowka, David A.; Lysne, Peter
Transient Thermal, Hydraulic, and Mechanical Analysis of a Counter Flow Offset Strip Fin Intermediate Heat Exchanger using an Effective Porous Media Approach
Transient Thermal, Hydraulic, and Mechanical Analysis of a2009 Transient Thermal, Hydraulic, and Mechanical AnalysisAbstract Transient Thermal, Hydraulic, and Mechanical Stress
Urquiza, Eugenio
Evaluation of Five Sedimentary Rocks Other Than Salt for Geologic Repository Siting Purposes
The US Department of Energy (DOE), in order to increase the diversity of rock types under consideration by the geologic disposal program, initiated the Sedimary ROck Program (SERP), whose immediate objectiv eis to evaluate five types of secimdnary rock - sandstone, chalk, carbonate rocks (limestone and dolostone), anhydrock, and shale - to determine the potential for siting a geologic repository. The evaluation of these five rock types, together with the ongoing salt studies, effectively results in the consideration of all types of relatively impermeable sedimentary rock for repository purposes. The results of this evaluation are expressed in terms of a ranking of the five rock types with respect to their potential to serve as a geologic repository host rock. This comparative evaluation was conducted on a non-site-specific basis, by use of generic information together with rock evaluation criteria (RECs) derived from the DOE siting guidelines for geologic repositories (CFR 1984). An information base relevant to rock evaluation using these RECs was developed in hydrology, geochemistry, rock characteristics (rock occurrences, thermal response, rock mechanics), natural resources, and rock dissolution. Evaluation against postclosure and preclosure RECs yielded a ranking of the five subject rocks with respect to their potential as repository host rocks. Shale was determined to be the most preferred of the five rock types, with sandstone a distant second, the carbonate rocks and anhydrock a more distant third, and chalk a relatively close fourth.
Croff, A.G.; Lomenick, T.F.; Lowrie, R.S.; Stow, S.H.
Rock properties in support of geothermal resource development
Geothermal rock mechanics needs have been defined and subsequently a test system was designed and built for providing appropriate material properties. The development areas identified as requiring rock mechanics were stimulation, reservoir engineering, subsidence prediction, surface exploration and subsurface evaluation, and drilling. The resulting test system provides mechanical, electrical, thermal and physical properties on 2 and 4 inch diameter cores at confining pressures and pore fluid pressures to 200 MPa (30,000 psi) and temperatures to 535/sup 0/C (1000/sup 0/F). The test system development was continued and site specific rock mechanics requirements were identified. (MHR)
Butters, S.W.
Rock-ravintolatoiminta : el�v�� rock-musiikkia ravintolaymp�rist�ss�; Rock venue activity : live rock music in the restaurant setting.
??Ty�n tavoitteena oli tutkia rock-ravintolatoimintaa ja el�v�� rock-musiikkia ravintolaymp�rist�ss� ravintolan, artistin ja asiakkaan n�k�kulmasta. Tutkimuksessa pyrittiin selvitt�m��n rock-ravintolayritt�misen toimintatapoja ja kartoittamaan alan t�m�n hetkist� tilaa.� (more)
V�yli�, Jari
Structure-Function Analysis of Edible FatsChapter 5 Rheology and Mechanical Properties of Fats
Structure-Function Analysis of Edible Fats Chapter 5 Rheology and Mechanical Properties of Fats Methods and Analyses eChapters Food Science & Technology Health - Nutrition - Biochemistry Processing Methods - Analyses Books AOCS Press
Mechanical behavior analysis of CDIO production-blood vessel robot in curved blood vessel
In order to analyze mechanical behavior of blood vessel robot (student's CDIO production) in curved blood, and provide the data for outline design of robot, the flow field out side of robot is numerical simulated. The results show that the vessel shape ... Keywords: blood vessel robot, curved blood vessel, mechanical behavior analysis, numerical simulation
Fan Jiang; Chunliang Zhang; Yijun Wang
Analysis of transport mechanisms in dense fuel droplet sprays
This report deals with numerical analyses of fluid mechanics, heat transfer, mass transfer and particle dynamics of interacting spheres and vaporizing droplets in a linear array or on a 1-D trajectory. Available finite element software has been modified and extended to solve several case studies including closely spaced monodisperse spheres with or without blowing; closely spaced vaporizing fuel droplets; and dynamically interacting vaporizing fuel droplets on a 1-D trajectory. Axisymmetric laminar flow has been assumed for three statically or dynamically interacting spherical solids and vaporizing droplets. Emphasis in this work is evaluating the effects of key system parameters, such as free stream Reynolds number, interparticle spacings, liquid/gas-phase viscosity ratio and variable fluid properties, on interfacial transfer processes and on the particle Nusselt number, vaporization rate and drag coefficient. Computer-generated correlations between integral quantities and system parameters were postulated for blowing spheres and vaporizing droplets. In addition to initial Reynolds number and droplet spacings, variable fluid properties, liquid-phase heating and internal droplet circulation have strong effect on the dynamic behavior of multi-droplet systems. While the lead droplet is most significantly affected by all key parameters, the second and third droplet causes distinct interaction effects which are largely dependent on initial droplet spacings. Applications include spherical-structure/fluid-flow interactions, as well as interacting vaporizing droplets in different sprays related to propulsion systems, irrigation, spray coating, etc. Focusing on fuel droplet sprays, results of the dynamic multi-droplet study can assist in better atomizers and combustion chamber designs which may lead to improved combustion efficiencies, smaller/lighter systems, and reduced pollutant emissions.
Kleinstreuer, C.
Oldest Rock on Earth
Canada." and "Some of the oldest surface rock can be found in the Canadian Shield, Australia, Africa and in other more specific places around the world. The ages of...
Analysis Of The Mechanics Of The Ouray, CO Landslide
Mountain areas are prime locations for mass movement activity, as a result of their steep slopes and large amount of local relief. As a rapid mass movement phenomena, landslides are responsible for a considerable numbers of deaths around the world each year. Thus, mitigation plans, such as the �Multi-Hazard Mitigation Plan� published by the County of Ouray, CO, have been developed to identify the spatial and temporal characteristic of potential hazards to minimize impact on humans and real property. The Ouray area has numerous landslides that have been mapped, and a large-sized landslide in this region of the San Juan Mountains is locally referred to as the Amphitheater Landslide. Although the area has been mapped as a landslide, the exact size, extent, and cause of the landslide have not been determined because the complex geological history of the region masks much of the landslide. Identification of the landslide extent and the cause are fundamental to establishing potential risks associated with this landslide. The town of Ouray, which is situated on the floor of a glaciated valley down slope from the scarp of the landslide is situated aside the toe of the landslide. The landslide was mapped using high-resolution, color aerial photography and geomorphic mapping. The landslide is 81,834,372 ft2, composed of San Juan tuff mixed with glacial debris and underlain by the Molas Formation (i.e., weak shale beds). Preliminary examination suggested that the exposed Molas shale experienced strain and saturation during the last interglacial period resulting in decreased shear strength. The valley slopes are draped with moraines, which were emplaced in contact with the glaciers, (i.e., ice-contact), which resulted in slopes that exceeded the angle of repose for the material. As the climate warmed and the glaciers melted, the support that was provided by the ice contact melted and the resulting slopes are today in disequilibrium and prone to failure. This study provides an assessment of the mechanics of movement of the Amphitheater landslide, which can be used to help minimize similar potential hazards.
Reed, John Christopher
Soil mechanics and analysis of soils overlying cavitose bedrock
The stability of the residual soils existing at the West Chestnut Ridge Site, Oak Ridge Reservation, Tennessee, was evaluated. The weathered bedrock below this residual soil contains numerous solution cavities, and several karst features were identified. The West Chestnut Ridge site was evaluated with respect to deformation and collapse of the residual soil into the bedrock cavities. A finite element analysis investigated the effects of bedrock cavity radius, thickness of soil overburden, and surface surcharge upon the deformational and stability characteristics of the residual soil. The results indicate that for small cavity radii, the thickness of the soil cover has little effect on the zone of yielded soil. For large cavity radii, a smaller zone of distressed soil occurs under thick soil cover than under thin soil cover. Dimensionless curves are presented to enable the prediction of the vertical extent of the zone of yielded soil for a range of site geometries. Although the thick soil deposits (100 feet or greater) typically found on the ridges result in high stresses adjacent to the cavity, the area of the distressed or yielded soil is small and unlikely to extend to the surface. In addition, the surface deformation or subsidence is expected to be minimal. Thus, the siting of waste facilities on the ridges where the overburden is maximum would tend to reduce the effects of deformation into the cavities. 29 refs., 37 figs., 7 tabs.
Drumm, E.C.
Analysis of a Third-Generation Princeton Tri-leaflet Mechanical Heart Valve
Analysis of a Third-Generation Princeton Tri-leaflet Mechanical Heart Valve Michael Hsu Advisor heart valve · Static analysis of leaflet under uniform pressure of 10 MPa Summer Objectives · Find Heart valve disease · Over 5 million affected · Over 225,000 valve- replacement surgeries performed
Petta, Jason
Rock Harbor UNITED STATES
Passage Conglomerate Bay Five Finger Bay Lane Cove Stockly Bay Lake Ojibway Siskiwit River Creek Little River Washington Moskey M cCargoe Cove Robinson Bay Amygdaloid Channel Pickerel Cove Chippewa Harbor Crystal Cove Belle Isle Canoe Rocks Caribou Island Saginaw Point Tookers Island The Palisades Raspberry
Modeling the cracking process of rocks from continuity to discontinuity using a cellular automaton
A rock discontinuous cellular automaton (RDCA) was developed for modeling rock fracturing processes from continuous to discontinuous deformation under mechanical loading. RDCA is an integration of the following basic concepts: (1) representation of heterogeneity ... Keywords: Cracking process, Discontinuity, Elasto-plastic cellular automaton, Level set, Partition of unity, Rock discontinuous cellular automaton
Peng-Zhi Pan; Fei Yan; Xia-Ting Feng
International Journal of Mechanical Sciences 48 (2006) 13141322 Design, manufacture, and analysis of metal foam
heating has been used extensively to convert the electrical energy into thermal energy. An analytic heat the electrical energy to thermal energy. The resistance to electrical current in a heating element generates heatInternational Journal of Mechanical Sciences 48 (2006) 13141322 Design, manufacture, and analysis
Shih, Albert J.
Fusion Engineering and Design 81 (2006) 16391645 Thermo-mechanical analysis of a micro-engineered
Fusion Engineering and Design 81 (2006) 16391645 Thermo-mechanical analysis of a micro laser (HAPL) program goal is to develop a laser inertial fusion reactor using a solid first wall (FW). The FW of the inertial fusion energy (IFE) chamber is exposed to high energy photon, particle
Ghoniem, Nasr M.
The Landscape of Klamath Basin Rock Art
the Lines: Ethnographic Sources and Rock Art Interpretationwhen applying these sources toward rock art interpretation.information source for developing rock art interpretations.
David, Robert James
Thermal And Mechanical Analysis of High-power Light-emitting Diodes with Ceramic Packages
In this paper we present the thermal and mechanical analysis of high-power light-emitting diodes (LEDs) with ceramic packages. Transient thermal measurements and thermo-mechanical simulation were performed to study the thermal and mechanical characteristics of ceramic packages. Thermal resistance from the junction to the ambient was decreased from 76.1 oC/W to 45.3 oC/W by replacing plastic mould to ceramic mould for LED packages. Higher level of thermo-mechanical stresses in the chip were found for LEDs with ceramic packages despite of less mismatching coefficients of thermal expansion comparing with plastic packages. The results suggest that the thermal performance of LEDs can be improved by using ceramic packages, but the mounting process of the high power LEDs with ceramic packages is critically important and should be in charge of delaminating interface layers in the packages.
J. Hu; L. Yang; M. -W. Shin
Microwave assisted hard rock cutting
An apparatus for the sequential fracturing and cutting of subsurface volume of hard rock (102) in the strata (101) of a mining environment (100) by subjecting the volume of rock to a beam (25) of microwave energy to fracture the subsurface volume of rock by differential expansion; and , then bringing the cutting edge (52) of a piece of conventional mining machinery (50) into contact with the fractured rock (102).
Lindroth, David P. (Apple Valley, MN); Morrell, Roger J. (Bloomington, MN); Blair, James R. (Inver Grove Heights, MN)
Session: Hot Dry Rock
This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of four presentations: ''Hot Dry Rock - Summary'' by George P. Tennyson, Jr.; ''HDR Opportunities and Challenges Beyond the Long Term Flow Test'' by David V. Duchane; ''Start-Up Operations at the Fenton Hill HDR Pilot Plant'' by Raymond F. Ponden; and ''Update on the Long-Term Flow Testing Program'' by Donald W. Brown.
Tennyson, George P. Jr.; Duchane, David V.; Ponden, Raymond F.; Brown, Donald W.
Definition: Rock Density | Open Energy Information
in crustal rocks. Rock density is a physical characteristic that is governed by the chemical composition (in situ minerals) and pore spaces of a specific rock or rock type.1...
Drilling Large Diameter Holes in Rocks Using Multiple Laser Beams
Drilling Large Diameter Holes in Rocks Using Multiple Laser Beams (504) Drilling Large Diameter Holes in Rocks Using Multiple Laser Beams (504) Richard Parker,. Parker Geoscience Consulting, LLC, Arvada, Colorado, USA; Zhiyue Xu and Claude Reed, Argonne National Laboratory, Argonne, Illinois, USA; Ramona Graves, Department of Petroleum Engineering, Colorado School of Mines, Golden, Colorado, USA; Brian Gahan and Samih Batarseh, Gas Technology Institute, Des Plaines, Illinois, USA ABSTRACT Studies on drilling petroleum reservoir rocks with lasers show that modern infrared lasers have the capability to spall (thermally fragment), melt and vaporize natural earth materials with the thermal spallation being the most efficient rock removal mechanism. Although laser irradiance as low as 1000 W/cm 2 is sufficient to spall rock, firing the
Analysis of cause and mechanism for injection-induced seismicity at the Geysers Geothermal Field, California
rock from the Geysers Geothermal Field, California. Int. J.strain at The Geysers geothermal field. Ph.D. dissertation,Subsidence at The Geysers geothermal field, N. California
Rutqvist, Jonny; Oldenburg, Curtis
Fermilab Central Computing Facility: Energy conservation report and mechanical systems design optimization and cost analysis study
This report is developed as part of the Fermilab Central Computing Facility Project Title II Design Documentation Update under the provisions of DOE Document 6430.1, Chapter XIII-21, Section 14, paragraph a. As such, it concentrates primarily on HVAC mechanical systems design optimization and cost analysis and should be considered as a supplement to the Title I Design Report date March 1986 wherein energy related issues are discussed pertaining to building envelope and orientation as well as electrical systems design.
Krstulovich, S.F.
Rock Sampling | Open Energy Information
Rock Sampling Rock Sampling Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Rock Sampling Details Activities (13) Areas (13) Regions (1) NEPA(0) Exploration Technique Information Exploration Group: Field Techniques Exploration Sub Group: Field Sampling Parent Exploration Technique: Field Sampling Information Provided by Technique Lithology: Rock samples are used to define lithology. Field and lab analyses can be used to measure the chemical and isotopic constituents of rock samples. Stratigraphic/Structural: Provides information about the time and environment which formed a particular geologic unit. Microscopic rock textures can be used to estimate the history of stress and strain, and/or faulting. Hydrological: Isotope geochemistry can reveal fluid circulation of a geothermal system.
Energy from hot dry rock
The Hot Dry Rock Geothermal Energy Program is described. The system, operation, results, development program, environmental implications, resource, economics, and future plans are discussed. (MHR)
Hendron, R.H.
The economics of heat mining: An analysis of design options and performance requirements of hot dry rock (HDR) geothermal power systems
A generalized economic model was developed to predict the breakeven price of HDR generated electricity. Important parameters include: (1) resource quality--average geothermal gradient ({sup o}C/km) and well depth, (2) reservoir performance--effective productivity, flow impedance, and lifetime (thermal drawdown rate), (3) cost components--drilling, reservoir formation, and power plant costs and (4) economic factors--discount and interest rates, taxes, etc. Detailed cost correlations based on historical data and results of other studies are presented for drilling, stimulation, and power plant costs. Results of the generalized model are compared to the results of several published economic assessments. Critical parameters affecting economic viability are drilling costs and reservoir performance. For example, high gradient areas are attractive because shallower well depths and/or lower reservoir production rates are permissible. Under a reasonable set of assumptions regarding reservoir impedance, accessible rock volumes and surface areas, and mass flow rates (to limit thermal drawdown rates to about 10 C per year), predictions for HDR-produced electricity result in competitive breakeven prices in the range of 5 to 9 cents/kWh for resources having average gradients above 50 C/km. Lower gradient areas require improved reservoir performance and/or lower well drilling costs.
Mechanical Design, Analysis, and Testing of a Two-Bladed Wind Turbine Hub
Researchers at the National Wind Technology Center (NWTC) in Golden, Colorado, began performing the Unsteady Aerodynamics Experiment in 1993 to better understand the unsteady aerodynamics and structural responses of horizontal-axis wind turbines. The experiment consists of an extensively instrumented, downwind, three-bladed, 20-kilowatt wind turbine. In May 1995, I received a request from the NWTC to design a two-bladed hub for the experiment. For my thesis, I present the results of the mechanical design, analysis, and testing of the hub. The hub I designed is unique because it runs in rigid, teetering, or independent blade-flapping modes. In addition, the design is unusual because it uses two servomotors to pitch the blades independently. These features are used to investigate new load reduction, noise reduction, blade pitch optimization, and yaw control techniques for two-bladed turbines. I used a methodology by G. Phal and W. Bietz to design the hub. The hub meets all the performance specifications except that it achieves only 90% of the specified teeter range. In my thesis, I focus on the analysis and testing of the hub body. I performed solid-mechanics calculations, ran a finite-element analysis simulation, and experimentally investigated the structural integrity of the hub body.
Cotrell, J.
Pressurized thermal shock probabilistic fracture mechanics sensitivity analysis for Yankee Rowe reactor pressure vessel
The Nuclear Regulatory Commission (NRC) requested Oak Ridge National Laboratory (ORNL) to perform a pressurized-thermal-shock (PTS) probabilistic fracture mechanics (PFM) sensitivity analysis for the Yankee Rowe reactor pressure vessel, for the fluences corresponding to the end of operating cycle 22, using a specific small-break-loss- of-coolant transient as the loading condition. Regions of the vessel with distinguishing features were to be treated individually -- upper axial weld, lower axial weld, circumferential weld, upper plate spot welds, upper plate regions between the spot welds, lower plate spot welds, and the lower plate regions between the spot welds. The fracture analysis methods used in the analysis of through-clad surface flaws were those contained in the established OCA-P computer code, which was developed during the Integrated Pressurized Thermal Shock (IPTS) Program. The NRC request specified that the OCA-P code be enhanced for this study to also calculate the conditional probabilities of failure for subclad flaws and embedded flaws. The results of this sensitivity analysis provide the NRC with (1) data that could be used to assess the relative influence of a number of key input parameters in the Yankee Rowe PTS analysis and (2) data that can be used for readily determining the probability of vessel failure once a more accurate indication of vessel embrittlement becomes available. This report is designated as HSST report No. 117.
Dickson, T.L.; Cheverton, R.D.; Bryson, J.W.; Bass, B.R.; Shum, D.K.M.; Keeney, J.A. [Oak Ridge National Lab., TN (United States)
Analysis of reservoir heterogeneities due to shallowing-upward cycles in carbonate rocks of the Pennsylvanian Wahoo Limestone of Northeastern Alaska. Annual report, October 1990--September 1991
The primary objective of this project is to develop an integrated database to characterize reservoir heterogeneities resulting from numerous small-scale shallowing-upward cycles (parasequences) comprising the carboniferous Pennsylvanian Wahoo Limestone. The Wahoo Limestone is the upper formation of an extensive carbonate platform sequence of the Carboniferous Lisburne Group which is widely exposed in the Brooks Range and is a widespread hydrocarbon reservoir unit in the subsurface of the North Slope of Alaska. A principal goal is to determine lateral and vertical variations in the complex mosaic of carbonate facies comprising the Wahoo Limestone. This report presents the preliminary results of research accomplished by a team of specialists in carbonate petrology, biostratigraphy, and diagenesis during the 1990--1991 fiscal year.It includes a summary of regional geological framework studies, a discussion conodont analyses, an overview of diagenetic studies, a brief description of progress in computerized database development, and appendices containing some of the new data on petrographic analyses, conodont analyses, and locality and sample information. Our correlation scheme, which uses cyclic stratigraphy, biostratigraphy, and cement stratigraphy, will allow interpretation of the depositional history and paleogeographic evolution of the region. We have developed predictive facies models and will make paleogeographic maps to illustrate different stages in the history of the Wahoo carbonate ramp. Our detailed analyses of the Wahoo Limestone will provide a basis for interpreting correlative rocks in the adjacent subsurface of the coastal plain of ANWR, a potential hydrocarbon lease-sale area. In a broader sense, our work will provide an excellent generic example of carbonate shallowing-upward cycles which typify carbonate sediments.
Watts, K.
Analysis of reservoir heterogeneities due to shallowing-upward cycles in carbonate rocks of the Pennsylvanian Wahoo Limestone of Northeastern Alaska
In vivo evaluation of a new method for chemical analysis of volatile components in the respiratory gas of mechanically ventilated patients
Using the volatile anaesthetic isoflurane as a marker substance a gas chromatographic method for analysis of exhaled gas in mechanically ventilated patients was evaluated. Twelve patients with and 10 patients without preceding isoflurane exposure ... Keywords: breath analysis, isoflurane, mechanical ventilation
J. K. Schubert; I. Esteban-Loos; K. Geiger; J. Guttmann
Rock Sampling At Socorro Mountain Area (Armstrong, Et Al., 1995) | Open
Armstrong, Et Al., 1995) Armstrong, Et Al., 1995) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Rock Sampling At Socorro Mountain Area (Armstrong, Et Al., 1995) Exploration Activity Details Location Socorro Mountain Area Exploration Technique Rock Sampling Activity Date Usefulness not indicated DOE-funding Unknown Notes Corresponding Socorro caldera Carboniferous rocks were studied in the field in 1988-1992-Renault later completed geochemistry and silica-crystallite geothermometry, Armstrong petrographic analysis and cathodoluminescence, Oscarson SEM studies, and John Repetski (USGS, Reston, Virgina) conodont stratigraphy and color and textural alteration as guides to the carbonate rocks' thermal history. The carbonate-rock classification used in this
Gage for measuring displacements in rock samples
A gage for measuring diametral displacement within a rock sample for use in a rock mechanics laboratory and in the field, comprises a support ring housing a linear variable differential transformer, a mounting screw, and a leaf spring. The mounting screw is adjustable and defines a first point of contact with the rock sample. The leaf spring has opposite ends fixed to the inner periphery of the mounting ring. An intermediate portion of the leaf spring projecting radially inward from the ring is formed with a dimple defining a second point of contact with the sample. The first and second points of contact are diametrically opposed to each other. The LVDT is mounted in the ring with its axis parallel to the line of measurement and its core rod received in the dimple of the leaf spring. Any change in the length of the line between the first and second support points is directly communicated to the LVDT. The leaf spring is rigid to completely support lateral forces so that the LVDT is free of all load for improved precision.
Holcomb, David J. (Albuquerque, NM); McNamee, Michael J. (Albuquerque, NM)
A gage for measuring diametral displacement within a rock sample for use in a rock mechanics laboratory and in the field, comprises a support ring housing a linear variable differential transformer (LVDT), a mounting screw, and a leaf spring. The mounting screw is adjustable and defines a first point of contact with the rock sample. The leaf spring has opposite ends fixed to the inner periphery of the mounting ring. An intermediate portion of the leaf spring projecting radially inward from the ring is formed with a dimple defining a second point of contact with the sample. The first and second points of contact are diametrically opposed to each other. The LVDT is mounted in the ring with its axis parallel to the line of measurement and its core rod received in the dimple of the leaf spring. Any change in the length of the line between the first and second support points is directly communicated to the LVDT. The leaf spring is rigid to completely support lateral forces so that the LVDT is free of all load for improved precision.
Holcomb, D.J.; McNamee, M.J.
A Phased Array Approach to Rock Blasting
A series of laboratory-scale simultaneous two-hole shots was performed in a rock simulant (mortar) to record the shock wave interference patterns produced in the material. The purpose of the project as a whole was to evaluate the usefulness of phased array techniques of blast design, using new high-precision delay technology. Despite high-speed photography, however, we were unable to detect the passage of the shock waves through the samples to determine how well they matched the expected interaction geometry. The follow-up mine-scale tests were therefore not conducted. Nevertheless, pattern analysis of the vectors that would be formed by positive interference of the shockwaves from multiple charges in an ideal continuous, homogeneous, isotropic medium indicate the potential for powerful control of blast design, given precise characterization of the target rock mass.
Leslie Gertsch; Jason Baird
Post Rock | Open Energy Information
Rock Rock Jump to: navigation, search Name Post Rock Facility Post Rock Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner Wind Capital Group Developer Wind Capital Group Energy Purchaser Westar Energy Location Ellsworth KS Coordinates 38.87269233°, -98.33059788° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.87269233,"lon":-98.33059788,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Rock Sampling At Florida Mountains Area (Brookins, 1982) | Open Energy
source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Rock Sampling At Florida Mountains Area (Brookins, 1982) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Rock Sampling At Florida Mountains Area (Brookins, 1982) Exploration Activity Details Location Florida Mountains Area Exploration Technique Rock Sampling Activity Date Usefulness not indicated DOE-funding Unknown Notes Radiogenic heat production analysis from U,Th,K concentrations. References D. G. Brookins (1982) Potassium, Uranium, Thorium Radiogenic Heat Contribution To Heat Flow In The Precambrian And Younger Silicic Rocks Of The Zuni And Florida Mountains, New Mexico (Usa)
A Viscoelastic-Viscoplastic Analysis of Fiber Reinforced Polymer Composites Undergoing Mechanical Loading and Temperature Changes
This study presents a combined viscoelastic (VE)-viscoplastic (VP) analysis for Fiber Reinforced Polymer (FRP) composites subject to simultaneous mechanical load and conduction of heat. The studied FRP composites consist of unidirectional fibers, which are considered as linearly elastic with regards to their mechanical response, and isotropic polymeric matrix, which shows viscoelastic-viscoplastic response under various stresses and temperatures. Due to the viscoelastic and viscoplastic behavior of the polymeric matrix, the overall FRP composites exhibit a combined time-dependent and inelastic behavior. A simplified micromechanical model, consisting of a unit-cell with four fiber and matrix subcells, is formulated to homogenize the overall heat conduction and viscoelastic-viscoplastic responses of the FRP composites. The micromechanical model is compatible with a displacement based finite element (FE) and is implemented at the Gaussian integration points within the continuum finite elements, which is useful for analyzing the overall time-dependent response of FRP composite structures under various boundary conditions. The Schapery nonlinear integral model combined with the Perzyna viscoplastic model is used to describe the viscoelastic-viscoplastic response of the polymer constituents. An integrated time integration algorithm is formulated at the micromechanics level in order to solve the nonlinear viscoelastic-viscoplastic constitutive model at the matrix subcells and obtain the overall nonlinear response of the FRP. The viscoelastic-viscoplastic micromechanical model is validated usingexperimental data on off-axis glass/epoxy FRP composites available in literature. The overall response of the FRP composites determined from the simplified micromechanical model is also compared with the ones generated from microstructures of FRP with various fiber arrangements dispersed in homogeneous polymer matrix. The microstructural models of the FRP with detailed fiber arrangements are generated using FE. The effects of thermal stresses, due to the mismatches in the coefficient of thermal expansions of the fibers and polymeric matrix, and stress concentrations/discontinuities near the fiber and matrix interfaces on the overall thermo-mechanical deformation of FRP composites are studied using the two micromechanical models discussed above. Finally, an example of structural analysis is performed on a polymeric smart sandwich composite beam, having FRP skins and polymeric foam core with piezoelectric sensors integrated to the FRP skins, undergoing three point bending at an elevated temperature. The creep displacement is compared to experimental data available in literature.
Jeon, Jaehyeuk
Analysis of the Isolated SecA DEAD Motor Suggests a Mechanism for Chemical?Mechanical Coupling
The preprotein cross-linking domain and C-terminal domains of Escherichia coli SecA were removed to create a minimal DEAD motor, SecA-DM. SecA-DM hydrolyzes ATP and has the same affinity for ADP as full-length SecA. The crystal structure of SecA-DM in complex with ADP was solved and shows the DEAD motor in a closed conformation. Comparison with the structure of the E. coli DEAD motor in an open conformation (Protein Data Bank ID 2FSI) indicates main-chain conformational changes in two critical sequences corresponding to Motif III and Motif V of the DEAD helicase family. The structures that the Motif III and Motif V sequences adopt in the DEAD motor open conformation are incompatible with the closed conformation. Therefore, when the DEAD motor makes the transition from open to closed, Motif III and Motif V are forced to change their conformations, which likely functions to regulate passage through the transition state for ATP hydrolysis. The transition state for ATP hydrolysis for the SecA DEAD motor was modeled based on the conformation of the Vasa helicase in complex with adenylyl imidodiphosphate and RNA (Protein Data Bank ID 2DB3). A mechanism for chemical-mechanical coupling emerges, where passage through the transition state for ATP hydrolysis is hindered by the conformational changes required in Motif III and Motif V, and may be promoted by binding interactions with the preprotein substrate and/or other translocase domains and subunits.
Nithianantham, Stanley; Shilton, Brian H. (UWO)
Rock physics at Los Alamos Scientific Laboratory
Rock physics refers to the study of static and dynamic chemical and physical properties of rocks and to phenomenological investigations of rocks reacting to man-made forces such as stress waves and fluid injection. A bibliography of rock physics references written by LASL staff members is given. Listing is by surname of first author. (RWR)
Hot Dry Rock - Summary
Hot Dry Rock adds a new flexibility to the utilization of geothermal energy. Almost always the approach has been to limit that utilization to places where there is a natural source of water associated with a source of heat. Actually, the result was that steam was mined. Clearly there are much larger heat resources available which lack natural water to transport that energy to the surface. Also, as is found in hydrothermal fields being mined for steam, the water supply finally gets used up. There is a strong motive in the existing capital investment to revitalize those resources. Techniques for introducing, recovering and utilizing the water necessary to recover the heat from below the surface of the earth is the subject of this session. Implicit in that utilization is the ability to forecast with reasonable accuracy the busbar cost of that energy to the utility industry. The added element of supplying the water introduces costs which must be recovered while still supplying energy which is competitive. Hot Dry Rock technology can supply energy. That has been proved long since. The basic barrier to its use by the utility industry has been and remains proof to the financial interests that the long term cost is competitive enough to warrant investment in a technology that is new to utility on-grid operations. As the opening speaker for this session states, the test that is underway will ''simulate the operations of a commercial facility in some ways, but it will not show that energy from HDR can be produced at a variety of locations with different geological settings''. Further, the Fenton Hill system is a research facility not designed for commercial production purposes, but it can give indications of how the system must be changed to provide economic HDR operations. And so it is that we must look beyond the long term flow test, at the opportunities and challenges. Proving that the huge HDR resources can be accessed on a worldwide scale must involve the construction of additional sites, preferably to the specifications of the now Federal geothermal community. These facilities will have to be engineered to produce and market energy at competitive prices. At the same time, we must not rest on our technological laurels, though they be many. Design and operational techniques have been conceived which could lead to improved economics and operations for HDR. These must be pursued and where merit is found, vigorously pursued. Accelerated research and development ought to include revolutionary drilling techniques, reservoir interrogation, and system modeling to assure the competitiveness and geographical diversity of applications of HDR. Much of this work will be applicable to the geothermal industry in general. More advanced research ought to include such innovations as the utilization of other operating fluids. Supercritical carbon dioxide and the ammonia/water (Kalina) cycle have been mentioned. But even as the near and more distant outlook is examined, today's work was reported in the HDR session. The start-up operations for the current test series at the Fenton Hill HDR Pilot Plant were described. The surface plant is complete and initial operations have begun. While some minor modifications to the system have been required, nothing of consequence has been found to impede operations. Reliability, together with the flexibility and control required for a research system were shown in the system design, and demonstrated by the preliminary results of the plant operations and equipment performance. Fundamental to the overall success of the HDR energy resource utilization is the ability to optimize the pressure/flow impedance/time relationships as the reservoir is worked. Significant new insights are still being developed out of the data which will substantially affect the operational techniques applied to new systems. However, again, these will have to be proved to be general and not solely specific to the Fenton Hill site. Nevertheless, high efficiency use of the reservoir without unintended reservoir grow
Tennyson, George P. Jr.
Adsorption of water vapor on reservoir rocks
Progress is reported on: adsorption of water vapor on reservoir rocks; theoretical investigation of adsorption; estimation of adsorption parameters from transient experiments; transient adsorption experiment -- salinity and noncondensible gas effects; the physics of injection of water into, transport and storage of fluids within, and production of vapor from geothermal reservoirs; injection optimization at the Geysers Geothermal Field; a model to test multiwell data interpretation for heterogeneous reservoirs; earth tide effects on downhole pressure measurements; and a finite-difference model for free surface gravity drainage well test analysis.
Thermo-Mechanical Analysis of Coated Particle Fuel Experiencing a Fast Control Rod Ejection Transient
A rapid increase of the temperature and the mechanical stress is expected in TRISO coated particle fuel that experiences a fast Total Control Rod Ejection (CRE) transient event. During this event the reactor power in the pebble bed core increases significantly for a short time interval. The power is deposited instantly and locally in the fuel kernel. This could result in a rapid increase of the pressure in the buffer layer of the coated fuel particle and, consequently, in an increase of the coating stresses. These stresses determine the mechanical failure probability of the coatings, which serve as the containment of radioactive fission products in the Pebble Bed Reactor (PBR). A new calculation procedure has been implemented at the Idaho National Laboratory (INL), which analyzes the transient fuel performance behavior of TRISO fuel particles in PBRs. This early capability can easily be extended to prismatic designs, given the availability of neutronic and thermal-fluid solvers. The full-core coupled neutronic and thermal-fluid analysis has been modeled with CYNOD-THERMIX. The temperature fields for the fuel kernel and the particle coatings, as well as the gas pressures in the buffer layer, are calculated with the THETRIS module explicitly during the transient calculation. Results from this module are part of the feedback loop within the neutronic-thermal fluid iterations performed for each time step. The temperature and internal pressure values for each pebble type in each region of the core are then input to the PArticle STress Analysis (PASTA) code, which determines the particle coating stresses and the fraction of failed particles. This paper presents an investigation of a Total Control Rod Ejection (TCRE) incident in the 400 MWth Pebble Bed Modular reactor design using the above described calculation procedure. The transient corresponds to a reactivity insertion of $3 (~2000 pcm) reaching 35 times the nominal power in 0.5 seconds. For each position in the core the coated particle temperature and the stress history during a TCRE transient has been computed and the fuel failure probability has been quantified.
Ortensi, J.; Brian Boer; Abderrafi M. Ougouag
Simulation of blasting induced rock motion using spherical element models
Control of the rock motion associated with blasting can have significant economic benefits. For example, surface coal mining can be made more efficient if the overburden material can be cast further with explosives, leaving less work for mechanical equipment. The final muck pile shape in very type of surface and underground blasting is controlled by the blasting induced motion of the rock. A theoretically sound method of predicting rock motion will be beneficial to understanding the blasting process. Discrete element methods have been used for some time to predict rock motion resulting from blasting. What all of these approaches had in common was the use of polygonal elements with corners and sides as well as aspect ratio. Reasonably good results were obtained but treatment of the interactions of the corners and sides of elements was a computationally intensive process that made long simulations with many elements expensive to perform. The use of spherical elements showed increased efficiency but lacked the mechanisms for treating the bulking of the rock mass. The computer program developed was converted from an explicit code to an event-driven code and some bulking mechanisms were added that allowed spherical elements to exert a torque on other spherical elements with which contact was made. The architecture of this program and its event-driven nature made it difficult to vectorize for efficient execution on vector processing machines. A new code called DMC (Distinct Motion Code) has been developed this past year. DMC was designed and written especially to take advantage of super computer vector processing capabilities. This paper will discuss the use of DMC to perform accurate rock motion calculations with very reasonable computation times. 9 refs., 7 figs., 3 tabs.
Taylor, L.M.; Preece, D.S. (Hibbitt, Karlsson and Sorensen, Providence, RI (USA); Sandia National Labs., Albuquerque, NM (USA))
Thermal conductivity of rocks associated with energy extraction from hot dry rock geothermal systems
Results of thermal conductivity measurements are given for 14 drill core rock samples taken from two exploratory HDR geothermal wellbores (maximum depth of 2929 m (9608 ft) drilled into Precambrian granitic rock in the Jemez Mountains of northern New Mexico. These samples have been petrographically characterized and in general represent fresh competent Precambrian material of deep origin. Thermal conductivities, modal analyses, and densities are given for all core samples studied under dry and water-saturated conditions. Additional measurements are reported for several sedimentary rocks encountered in the upper 760 m (2500 ft) of that same region. A cut-bar thermal conductivity comparator and a transient needle probe were used for the determinations with fused quartz and Pyroceram 9606 as the standards. The maximum temperature range of the measurements was from the ice point to 250/sup 0/C. The measurements on wet, water-saturated rock were limited to the temperature range below room temperature. Conductivity values of the dense core rock samples were generally within the range from 2 to 2.9 W/mK at 200/sup 0/C. Excellent agreement was achieved between these laboratory measurements of thermal conductivity and those obtained by in situ measurements used in the HDR wellbores. By using samples of sufficient thickness to provide a statistically representative heat flow path, no difference between conductivity values and their temperature coefficients for orthogonal directions (heat flow parallel or perpendicular to core axis) was observed. This isotropic behavior was even found for highly foliated gneissic specimens. Estimates of thermal conductivity based on a composite dispersion analysis utilizing pure minerallic phase conductivities and detailed modal analyses usually agreed to within 9 percent of the experimental values.
Sibbitt, W.L.; Dodson, J.G.; Tester, J.W.
Diurnal temperature range for a doubled carbon dioxide concentration experiment: Analysis of possible physical mechanisms
An analysis of the results of a climate simulation for a doubling of atmospheric carbon dioxide concentration over the European region is reported. Physical mechanisms are sought which could explain possible changes in the diurnal temperature range (DTR) under conditions of increased atmospheric greenhouse gas content. We show that an important contribution to changes in DTR is given by soil mositure. In areas where soil moisture increases due to an increase in precipitation there is a positive change in latent heat flux and a decrease in sensible heat flux. As a result, in areas with increasing soil moisture, the increase in maximum daytime temperature will be smaller than that in minimum temperature, thereby causing a decrease in the DTR. The opposite occurs for areas which undergo soil drying. This process amplifies the effect of cloud changes on surface solar and infrared radiation and dominates the direct effect of downward infrared radiation associated with increasing greenhouse gas concentration. Because the soil water content is largely controlled by precipitation, our results are consistent with early observational findings of negative correlation between changes in precipitation and in diurnal temperature range.
Verdecchia, M.; Visconti, G.; Giorgi, F.; Marinucci, M.R. [Universita`degli Studi, L`Aquila (Italy)]|[National Center for Atmospheric Research, Boulder, CO (United States)
Mechanical and thermal analysis of beryllium windows for RF cavities in a muon cooling channel
Thin beryllium windows (foils) may be utilized to increase shunt impedance of closed-cell RF cavities. These windows are subject to ohmic heating from RF currents. The resulting temperature gradients in the windows can produce out of plane displacements that detune the cavity frequency. The window displacement can be reduced or eliminated by pre-stressing the foils in tension. Because of possible variations during manufacture, it is important to quantify the actual prestress of a Be window before it is put into service. We present the thermal and mechanical analyses of such windows under typical operating conditions and describe a simple non-destructive means to quantify the pre-stress using the acoustic signature of a window. Using finite element analysis, thin plate theory and physical measurements of the vibration modes of a window we attempted to characterize the actual Be window pre-stress in a small number of commercially sourced windows (30% of yield strength is typical). This method can be used for any window material and size, but this study focused on 16 cm diameter Be Windows ranging in thickness from 125 microns to 508 microns and with varying pre-stresses. The method can be used to nondestructively test future Be windows for the desired prestress.
Li, Derun; Ladran, A.; Lozano, D.; Rimmer, R.
Financial Analysis of Incentive Mechanisms to Promote Energy Efficiency: Case Study of a Prototypical Southwest Utility
Many state regulatory commissions and policymakers want utilities to aggressively pursue energy efficiency as a strategy to mitigate demand and energy growth, diversify the resource mix, and provide an alternative to building new, costly generation. However, as the National Action Plan for Energy Efficiency (NAPEE 2007) points out, many utilities continue to shy away from aggressively expanding their energy efficiency efforts when their shareholder's fundamental financial interests are placed at risk by doing so. Thus, there is increased interest in developing effective ratemaking and policy approaches that address utility disincentives to pursue energy efficiency or lack of incentives for more aggressive energy efficiency efforts. New regulatory initiatives to promote increased utility energy efficiency efforts also affect the interests of consumers. Ratepayers and their advocates are concerned with issues of fairness, impacts on rates, and total consumer costs. From the perspective of energy efficiency advocates, the quid pro quo for utility shareholder incentives is the obligation to acquire all, or nearly all, achievable cost-effective energy efficiency. A key issue for state regulators and policymakers is how to maximize the cost-effective energy efficiency savings attained while achieving an equitable sharing of benefits, costs and risks among the various stakeholders. In this study, we modeled a prototypical vertically-integrated electric investor-owned utility in the southwestern US that is considering implementing several energy efficiency portfolios. We analyze the impact of these energy efficiency portfolios on utility shareholders and ratepayers as well as the incremental effect on each party when lost fixed cost recovery and/or utility shareholder incentive mechanisms are implemented. A primary goal of our quantitative modeling is to provide regulators and policymakers with an analytic framework and tools that assess the financial impacts of alternative incentive approaches on utility shareholders and customers if energy efficiency is implemented under various utility operating, cost, and supply conditions.We used and adapted a spreadsheet-based financial model (the Benefits Calculator) which was developed originally as a tool to support the National Action Plan for Energy Efficiency (NAPEE). The major steps in our analysis are displayed graphically in Figure ES- 1. Two main inputs are required: (1) characterization of the utility which includes its initial financial and physical market position, a forecast of the utility?s future sales, peak demand, and resource strategy to meet projected growth; and (2) characterization of the Demand-Side Resource (DSR) portfolio ? projected electricity and demand savings, costs and economic lifetime of a portfolio of energy efficiency (and/or demand response) programs that the utility is planning or considering implementing during the analysis period. The Benefits Calculator also estimates total resource costs and benefits of the DSR portfolio using a forecast of avoided capacity and energy costs. The Benefits Calculator then uses inputs provided in the Utility Characterization to produce a ?business-as usual? base case as well as alternative scenarios that include energy efficiency resources, including the corresponding utility financial budgets required in each case. If a decoupling and/or a shareholder incentive mechanism are instituted, the Benefits Calculator model readjusts the utility?s revenue requirement and retail rates accordingly. Finally, for each scenario, the Benefits Calculator produces several metrics that provides insights on how energy efficiency resources, decoupling and/or a shareholder incentive mechanism impacts utility shareholders (e.g. overall earnings, return on equity), ratepayers (e.g., average customer bills and rates) and society (e.g. net resource benefits).
Mechanical fatigue analysis of gold microbeams for RF-MEMS applications by pull-in voltage monitoring
This work is focused on the reliability of gold microcantilevers under the effect of mechanical fatigue. A dedicated device for testing the material is designed and built; the material degradation is monitored during the tests by means of a novel technique ... Keywords: Failure analysis, Fatigue, Gold, MEMS, Reliability
G. Pasquale; A. Som�; A. Ballestra
Department of Mechanical and Nuclear Engineering Spring 2012 Heavy-Duty Diesel Engine Friction Reduction Testing and Analysis
PENNSTATE Department of Mechanical and Nuclear Engineering Spring 2012 Heavy-Duty Diesel Engine Friction Reduction Testing and Analysis Overview Volvo Group Powertrain Engineering is interested in increasing fuel efficiency through the reduction of parasitic friction and pumping losses. A test cell
Demirel, Melik C.
Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field...
Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field Investigations Of In Situ...
Incentives Analysis Supply Mix Purchased Power Natural GasIncentives Analysis Arizona Public Service Nuclear Purchased Power Nevada Power Purchased Power Nuclear Coal Renewables Renewables Natural Gas
Rock units in regional tectonic analysis - Springer
sins, chains of volcanoes, faulting, uplift and subsidence of crustal blocks, and so on. The causative processes remain unseen, and can only be inferred ftom�...
Zeolitization Of Intracaldera Sediments And Rhyolitic Rocks In The 1.25 Ma
Zeolitization Of Intracaldera Sediments And Rhyolitic Rocks In The 1.25 Ma Zeolitization Of Intracaldera Sediments And Rhyolitic Rocks In The 1.25 Ma Lake Of Valles Caldera, New Mexico, Usa Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Zeolitization Of Intracaldera Sediments And Rhyolitic Rocks In The 1.25 Ma Lake Of Valles Caldera, New Mexico, USA Details Activities (0) Areas (0) Regions (0) Abstract: Quantitative X-ray diffraction analysis of about 80 rhyolite and associated lacustrine rocks has characterized previously unrecognized zeolitic alteration throughout the Valles caldera resurgent dome. The alteration assemblage consists primarily of smectite-clinoptilolite-mordenite-silica, which replaces groundmass and fills voids, especially in the tuffs and lacustrine rocks. Original rock textures are routinely preserved. Mineralization typically extends to
Department of Mechanical Engineering Fall 2011 Pratt & Whitney Engine Low Pressure Turbine Vane Cluster Analysis
Turbine Vane Cluster Analysis Overview The goal was to provide Pratt & Whitney with a detailed finite
Laser Rock Perforation Demo - The NE Multimedia Collection
rock perforation demo High power laser beam can be used in oil well completion application for perforating oil reservoir rock and increasing rock's permeability for high oil...
PARKER-HEADGATE ROCK & PARKER-GILA 161-kV TRANSMISSION LINE Cross Arm Repair and Helicopter Staging Areas Figure 1. Project Location Project Location j PARKER-HEADGATE ROCK &...
An Analysis of a Combined Hardware-software Mechanism for Speculative Loads
This paper describes a simple hardware mechanism and related compiler support for softwarecontrolled speculative loads. The compiler issues speculative load instructions based on anticipated data references and the ability of the memory system to hide memory latency in high-performance processors. The architectural support for such a mechanism is simple and minimal, yet handles faults gracefully. We have simulated three speculative load mechanisms based on a MIPS processor and a detailed memory system. The results of scientific kernel loops indicate that speculative load techniques can hide memory latency effectively.
Stefanos Damianakis; Kai Li; Anne Rogers
Mechanical Engineering Safety Note: Analysis and Control of Hazards Associated with NIF Capacitor Module Events
The NIF capacitor module was reviewed with respect to pressure venting and shrapnel containment during failures. A modified module concept was proposed that would adequately vent the pressure, yet be effective at containing shrapnel. Two large vents are provided on each side of the module. These have fixed vent areas, and are immediately accessible for pressure venting at the beginning of a pressure transient. A shrapnel shield is located on the outside of each vent opening forming a chute. The chute contains a collimator. This increases the number of bounces that shrapnel must take on the way out, and directs the shrapnel to the trap beneath. The trap contains a depth of clear pine, sufficient to completely absorb the energy of even the most energetic fragment considered. Based on a review of the evidence from past capacitor failures at the FANTM facility at Sandia National Laboratory, Albuquerque, and additional theoretical estimates, the peak pressure generated in the module during explosive events was estimated to be less than 40 psig. This internal pressure in the FANTM module appears to be tolerable, as only minor damage to the module and to internal components was observed after events. The new module concept proposed here provides increased venting area, fully available at the initiation of an event. It is expected that even less damage would be observed if an event occurred in a module with this design. The module joints and connections were formally reviewed with respect to their tolerance to a brief internal pressure as high as 40 psig. With minor modifications that have been incorporated into the design, the module was shown to maintain its integrity during such events. Some of the calculations performed estimated the quantity of dielectric oil that could be involved in a capacitor failure. It was determined that a very small amount of the available oil would contribute to the explosive event, on the order of 500 g or less. This is a small fraction of the total free oil available in a capacitor (approximately 10,900 g), on the order of 5% or less. The estimates of module pressure were used to estimate the potential overpressure in the capacitor bays after an event. It was shown that the expected capacitor bay overpressure would be less than the structural tolerance of the walls. Thus, it does not appear necessary to provide any pressure relief for the capacitor bays. The ray tracing analysis showed the new module concept to be 100% effective at containing fragments generated during the events. The analysis demonstrated that all fragments would impact an energy absorbing surface on the way out of the module. Thus, there is high confidence that energetic fragments will not escape the module. However, since the module was not tested, it was recommended that a form of secondary containment on the walls of the capacitor bays (e.g., 1.0 inch of fire-retardant plywood) be provided. Any doors to the exterior of the capacitor bays should be of equivalent thickness of steel or suitably armed with a thickness of plywood. Penetrations in the ceiling of the interior bays (leading to the mechanical equipment room) do not require additional protection to form a secondary barrier. The mezzanine and the air handling units (penetrations lead directly to the air handling units) provide a sufficient second layer of protection.
Brereton, S
Hot dry rock geothermal heat extraction
A man-made geothermal reservoir has been created at a depth of 2.7 km in hot, dry granite by hydraulic fracturing. The system was completed by directionally drilling a second well in close proximity with the top of the vertical fracture. In early 1978 heat was extracted from this reservoir for a period of 75 days. During this period thermal power was produced at an average rate of 4 MW(t). Theoretical analysis of th measured drawdown suggests a total fracture heat transfer area of 16,000 m/sup 2/. Viscous impedance to through-flow declined continuously so that at the end of the experiment this impedance was only one-fifth its initial value. Water losses to the surrounding rock formation also decreased continuously, and eventually this loss rate was less than 1% of the circulated flow rate. Geochemical analyses suggest that, with scale up of the heat transfer area and deeper, hotter reservoirs, hot dry rock reservoirs can ultimately produce levels of power on a commercial scale.
Murphy, H.D.
Hot dry rock energy project
A proof-of-concept experimental project by the Los Alamos Scientific Laboratory endeavors to establish the feasibility of exploitation of the thermal energy contained in the earth's crust where such energy and a transporting fluid have not been juxtaposed in nature. A region of high heat flow and apparently unfaulted basement rock formation was selected. Two boreholes, drilled to a total depth of about 3 km (10,000 ft) and penetrating about 2.5 km (7500 ft) into the Precambrian formation, to a rock temperature of 200/sup 0/C, have been connected at depth by a hydraulically fractured zone to form the heat extraction surface. Energy was extracted at a rate of 3.2 MW(t) with water temperature of 132/sup 0/C during a 96-h preliminary circulating test run performed late in September 1977. This paper traces the progress of the project, summarizes procedures and salient events, and references detailed reports and specialized topics.
Analysis of an Interactive Instability Mechanism for the Antarctic Circumpolar Wave
An interactive atmosphere�ocean instability mechanism that reproduces some salient properties of the observed Antarctic Circumpolar Wave and also its manifestation in the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Mark 2 ...
Peter G. Baines; Wenju Cai
Analysis and sourcing of the mechanical equipment required for a ceramic pot filter production facility
Research was done into identifying and sourcing the mechanical equipment required for manufacturing ceramic pot filters, specifically for use in the Pure Home Water factory in Northern Ghana. The pieces of equipment ...
Getachew, Julian (Julian B.)
Analysis of the structure and mechanisms of extinction of a counterflow methanol-air diffusion flame
Numerical calculations were performed to determine the structure and to clarify the extinction mechanisms of diffusion flames stabilized between counterflowing streams of methanol and air. The calculations were performed at a value of the thermodynamic pressure equal to 1 atmosphere, with different values for the rate of strain and with two different chemical kinetic mechanisms, mechanism a and mechanism b. Mechanism a and mechanism b have the same set of elementary reactions, but the rate constants for these elementary reactions were obtained from two different references. If mechanism a is used, the authors conclude that at low rates of strain the concentration of CH/sub 2/OH and HCO are in steady state and, if partial equilibrium is assumed for certain reactions, there exist algebraic relations among the concentrations of the radicals OH, H, and O. As the rate of strain is increased, HCO is no longer in steady state and no solution was obtained for a strain rate greater than 521 s/sup -1/. However, if mechanism b is used, the concentration of HCO alone is in steady state, and there also exist algebraic relations among the concentrations of the radicals OH, H, and O. As the rate of strain is increased, no solution was obtained for a strain rate greater than 168 s/sup -1/, and the authors speculate that extinction of the flame is due to a large value of the activation energy for a reaction controlling the pyrolysis of CH/sub 2/OH to CH/sub 2/O.
Seshadri, K.; Trevino, C.; Smooke, M.D.
Relative Permeability of Fractured Rock
Contemporary understanding of multiphase flow through fractures is limited. Different studies using synthetic fractures and various fluids have yielded different relative permeability-saturation relations. This study aimed to extend the understanding of multiphase flow by conducting nitrogen-water relative permeability experiments on a naturally-fractured rock from The Geysers geothermal field. The steady-state approach was used. However, steady state was achieved only at the endpoint saturations. Several difficulties were encountered that are attributed to phase interference and changes in fracture aperture and surface roughness, along with fracture propagation/initiation. Absolute permeabilities were determined using nitrogen and water. The permeability values obtained change with the number of load cycles. Determining the absolute permeability of a core is especially important in a fractured rock. The rock may change as asperities are destroyed and fractures propagate or st rain harden as the net stresses vary. Pressure spikes occurred in water a solute permeability experiments. Conceptual models of an elastic fracture network can explain the pressure spike behavior. At the endpoint saturations the water relative permeabilities obtained are much less than the nitrogen gas relative permeabilities. Saturations were determined by weighing and by resistivity calculations. The resistivity-saturation relationship developed for the core gave saturation values that differ by 5% from the value determined by weighing. Further work is required to complete the relative permeability curve. The steady-state experimental approach encountered difficulties due to phase interference and fracture change. Steady state may not be reached until an impractical length of time. Thus, unsteady-state methods should be pursued. In unsteady-state experiments the challenge will be in quantifying rock fracture change in addition to fluid flow changes.
Mark D. Habana
Rock bed storage with heat pump. Final report
The study, Rock Bed Storage with Heat Pump, established the feasibility of mating a heat pump to a rock bed storage to effect optimal performance at the lowest cost in single family residences. The operating characteristics of off-the-shelf components of heat pump/rock bed storage systems were studied, and the results were used to formulate configurations of representative systems. These systems were modeled and subsequently analyzed using the TRNSYS computer program and a life cycle cost analysis program called LCCA. A detailed load model of a baseline house was formulated as part of the TRNSYS analysis. Results of the analysis involved the development of a technique to confine the range of heat pump/rock bed storage systems to those systems which are economical for a specific location and set of economic conditions. Additionally, the results included a comparison of the detailed load model with simple UA models such as the ASHRAE bin method. Several modifications and additions were made to the TRNSYS and LCCA computer programs during the course of the study.
Remmers, H.E.; Mills, G.L.
Determination of Carbon Release Mechanisms in the DIII-D Divertors from Analysis of C I Line Profiles
During typical operation of the DIII-D tokamak, physical and chemical sputtering are the most important mechanisms for release of carbon at the divertor targets [Nuclear Fusion 42 614 (2002)]. Modeling of C I spectral line profiles is discussed as a technique for evaluating the relative contribution of each mechanism and is applied to several types of DIII-D discharges. The line shapes are symmetric and have shifts of about -0.03 if they are produced solely from molecular dissociation, but they exhibit distinct asymmetries and shifts approaching -0.20 if generated by physical sputtering. Modeled profiles must, in general, take account of both mechanisms in order to match experimental data. An alternate approach to distinguishing between the two processes, which relies on the relative intensities of C I, CD, and C2 emissions, is examined in light of conclusions drawn from the line-shape analysis.
Isler, Ralph C [ORNL; Brooks, N. H. [General Atomics, San Diego; West, W. P. [General Atomics, San Diego; McLean, A. G. [University of Toronto Institute for Aerospace Studies
Dispersivity as an oil reservoir rock characteristic
The main objective of this research project is to establish dispersivity, {alpha}{sub d}, as an oil reservoir rock characteristic and to use this reservoir rock property to enhance crude oil recovery. A second objective is to compare the dispersion coefficient and the dispersivity of various reservoir rocks with other rock characteristics such as: porosity, permeability, capillary pressure, and relative permeability. The dispersivity of a rock was identified by measuring the physical mixing of two miscible fluids, one displacing the other in a porous medium. 119 refs., 27 figs., 12 tabs.
Menzie, D.E.; Dutta, S.
Neutron Production from the Fracture of Piezoelectric Rocks
A theoretical explanation is provided for the experimental evidence that fracturing piezoelectric rocks produces neutrons. The elastic energy micro-crack production ultimately yields the macroscopic fracture. The mechanical energy is converted by the piezoelectric effect into electric field energy. The electric field energy decays via radio frequency (microwave) electric field oscillations. The radio frequency electric fields accelerate the condensed matter electrons which then collide with protons producing neutrons and neutrinos.
A. Widom; J. Swain; Y. N. Srivastava
Widom, A; Srivastava, Y N
States Million dollars Billion dollars xiv Energy Efficiency IncentivesEnergy Efficiency Incentives Analysis Introduction Many statestate and federal government taxes). xvi Energy Efficiency Incentives
Error analysis of motion transmission mechanisms : design of a parabolic solar trough.
??This thesis presents the error analysis pertaining to the design of an innovative solar trough for use in solar thermal energy generation fields. The research� (more)
Koniski, Cyril (Cyril A.)
Thermodynamic modeling of transcription: sensitivity analysis differentiates biological mechanism from mathematical model-induced effects
as: Dresch et al. : Thermodynamic modeling of transcription:ARTICLE Open Access Thermodynamic modeling of transcription:on the analysis of thermodynamic models, which have been
Dresch, Jacqueline M; Liu, Xiaozhou; Arnosti, David N; Ay, Ahmet
ORNL Quasi-Static Mechanical Characterization and Analysis: FY09 Annual Report to TARDEC
The testing and evaluation of candidate glasses for transparent armor served as a primary goal. Other armor ceramics were evaluated too, in support of the development of innovative test methods, whose use will ultimately help in the improvement of armor ceramics or help in better predicting their ballistic performance. The following summarizes this report and this year's work: (1) The elastic properties of a spherical indenter affect the forces necessary to initiate fracture in a target ceramics. The lower the elastic modulus of an indenter material, the easier (i.e., lower forces required) it is to initiate fracture. This implies the fracture initiation of an armor ceramic will depend on the elastic properties of a projectile material, and that this effect, represented by the Dundurs Parameter, can be managed to guide improvement of both armor and projectile materials. (2) The largest flaws in a population dictate both contact damage and fracture initiations. This implies the ballistic response of armor ceramics will improve if those large flaws are precluded from appearing in the materials during their processing. (3) Failure stress dependence on effective area for Hertzian indentation was developed. Such analysis is adaptable to predict ballistically produced fracture initiation as a function of projectile material and projectile size. (4) A simple, quick, and inexpensive test method was developed to measure the apparent yield stress of armor ceramics. This is significant because yield stress is used as input in ballistic models, and yield stress is traditionally measured using (complex, timeconsuming, and expensive) shock physics experiments. (5) Radial confinement increases the necessary indentation forces to initiate fracture and yield-like responses in ceramics. Ballistic improvement of an armor ceramic will occur if the ceramic can be compressively pre-stressed. (6) The median crack produced by a Hertzian indent is associated with a dramatic increase in target ceramic compliance. More so than any other produced damage mechanism. This suggests that a ballistically induced median crack in an armor ceramic may be associated with the dwell penetration event. (7) Glass exhibits tensile strength that is very much dependent on the amount of material, the side being tested (air versus tin if a float glass), and where it is being tensile stressed (in the middle or near an edge). The management of these effects will improve ballistic resistance of transparent armor (or any ceramic armor that is undergoing deflection as a consequence of a ballistic impact). (8) Plasma-arc heat treatment is a quick and relatively inexpensive method to improve the strength of glass. It is implementable into the production line for the mass production of glass. Increased strain-to-failure and bending deflections are concomitant with increased strength, and therefore, ballistic resistance is improvable using this method. (9) The Hertzian stress field at high contact stresses is very similar to the stress field from a ballistic impact. This is significant because the results from Hertzian indentation measurements have the prospect of being used as input in ballistic models to predict dwell conditions. (10) The understanding of glass densification and fragmentation behaviors are aided by piezo-Raman spectroscopy and quasi-static, high-energy fracture. Continued refinement of these test methods will improve the understanding of glass impact resistance. (11) In addition to glass, strength-size scaling was evident in SiC and B{sub 4}C. Previously proposed strength dependencies on rate from shock experiments may instead be explained by this strength-size scaling effect. (12) The quantification of strength-size scaling in armor ceramics clearly shows there is no single strength value that can be used to describe that ceramic. A ballistic modeler can therefore use more appropriate failure stress value(s) as input to predict deflection and expanding cavity responses in the ceramic target. These follow-on efforts are recommended based on the above statem
Wereszczak, Andrew A [ORNL; Kirkland, Timothy Philip [ORNL; Strong, Kevin T [ORNL; Holmquist, Timothy [SWRI
Hot Dry Rock Overview at Los Alamos
The Hot Dry Rock (HDR) geothermal energy program is a renewable energy program that can contribute significantly to the nation's balanced and diversified energy mix. Having extracted energy from the first Fenton Hill HDR reservoir for about 400 days, and from the second reservoir for 30 days in a preliminary test, Los Alamos is focusing on the Long Term Flow Test and reservoir studies. Current budget limitations have slowed preparations thus delaying the start date of that test. The test is planned to gather data for more definitive reservoir modeling with energy availability or reservoir lifetime of primary interest. Other salient information will address geochemistry and tracer studies, microseismic response, water requirements and flow impedance which relates directly to pumping power requirements. During this year of ''preparation'' we have made progress in modeling studies, in chemically reactive tracer techniques, in improvements in acoustic or microseismic event analysis.
Berger, Michael; Hendron, Robert H.
Analysis on Modulation Principle of Mechanical Spring Valve Block-Type Pulse Jet
To take full advantage of the bottom-hole hydraulic energy to improve the drilling rate, it is proposed the technique assumption that using mechanical spring valve periodically is to block the fluid pathway, and modulating pulse jet is to increase the ... Keywords: block type, pulse jet, drilling rate, water hammer, experimental study
Ni Hongjian; Zhu Lihong; Huo Hongjun; Tang Zhiwen
Structural analysis of an LMFBR shield assembly duct under thermo-mechanical and seismic loads
This paper describes the stress analysis performed to assess structural adequacy of the Clinch River Breeder Reactor (CRBR) core removable shield assemblies. Removable shield assemblies are located in the peripheral region of the core (between blanket assemblies and the fixed radial shield), and are subjected to severe cross-sectional thermal gradients and seismic loads requiring a relatively complex duct load pad design. For cost-effectiveness, the analysis was conducted in two stages. First, an elasto-plastic seismic stress analysis was performed using a detailed nonlinear finite element model (with gaps) of the load pad configuration. Next, in order to determine the total strain accumulation and the creep-fatigue damage the maximum seismic stresses combined with the ''worst'' thermal stresses from a single assembly model were used to perform a simplified inelastic analysis using two sets of material properties to bound the changing material conditions during reactor operation. This work demonstrated the necessity and applicability of the two simplified analysis techniques in elevated temperature structural design, i.e., the treatment of time-dependent degradation of material properties due to temperature and nuclear irradiation, and the use of time-independent finite element stress analysis results to perform a simplified creep-fatigue analysis.
Malik, S.N.; Sazawal, V.K.
Hot Dry Rock; Geothermal Energy
The commercial utilization of geothermal energy forms the basis of the largest renewable energy industry in the world. More than 5000 Mw of electrical power are currently in production from approximately 210 plants and 10 000 Mw thermal are used in direct use processes. The majority of these systems are located in the well defined geothermal generally associated with crustal plate boundaries or hot spots. The essential requirements of high subsurface temperature with huge volumes of exploitable fluids, coupled to environmental and market factors, limit the choice of suitable sites significantly. The Hot Dry Rock (HDR) concept at any depth originally offered a dream of unlimited expansion for the geothermal industry by relaxing the location constraints by drilling deep enough to reach adequate temperatures. Now, after 20 years intensive work by international teams and expenditures of more than $250 million, it is vital to review the position of HDR in relation to the established geothermal industry. The HDR resource is merely a body of rock at elevated temperatures with insufficient fluids in place to enable the heat to be extracted without the need for injection wells. All of the major field experiments in HDR have shown that the natural fracture systems form the heat transfer surfaces and that it is these fractures that must be for geothermal systems producing from naturally fractured formations provide a basis for directing the forthcoming but, equally, they require accepting significant location constraints on HDR for the time being. This paper presents a model HDR system designed for commercial operations in the UK and uses production data from hydrothermal systems in Japan and the USA to demonstrate the reservoir performance requirements for viable operations. It is shown that these characteristics are not likely to be achieved in host rocks without stimulation processes. However, the long term goal of artificial geothermal systems developed by systematic engineering procedures at depth may still be attained if high temperature sites with extensive fracturing are developed or exploited. [DJE -2005
Establishment of Stress-Permeabilty relationship of fractured rock mass by numerical modeling
Office of Scientific and Technical Information (OSTI)
Accepted for publication in International Journal of Rock Mechanics & Mining Sciences Accepted for publication in International Journal of Rock Mechanics & Mining Sciences Stress-Dependent Permeability of Fractured Rock Masses: A Numerical Study Ki-Bok Min *1 , J Rutqvist 2 , Chin-Fu Tsang 2 , and Lanru Jing 1 1 Engineering Geology and Geophysics Research Group, Royal Institute of Technology (KTH), Stockholm, Sweden 2 Earth Sciences Division, Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA, USA * corresponding author. Tel.: +46-8-790-7919; fax: +46-8-790-6810. E-mail address: email@example.com (Ki-Bok Min) 1 Abstract We investigate the stress-dependent permeability issue in fractured rock masses considering the effects of nonlinear normal deformation and shear dilation of fractures using a two-dimensional
Analysis and Simulation of Mechanical Trains Driven by Variable Frequency Drive Systems
Induction motors and Variable Frequency Drives (VFDs) are widely used in industry to drive machinery trains. However, some mechanical trains driven by VFD-motor systems have encountered torsional vibration problems. This vibration can induce large stresses on shafts and couplings, and reduce the lifetime of these mechanical parts. Long before the designed lifetime, the mechanical train may encounter failure. This thesis focuses on VFDs with voltage source rectifiers for squirrel-cage induction motors of open-loop Volts/Hertz and closed-loop Field Oriented Control (FOC). First, the torsional vibration problems induced by VFDs are introduced. Then, the mathematical model for a squirrel-cage induction motor is given. Two common control methods used in VFD are discussed - open-loop Volts/Hertz and closed-loop FOC. SimPowerSystems and SimMechanics are used as the modeling software for electrical systems and mechanical systems respectively. Based on the models and software, two interface methods are provided for modeling the coupled system. A simple system is tested to verify the interface methods. The study of open-loop Volts/Hertz control method is performed. The closed-form of electromagnetic torque sideband frequency due to Pulse Width Modulation is given. A torsional resonance case is illustrated. The effects of non-ideal power switches are studied, which shows little in uence on the system response but which uses little energy consumption. A study of a non-ideal DC bus indicates that a DC bus voltage ripple can also induce a big torsional vibration. Next, the study of the closed-loop FOC control method is presented. Simulation for a complete VFD machinery train is performed. With the recti er and DC bus dynamic braking, the system shows a better performance than the ideal-DC bus case. Lastly, a parametric study of the FOC controller is performed. The effects of primary parameters are discussed. The results indicate that some control parameters (i.e. speed ramps, proportional gain in speed PI controller) are also responsible for the mechanical torsional vibration.
Han, Xu
Error analysis of motion transmission mechanisms : design of a parabolic solar trough
This thesis presents the error analysis pertaining to the design of an innovative solar trough for use in solar thermal energy generation fields. The research was a collaborative effort between Stacy Figueredo from Prof. ...
Preliminary assessment of high-resistivity cap-rock shale in the Frio Formation of the Texas Gulf Coast. Annual report
Mapping of high resistivity cap rock shales in the Frio Formation of the Texas Gulf Coast shows that few areas of thin cap rock occur in the upper Texas Gulf Coast, and more extensive, thicker cap rock occurs in the lower Texas Gulf Coast. Increases in (1) maximum shale resistivity, (2) unstable minerals (volcanic rock fragments, detrital carbonate grains), and (3) authigenic cementation parallel the increase in cap rock from the upper to the lower Gulf Coast. Similarity in cap rock distribution in two major Frio deltaic depocenters is not evident. Facies analysis of regional cross sections in the lower Texas Gulf Coast and of cross sections in Sarita East field, Kenedy County, shows preferential development of cap rock in the delta-front/slope facies of the Norias delta system. Sand content of the cap rock interval varies from 23 to 41 percent in part of Sarita East field, suggesting that if cap rock is due to authigenic cementation, such sands may act as fluid conduits during mineralization. Cap rock is rarely developed in the shale-rich prodelta and distal delta-front facies. High resistivity cap rock shales have been considered a result of authigenic calcite cementation, but definite evidence for this origin is lacking. Preliminary mineralogic analyses of well cuttings have not yielded satisfactory results. Analysis of core through cap rock and non-cap rock intervals will be required to determine the mineralogic variability within each interval and to accurately assess any mineralogic control of the high resistivity log response.
Finley, R.J.
Comprehensive Mechanisms for Combustion Chemistry: An Experimental and Numerical Study with Emphasis on Applied Sensitivity Analysis
This project was an integrated experimental/numerical effort to study pyrolysis and oxidation reactions and mechanisms for small-molecule hydrocarbon structures under conditions representative of combustion environments. The experimental aspects of the work were conducted in large-diameter flow reactors, at 0.3 to 18 atm pressure, 500 to 1100 K temperature, and 10-2 to 2 seconds reaction time. Experiments were also conducted to determine reference laminar flame speeds using a premixed laminar stagnation flame experiment and particle image velocimetry, as well as pressurized bomb experiments. Flow reactor data for oxidation experiments include: (1)adiabatic/isothermal species time-histories of a reaction under fixed initial pressure, temperature, and composition; to determine the species present after a fixed reaction time, initial pressure; (2)species distributions with varying initial reaction temperature; (3)perturbations of a well-defined reaction systems (e.g. CO/H2/O2 or H2/O2)by the addition of small amounts of an additive species. Radical scavenging techniques are applied to determine unimolecular decomposition rates from pyrolysis experiments. Laminar flame speed measurements are determined as a function of equivalence ratio, dilution, and unburned gas temperature at 1 atm pressure. Hierarchical, comprehensive mechanistic construction methods were applied to develop detailed kinetic mechanisms which describe the measurements and literature kinetic data. Modeling using well-defined and validated mechanisms for the CO/H2/Oxidant systems and perturbations of oxidation experiments by small amounts of additives were also used to derive absolute reaction rates and to investigate the compatibility of published elementary kinetic and thermochemical information. Numerical tools were developed and applied to assess the importance of individual elementary reactions to the predictive performance of the developed mechanisms and to assess the uncertainties in elementary rate constant evaluations.
Dryer, Frederick L.
DOE hot dry rock program
Hydraulic fracturing has been used to create and subsequently to enlarge the first hot dry rock heat-extraction loop at Fenton Hill, New Mexico. Encouraging results prompted the DOE to expand this project into a program of national scope. The elements of that Program and their present status are discussed. Emphasis is given the ongoing Fenton Hill Project where techniques and information developed in the existing research system will soon be used to produce a multiply-fractured engineering system in hotter rock at the same site. Recent results from research loop operation and progress in constructing the engineering system are reported. Although acoustic mapping and system geometry indicate that the primary hydraulic fractures are essentially vertical, relatively low fracturing pressure and absence of a sharp breakdown suggest that at Fenton Hill fracture initiation occurs by reopening of old natural fractures rather than by initiation of new ones. Flow patterns and temperature behavior suggest opening of additional old fractures as the loop is operated. Except where the hot fluid leaves the crack system to enter the production well, flow impedances are very low without either artificial propping or inflation by pressurization.
Nunz, G.J.
Investigation of moisture effects on interfacial properties of an epoxy matrix composite by dynamic mechanical analysis
The interfacial properties of polymer matrix composites are critical to the retention of the mechanical properties of the composites in a wet environment. The objective of this study is to investigate the effect of moisture on the interfacial properties of glass bead-epoxy composites by measuring mechanical properties obtained through dynamic mechanical testing. The viscoelastic material properties of glass bead-composites, including glassy and rubbery moduli and the loss tangent (tanb) were measured. In order to characterize the relationship between dynamic mechanical properties and interfacial structure, composites with different interfacial structures were tested and the results were compared. The different interfacial structures are created by treating or not treating the glass beads with a silane coupling agent before the production of the composites. The plain epoxy matrix was also tested. The sorption behavior of the specimens was monitored by recording the percent weight gain of the water uptake periodically. In general, the measured properties reflect the effect of moisture on the properties of matrix, composites, and interphase. For the plain matrix, moisture reduces Tg, by about 15,,C, and reduces tans at Tg. These are all characteristic of plasticization of the matrix. The effects of water on composites strongly depend on the interfacial structure of the composites. The interphase with silane coupling agent provides better interfacial adhesion, thus improving stress transfer between matrix and reinforcement. The silane also reduces the mobility of the epoxy network near the glass surface. This hypothesis was supported by the greater E', higher Ea. and smaller tans at Tg for silane-treated composite compared to corresponding properties for the untreated composite. Water seems to weaken the interfacial strength of composites since water reduces the rubbery modulus of the composites but not of the plain matrix. Water reduces the interfacial bond strength less for silane-treated composites than for untreated composites. In addition, composites with poorer interfacial bond strength showed larger "additional" tan8 peaks next to the (X-transition. If we assume that poor interfacial bond strength leads to more interfacial cracks or voids, then the tans spectrum may be useful for characterizing the extent of cracking.
Wang, Jo-Yu
Rock Energy Cooperative (Illinois) | Open Energy Information
Cooperative (Illinois) Jump to: navigation, search Name Rock Energy Cooperative Place Illinois Utility Id 16196 References EIA Form EIA-861 Final Data File for 2010 - File220101...
Hot dry rock fracture propagation and reservoir characterization
North America's largest hydraulic fracturing opeations have been conducted at Fenton hill, New mexico to creae hot dry rock geothermal reservoirs. Microearthquakes induced by these fracturing operations were measured with geophones. The large volume of rock over which the microearthquakes were distributed indicates a mechanism of hydraulic stimulation which is at odds with conventional fracturing theory, which predicts failure along a plane which is perpendicular to the least compressive earth stress. Shear slippage along pre-existing joints in the rock is more easily induced than conventional tensile failure, particularly when the difference between minimum and maximum earth stresses is large and the pre-existing joints are oriented at angles between 30 and 60)degree) to the principal earth stresses, and a low viscosity fluid like water is injected. Shear slippage results in local redistribution of stresses, which allows a branching, or dendritic, stimulation pattern to evolve, in agreement with the patterns of microearthquake locations. Field testing of HDR reservoirs at the Fenton Hill site shows that significant reservoir growth occurred as energy was extracted. Tracer, microseismic, and geochemical measurements provided the primary quantitative evidence for the increases in accessible reservoir volume and fractured rock surface area. These temporal increases indicate that augmentation of reservoir heat production capacity in hot dry rock system occurred. For future reservoir testing, Los Alamos is developing tracer techniques using reactive chemicals to track thermal fronts. Recent studies have focused on the kinetics of hydrolysis of derivatives of bromobenzene, which can be used in reservoirs as hot as 275)degree)C.
Murphy, H.; Fehler, M.; Robinson, B.; Tester, J.; Potter, R.; Birdsell, S.
Introduction to Finite Element Modeling Engineering analysis of mechanical systems have been addressed by deriving differential
such as equilibrium, conservation of energy, conservation of mass, the laws of thermodynamics, Maxwell's equations the fundamental ideas of the FEM · Know the behavior and usage of each type of elements covered in this course of the FEM (don't misuse the FEM - a numerical tool) Finite Element Analysis A typical finite element
Lin, Liwei
A finite element model for hygro-thermo-mechanical analysis of masonry walls with FRP reinforcement
Modeling the effects of humidity and temperature gradients on the structural behavior of masonry walls reinforced with fiber reinforced polymer (FRP) composite is of great importance. Study of interfacial stresses, in particular, is a key factor in predicting ... Keywords: FRP reinforced masonry, Moisture and temperature, Multi-layered permeable structure, Structural analysis
Mehran Khoshbakht; Mark W. Lin
Mechanism for high hydrogen storage capacity on metal-coated carbon nanotubes: A first principle analysis
The hydrogen adsorption and binding mechanism on metals (Ca, Sc, Ti and V) decorated single walled carbon nanotubes (SWCNTs) are investigated using first principle calculations. Our results show that those metals coated on SWCNTs can uptake over 8 wt% hydrogen molecules with binding energy range -0.2--0.6 eV, promising potential high density hydrogen storage material. The binding mechanism is originated from the electrostatic Coulomb attraction, which is induced by the electric field due to the charge transfer from metal 4s to 3d. Moreover, we found that the interaction between the H{sub 2}-H{sub 2} further lowers the binding energy. - Graphical abstract: Five hydrogen molecules bound to individual Ca decorated (8, 0) SWCNT : a potential hydrogen-storage material. Highlights: Black-Right-Pointing-Pointer Each transition metal atom can adsorb more than four hydrogen molecules. Black-Right-Pointing-Pointer The interation between metal and hydrogen molecule is electrostatic coulomb attraction. Black-Right-Pointing-Pointer The electric field is induced by the charge transfer from metal 4s to metal 3d. Black-Right-Pointing-Pointer The adsorbed hydrogen molecules which form supermolecule can further lower the binding energy.
Lu, Jinlian; Xiao, Hong [Department of Physics and Institute for nanophysics and Rare-earth Luminescence, Xiangtan University, Xiangtan, Hunan Province 411105 (China)] [Department of Physics and Institute for nanophysics and Rare-earth Luminescence, Xiangtan University, Xiangtan, Hunan Province 411105 (China); Cao, Juexian, E-mail: email@example.com [Department of Physics and Institute for nanophysics and Rare-earth Luminescence, Xiangtan University, Xiangtan, Hunan Province 411105 (China)] [Department of Physics and Institute for nanophysics and Rare-earth Luminescence, Xiangtan University, Xiangtan, Hunan Province 411105 (China)
Schmid et al. Inclusion Behavior in Deforming Rocks Inclusion Behavior in Deforming Rocks
Schmid et al. Inclusion Behavior in Deforming Rocks Inclusion Behavior in Deforming Rocks Dani Podladchikov, PGP, University of Oslo, Norway Intro 1 #12;Schmid et al. Inclusion Behavior in Deforming Rocks Motivation 2 The single most useful thing to understand! #12;Schmid et al. Inclusion Behavior in Deforming
Cesare, Bernardo
Definition: Petrography Analysis | Open Energy Information
is the study of rocks. A petrographic analysis is an in depth investigation of the chemical and physical features of a particular rock sample. A complete analysis should include...
Fracture mechanics investigation of oil shale to aid in understanding the explosive fragmentation process. Final technical report, January 1983-July 1984
This report summarizes goals and findings achieved in developing technologies to improve the overall efficiency of oil shale recovery processes. The objectives are to (a) develop theoretical fracture mechanics tools that are applicable to transversely isotropic materials such as sedimentary rock, more particularly oil shale; and (b) develop a fracture mechanics test procedure that can be conveniently used for rock specimens. Such a test procedure would: utilize the geometry of a typical rock core for the test; require a minimum amount of specimen machining; and provide meaningful, reproducible data that corresponds well to test data obtained from conventional fracture mechanics tests. Critical review of the state-of-the-art of fracture mechanics on layered rocks has been completed. Recommendations are made for innovative and promising methods for oil shale fracture mechanics. Numerical and analytical studies of mixed mode fracture mechanics are investigated. Transversely isotropic properties of oil shale are input using isoparametric finite elements with singular elements at the crack tip. The model is a plate with an edge crack whose angle with the edge varies to study the effect of mixed mode fracture under various conditions. The three-dimensional plate is in tension, and stress, energy methods are used in the fracture analysis. Precracked disks of oil shale cored perpendicular to bedding planes are analyzed numerically. Stress intensity factors are determined by (i) strain energy method, and (ii) elliptic simulation method. 47 refs., 12 figs., 1 tab.
Chong, K.P.
The hot dry rock geothermal energy program
The paper presents a simplified description of the Department of Energy's Hot-Dry-Rock program conducted at Fenton Hill, New Mexico. What a hot-dry-rock resource is and what the magnitude of the resource is are also described.
Smith, M.C.
Comprehensive mechanisms for combustion chemistry: An experimental and numerical study with emphasis on applied sensitivity analysis
Over the last three years, this program has made significant progress on a number of problems: development of a data base for oxidation of the CO/H[sub 2]/O[sub 2] system; development and refinement of a comprehensive kinetic mechanism for the CO/H[sub 2]/O[sub 2] system; additional experiments on formaldehyde oxidation in the, comprehensive mechanistic studies inclusive of flow reactor results and literature results from static reactors, shock tubes, and flames, and identification of elementary reactions needing further study; mechanistic study of previously acquired APFR flow reactor data on ethanol oxidation, including an estimation of the branching ratios for C[sub 2]H[sub 5]0H + X, X= OH,H and identification of elementary reactions needing additional study; completion and mechanistic evaluation of the first insitu optical diapostic measurements of OH in the APFR; determinations of uni-molecular decomposition rate for 1,3,5-Trioxane at 700 to 800 K; seeded perturbation experiments on moist CO oxidation in flow reactors as a means to determine elementary rate constants for specific reactions; determination of elementary rates for CH[sub 4] + OH [yields] CH[sub 3] + H[sub 2]0 at 1026 and 1140 K, and C[sub 3]H[sub 6] + OH [yields] products at 1020 K; First experimental studies of the H[sub 2]/O[sub 2] reaction system in the VPFR at conditions between the extended second and third explosion limits.
Dryer, F.L.; Yetter, R.A.
Eagle Rock Geothermal Facility | Open Energy Information
Eagle Rock Geothermal Facility Eagle Rock Geothermal Facility Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Eagle Rock Geothermal Facility General Information Name Eagle Rock Geothermal Facility Facility Eagle Rock Sector Geothermal energy Location Information Location The Geysers, California Coordinates 38.826770222484°, -122.80002593994° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.826770222484,"lon":-122.80002593994,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Definition: Rock Sampling | Open Energy Information
Sampling Sampling Jump to: navigation, search Dictionary.png Rock Sampling Systematic rock sampling can be used to characterize a geothermal reservoir. The physical and chemical properties of rock samples provide important information for determining whether a power generation or heat utilization facility can be developed. Some general rock properties can be measured by visual inspection, but detailed properties require laboratory techniques. View on Wikipedia Wikipedia Definition A core sample is a cylindrical section of (usually) a naturally occurring substance. Most core samples are obtained by drilling with special drills into the substance, for example sediment or rock, with a hollow steel tube called a core drill. The hole made for the core sample is called the "core hole". A variety of core samplers exist to sample
Lawrence E. Carlson Professor of Mechanical Engineering
Education, American Society of Mechanical Engineers, pp. 31-33. Solar Stirling Engine 2Cam Rock Climbing Rooftop Bike Rack Drywall Screw Gun A Better Buckle #12;DESIGN FOR MANUFACTURABILITY The Course
Carlson, Lawrence E.
Analysis of transport mechanisms in dense fuel droplet sprays. Final report
the piezoelectric source plate and the rock surface. With aThe S^j sources were bonded to the rock surface with a fast-^ source plate was epoxied in position on the rock specimen.
Waters, K.H.
Molecular and somatic-cell genetic analysis of metal-resistance mechanisms in mammalian cells
Combined molecular genetic analyses and somatic cell systems were utilized to delineate factors involved in metal metabolism. Somatic cells derived by selection procedures using toxic heavy metals were used to define primary factors involved in acquisition of metal resistance. Such cell variants permitted isolation of the specific genes involved in conferring heavy metal binding proteins, the metallothioneins. (MT). These isolated genes provided the molecular probes to dissect the multiple levels of control and organization of this one set of genes responsible for metal resistance. Studies on the roles of MT in metal resistance used these variants and cell lines derived from human tumors to illustrate that MTs play an important but not exclusive role in cadmium detoxification. Studies on Cd/sup + +/ responses in human tumor derived cell lines showed several orders of magnitude differences in Cd/sup + +/ sensitivity in lines having similar MT responses. Analysis of cultured normal blood cell responses showed that the most Cd/sup + +/ resistant population, the granulocytes, did not produce significant quantities of MT. The results presented here further show a lack of correlation between MT and cytotoxic responses to Cd/sup + +/ in freshly cultured human leukemic peripheral blood cells. In these, enhanced Cd/sup + +/ uptake may be a factor determining enhanced sensitivity. Theses results together indicate that an adequate understanding of cellular responses to toxic metals will not be provided by elucidation of the role(s) of one or a few known metal binding proteins such as MT. Other factors and systems that modulate cellular uptake and sensitivity must first be defined.
Enger, M.D.; Hildebrand, C.E.; Walters, R.A.; Seagrave, J.C.; Barham, S.S.; Hoagland, H.C.
Analysis of a Window-Based Flow Control Mechanism based on TCP Vegas in Heterogeneous Network Environment
Another version of TCP called TCP Vegas has been proposed and studied in the literature. It can achieve better performance than the current TCP Reno. In our previous studies, steady-state behavior of a windowbased flow control mechanism based on TCP Vegas has been analyzed for a simple network topology. In this paper, we extend our analysis to a generic network topology where multiple bottleneck links exist. We first derive equi- librium values of a window size of a TCP connection and the number of packets waiting in a router's buffer in steady state. We also derive throughput of each TCP connection in steady state, and investigate the effect of control parameters of TCP Vegas on fairness among TCP connections. We then present several numerical examples, showing how control parameters of TCP Vegas should be configured for achieving both stability and better transient performance.
Keiichi Takagaki; Hiroyuki Ohsaki; Masayuki Murata
A comparative integrated transcript analysis and functional characterization of differential mechanisms for induction of liver hypertrophy in the rat
The main goal of the present work was to better understand the molecular mechanisms underlying liver hypertrophy (LH), a recurrent finding observed following acute or repeated drug administration to animals, using transcriptomic technologies together with the results from conventional toxicology methods. Administration of 5 terminated proprietary drug candidates from participating companies involved in the EU Innomed PredTox Project or the reference hepatotoxicant troglitazone to rats for up to a 14-day duration induced LH as the main liver phenotypic toxicity outcome. The integrated analysis of transcriptomic liver expression data across studies turned out to be the most informative approach for the generation of mechanistic models of LH. In response to a xenobiotic stimulus, a marked increase in the expression of xenobiotic metabolizing enzymes (XME) was observed in a subset of 4 studies. Accumulation of these newly-synthesized proteins within the smooth endoplasmic reticulum (SER) would suggest proliferation of this organelle, which most likely is the main molecular process underlying the LH observed in XME studies. In another subset of 2 studies (including troglitazone), a marked up-regulation of genes involved in peroxisomal fatty acid {beta}-oxidation was noted, associated with induction of genes involved in peroxisome proliferation. Therefore, an increase in peroxisome abundance would be the main mechanism underlying LH noted in this second study subset. Together, the use of transcript profiling provides a means to generate putative mechanistic models underlying the pathogenesis of liver hypertrophy, to distinguish between subtle variations in subcellular organelle proliferation and creates opportunities for improved mechanism-based risk assessment.
Boitier, Eric, E-mail: email@example.com [sanofi aventis R and D, Disposition, Safety and Animal Research, Vitry sur Seine (France); Amberg, Alexander [sanofi aventis R and D, Disposition, Safety and Animal Research, Frankfurt (Germany); Barbie, Valerie [Merck Serono S.A., Stratified Medicine, Geneva (Switzerland); Blichenberg, Arne [Nycomed GmbH, Institute for Pharmacology and Preclinical Drug Safety, Barsbuettel (Germany); Brandenburg, Arnd; Gmuender, Hans [Genedata AG, Basel (Switzerland); Gruhler, Albrecht [Novo Nordisk A/S, Protein Science, Malov (Denmark); McCarthy, Diane [Bio-Rad Laboratories, Hercules, CA (United States); Meyer, Kirstin; Riefke, Bjoern; Raschke, Marian [Bayer Schering Pharma AG, Investigational Toxicology, Berlin (Germany); Schoonen, Willem [MSD, Toxicology and Drug Disposition, Oss (Netherlands); Sieber, Maximilian [Universitaet Wuerzburg, Institut fuer Toxikologie, Wuerzburg (Germany); Suter, Laura [Hoffmann-La Roche Ltd., Investigative Toxicology, Basel (Switzerland); Thomas, Craig E. [Eli Lilly and Company, Investigative Toxicology, Indianapolis, IN (United States); Sajot, Nicolas [Servier, Drug Safety Assessment, Orleans-Gidy (France)
Aerobic enhanced oil recovery: analysis of the mechanisms and a pilot study
The technique that uses microorganisms to improve oil production in petroleum reservoirs is known as microbial enhanced oil recovery (MEOR). Aerobic microbial enhanced oil recovery is a method which is based on stimulating indigenous oil degrading bacteria by introducing oxygen (air) and nutrients into the injection water in an existing water flood. The primary emphasis is to promote biological growth in the oil/ water interface, which reduces the interfacial tension and mobilizes the oil. This process is proven to work in laboratory studies, and successful field tests have been reported in USSR. A pilot test on AMEOR has been initiated in the North Brock field in Oklahoma. The treatment, which consists of a continuous injection of air together with an appropriate nutrient supply, has been going on for seven months. So far no increase in oil production has been observed in the full field scale. However, well tests performed on each production well show an increase in oil production from two wells. This increase does not have any effect on the total oil production due to decline periods in the other wells. The most positive observation in the field test is an increase in the differential pressure observed right after the start of oxygen injection. This may be a result of reduced permeability to water in the oil bank, indicating an oil mobilization process in the reservoir. The same effect has also been observed in the laboratory core studies. The process is also proven to be time dependent and independent of the number of pore volumes flooded. It is concluded that it is too early in the process to experience any incremental oil production. The pressure increase may indicate that a mobilization process is going on and that it will only be a matter of time before any additional oil will be experienced in the field. This research involves an analysis of the pilot study in the North Brock field, in addition to a description of the AMEOR technique, effects and limitations. A comparison to other conventional MEOR techniques is also given.
Eide, Karen
Some approaches to rock mass hydrofracture theory
A new engineering method has been developed at the Leningrad Mining Institute for defining hot dry rock hydrofracturing parameters. It reflects the structural features of a real jointed rock mass, its gravity-tectonic components of the stress tensor and volume character of deformations, taking into account the inertial effects of hydrodynamics in the non-Darcy zone of radial fluid flow near the injection well, and conversion of the heat energy extracted from hot rock by circulating water partly into filtration-flow additional pressure. Results of calculations are compared to field experiments at Fenton Hill, NM, and are used for the first HDR circulation systems in the USSR.
Dyadkin, Yuri, D.
Future of hot dry rock geothermal energy systems
Where natural groundwater circulation does not exist, the obvious method of extracting heat from the earth's crust is to imitate nature by creating it. A means of doing so by hydraulic fracturing has been demonstrated. Alternatively, explosives or mechanical or chemical methods might be used to open circulation paths. However, where permeabilities are sufficient so that fluid loss is excessive, other approaches are also possible. The magnitude and distribution of hot dry rock and the variety of possible heat-extraction techniques make it appear inevitable that this energy supply will eventually be used on a large scale.
Rock of Ages | Open Energy Information
of Ages of Ages Jump to: navigation, search Name Rock of Ages Facility Rock of Ages Sector Wind energy Facility Type Small Scale Wind Facility Status In Service Owner Rock of Ages Energy Purchaser Rock of Ages Location Graniteville VT Coordinates 44.14668574°, -72.48180896° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":44.14668574,"lon":-72.48180896,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Rock bed heat accumulators. Final report
The principal objectives of the research program on rock bed heat accumulators (or RBHA) are: (1) to investigate the technical and economic feasibility of storing large amounts of thermal energy (in the tens of MWt range) at high temperature (up to 500/sup 0/C) over extended periods of time (up to 6 months) using native earth or rock materials; (2) to conduct studies to establish the performance characteristics of large rock bed heat accumulators at various power and temperature levels compatible with thermal conversion systems; and (3) to assess the materials and environmental problems associated with the operation of such large heat accumulators. Results of the study indicate that rock bed heat accumulators for seasonal storage are both technically and economically feasible, and hence could be exploited in various applications in which storage plays an essential role such as solar power and total energy systems, district and cogeneration heating systems.
Riaz, M.
Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field
source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field Investigations Of In Situ Geochemical Behavior Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field Investigations Of In Situ Geochemical Behavior Details Activities (5) Areas (2) Regions (0) Abstract: Two hot dry rock (HDR) geothermal energy reservoirs have been created by hydraulic fracturing of Precambrian granitic rock between two wells on the west flank of the Valles Caldera in the Jemez Mountains of northern New Mexico. Heat is extracted by injecting water into one well,
Rock Sampling At Zuni Mountains Nm Area (Brookins, 1982) | Open Energy
Zuni Mountains Nm Area (Brookins, 1982) Zuni Mountains Nm Area (Brookins, 1982) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Rock Sampling At Zuni Mountains Nm Area (Brookins, 1982) Exploration Activity Details Location Zuni Mountains Nm Area Exploration Technique Rock Sampling Activity Date Usefulness not indicated DOE-funding Unknown Notes Radiogenic heat production analysis from U,Th,K concentrations. References D. G. Brookins (1982) Potassium, Uranium, Thorium Radiogenic Heat Contribution To Heat Flow In The Precambrian And Younger Silicic Rocks Of The Zuni And Florida Mountains, New Mexico (Usa) Retrieved from "http://en.openei.org/w/index.php?title=Rock_Sampling_At_Zuni_Mountains_Nm_Area_(Brookins,_1982)&oldid=387056" Category: Exploration Activities
Experimental Estimation Of Energy Damping During Free Rocking Of Unreinforced Masonry Walls. First Results
This paper presents an ongoing experimental program on unreinforced masonry walls undergoing free rocking. Aim of the laboratory campaign is the estimation of kinetic energy damping exhibited by walls released with non?zero initial conditions of motion. Such energy damping is necessary for dynamic modelling of unreinforced masonry local mechanisms. After a brief review of the literature on this topic
Luigi Sorrentino; Renato Masiani; Stefano Benedetti
Pore Connectivity Effects on Solute Transport in Rocks
Retardation of nuclear contaminants in rock matrices can lead to long retention times, allowing substantial radionuclide decay prior to eventual release. Imbibition and diffusion into the rock matrix can move contaminants away from an active fracture, thereby contributing to their retardation. However, diffusive transport in some rocks may behave anomalously because of their sparsely connected porespace, in contrast to diffusion in rocks with denser pore connections. We examined imbibition of weakly sorbing tracers into welded tuff and Indiana sandstone, and water imbibition into metagraywacke and Berea sandstone. Tuff samples were initially equilibrated to 12% and 76% water (v/v) within controlled humidity chambers, while the other rocks were air-dried. For imbibition, one face was exposed to water, with or without tracer, and uptake was measured over time. Following imbibition, tracer concentration measurements were made at fine (1 mm) increments. Three anomalous results were observed: (1) Indiana sandstone and metagraywacke showed mass of imbibed water scaling as time{sup 0.26}, while tuff and Berea sandstone showed the more classical scaling with time{sup 0.05}; (2) tracer movement into dry (2% initial saturation) Indiana sandstone showed a dispersion pattern similar to that expected during tracer movement into moist (76% initial saturation) tuft and (3) tracer concentrations at the inlet face of the tuff sample were approximately twice those deeper inside the sample. The experiment was then modeled using random walk methods on a 3-D lattice with different values of pore coordination. Network model simulations that used a pore coordination of 1.49 for Indiana sandstone and 1.56 for metagraywacke showed similar temporal scaling, a result of their porespace being close to the percolation threshold. Tracer concentration profiles in Indiana sandstone and tuff were closely matched by simulations that used pore coordinations of 1.49 and 1.68, respectively, because of how low connectivity alters the accessible porosity in the vicinity of the inlet face. The study supports pore connectivity as a coherent explanation for the observed anomalies and demonstrates the utility of pore-scale modeling in elucidating mechanisms critical to radionuclide retardation in geological repositories.
Oinhong Hu
Analysis and Application of Sheppard�s Airflow Model to Predict Mechanical Orographic Lifting and the Occurrence of Mountain Clouds
Mechanically driven orographic lifting is important for air pollution dispersion and weather prediction, but the small dimensions of mountain peaks often prevent numerical weather models from producing detailed forecasts. Mechanical lifting in ...
Jan Kleissl; Richard E. Honrath; Diamantino V. Henriques
Deep drilling technology for hot crystalline rock
The development of Hot Dry Rock (HDR) geothermal systems at the Fenton Hill, New Mexico site has required the drilling of four deep boreholes into hot, Precambrian granitic and metamorphic rocks. Thermal gradient holes, four observation wells 200 m (600 ft) deep, and an exploration core hole 800 m (2400 ft) deep guided the siting of the four deep boreholes. Results derived from the exploration core hole, GT-1 (Granite Test No. 1), were especially important in providing core from the granitic rock, and establishing the conductive thermal gradient and heat flow for the granitic basement rocks. Essential stratigraphic data and lost drilling-fluid zones were identified for the volcanic and sedimentary rocks above the contact with the crystalline basement. Using this information drilling strategies and well designs were then devised for the planning of the deeper wells. The four deep wells were drilled in pairs, the shallowest were planned and drilled to depths of 3 km in 1975 at a bottom-hole temperature of nearly 200/sup 0/C. These boreholes were followed by a pair of wells, completed in 1981, the deepest of which penetrated the Precambrian basement to a vertical depth of 4.39 km at a temperature of 320/sup 0/C.
Rowley, J.C.
The nature of fire-cracked rock: new insights from ethnoarchaeological and laboratory experiments
Fire-cracked rock (FCR) is the archaeological by-product of the systemic use of hot rocks for cooking and heating purposes. As a record of various cooking and heating facilities, FCR has substantial potential for addressing research questions on past settlement and subsistence systems. To be able to address these questions requires reliable methods that can identify or infer how a given FCR was used. A series of ethnoarchaeological replication experiments are conducted in order to improve the understanding of the geothennodynamics of FCR production. FCR from two experimental data sets are cut to expose flat surfaces that are inspected for thermal-weathering characteristics under low-power magnification. Analytical results indicate that rock structure and the length of heat application have the most control over thermal weathering. The five most important rock structure characteristics are (1) strength of the bond between grains/crystals, (2) degree of porosity, (3) grain/crystal mineralogy, (4) presence of discontinuities, and (5) grain size; thin section analysis can identify these characteristics for any rock sample. The length of heat application varies dependent on the type of cooking or heating facility, for instance, a typical earth oven remains hot for a longer duration than a typical stone-boil facility; multiple uses of a rock in a facility also increases the sum total of heat application. In broad terms, experimental tests indicate igneous rock types withstand thermal weathering better than metamorphic or sedimentary rock types. Ethnoarchaeological results are applied to six archaeological FCR features, and provide new insights on the use-history of five of the features. Microscopic observations of archaeological FCR also all for the re-evaluation of the current model which explains the occurrence of various FCR shape types within features.
Jackson, Michael A
Rock-brine chemical interactions. Final report
The results of experimental interaction of powdered volcanic rock with aqueous solutions are presented at temperatures from 200 to 400/sup 0/C, 500 to 1000 bars fluid pressure, with reaction durations of approximately 30 days under controlled laboratory conditions. The aim of this research is to develop data on the kinetics and equilibria of rock solution interactions that will provide insight into the complex geochemical processes attending geothermal reservoir development, stimulation, and reinjection. The research was done in the Stanford Hydrothermal Lab using gold cell equipment of the Dickson design. This equipment inverts the solution rock mixture several times a minute to ensure thorough mixing. Solution samples were periodically withdrawn without interruption of the experimental conditions. The data from these experiments suggests a path dependent series of reactions by which geothermal fluids might evolve from meteoric or magmatic sources.
Smaller Footprint Drilling System for Deep and Hard Rock Environments; Feasibility of Ultra-High-Speed Diamond Drilling
The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high rotational speeds (greater than 10,000 rpm). The work includes a feasibility of concept research effort aimed at development that will ultimately result in the ability to reliably drill 'faster and deeper' possibly with smaller, more mobile rigs. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration (ROP) rock cutting with substantially lower inputs of energy and loads. The significance of the 'ultra-high rotary speed drilling system' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm - usually well below 5,000 rpm. This document provides the progress through two phases of the program entitled 'Smaller Footprint Drilling System for Deep and Hard Rock Environments: Feasibility of Ultra-High-Speed Diamond Drilling' for the period starting 30 June 2003 and concluding 31 March 2009. The accomplishments of Phases 1 and 2 are summarized as follows: (1) TerraTek reviewed applicable literature and documentation and convened a project kick-off meeting with Industry Advisors in attendance (see Black and Judzis); (2) TerraTek designed and planned Phase I bench scale experiments (See Black and Judzis). Improvements were made to the loading mechanism and the rotational speed monitoring instrumentation. New drill bit designs were developed to provided a more consistent product with consistent performance. A test matrix for the final core bit testing program was completed; (3) TerraTek concluded small-scale cutting performance tests; (4) Analysis of Phase 1 data indicated that there is decreased specific energy as the rotational speed increases; (5) Technology transfer, as part of Phase 1, was accomplished with technical presentations to the industry (see Judzis, Boucher, McCammon, and Black); (6) TerraTek prepared a design concept for the high speed drilling test stand, which was planned around the proposed high speed mud motor concept. Alternative drives for the test stand were explored; a high speed hydraulic motor concept was finally used; (7) The high speed system was modified to accommodate larger drill bits than originally planned; (8) Prototype mud turbine motors and the high speed test stand were used to drive the drill bits at high speed; (9) Three different rock types were used during the testing: Sierra White granite, Crab Orchard sandstone, and Colton sandstone. The drill bits used included diamond impregnated bits, a polycrystalline diamond compact (PDC) bit, a thermally stable PDC (TSP) bit, and a hybrid TSP and natural diamond bit; and (10) The drill bits were run at rotary speeds up to 5500 rpm and weight on bit (WOB) to 8000 lbf. During Phase 2, the ROP as measured in depth of cut per bit revolution generally increased with increased WOB. The performance was mixed with increased rotary speed, with the depth cut with the impregnated drill bit generally increasing and the TSP and hybrid TSP drill bits generally decreasing. The ROP in ft/hr generally increased with all bits with increased WOB and rotary speed. The mechanical specific energy generally improved (decreased) with increased WOB and was mixed with increased rotary speed.
TerraTek, A Schlumberger Company
Rock melting tool with annealer section
A rock melting penetrator is provided with an afterbody that rapidly cools a molten geological structure formed around the melting tip of the penetrator to the glass transition temperature for the surrounding molten glass-like material. An annealing afterbody then cools the glass slowly from the glass transition temperature through the annealing temperature range to form a solid self-supporting glass casing. This allows thermally induced strains to relax by viscous deformations as the molten glass cools and prevents fracturing of the resulting glass liner. The quality of the glass lining is improved, along with its ability to provide a rigid impermeable casing in unstable rock formations.
Bussod, Gilles Y. (Santa Fe, NM); Dick, Aaron J. (Oakland, CA); Cort, George E. (Montrose, CO)
Proceedings of the Workshop on Numerical Modeling of Thermohydrological Flow in Fractured Rock Masses, Feb. 19-20, 1980, Berkeley, CA
and fluid flow in the hydraulic fracturing process." Ph.D.depth by means of hydraulic fracturing." in Rock Mechanics:production by hydraulic fracturing, the focus of fracture
Witherspoon, P.A.
Category:Little Rock, AR | Open Energy Information
AR AR Jump to: navigation, search Go Back to PV Economics By Location Media in category "Little Rock, AR" The following 16 files are in this category, out of 16 total. SVFullServiceRestaurant Little Rock AR Entergy Arkansas Inc.png SVFullServiceRestauran... 71 KB SVHospital Little Rock AR Entergy Arkansas Inc.png SVHospital Little Rock... 69 KB SVLargeHotel Little Rock AR Entergy Arkansas Inc.png SVLargeHotel Little Ro... 70 KB SVLargeOffice Little Rock AR Entergy Arkansas Inc.png SVLargeOffice Little R... 71 KB SVMediumOffice Little Rock AR Entergy Arkansas Inc.png SVMediumOffice Little ... 68 KB SVMidriseApartment Little Rock AR Entergy Arkansas Inc.png SVMidriseApartment Lit... 70 KB SVOutPatient Little Rock AR Entergy Arkansas Inc.png SVOutPatient Little Ro...
Colloid-facilitated radionuclide transport in fractured porous rock
Numerical methods have been applied for the prediction of colloid-facilitated radionuclide transport through water-saturated fractured porous rock. The presence of colloids may enhance the transport of radionuclides in groundwater by reducing retardation effects. The colloids existing in the groundwater act as carriers, adsorbing radionuclides on their large surface area and moving faster than the average water velocity. With colloids present, the system consists of three phases, i. e., an aqueous phase, a carrier phase, and a stationary solid phase. In the basic model, one-dimensional advection in a single planar fracture of infinite extent is coupled with diffusion in the rock matrix perpendicular to the fracture. In this study, a full-equilibrium model was developed to describe the transport and fate of the radionuclides in the fracture. Sorption onto rock matrix, fracture surface and sorption into mobile and immobile colloids are included. The effect of colloidal particle size was also considered. Mass partition mechanisms between the colloids and solid matrix and between colloid and contaminant are represented by local equilibrium. In the three-phase i.e., retardation coefficient, hydrodynamic dispersion system, the coefficient, and fracture width are modified to include the equilibrium distribution coefficient of contaminant with a carrier. In the three phase model, much smaller retardation and hydrodynamic dispersion coefficients are obtained and the effect of fracture width is larger. With the additional consideration of colloidal particle sizes, these effects become ever larger. Numerical solutions for the model were obtained using a fully implicit finite difference scheme. A significant sensitivity to model parameters was discovered, and in particular, the equilibrium distribution coefficients between a contaminant and the carrier were found to be the most important factors.
Baek, Inseok
Anisotropic yielding of rocks at high temperatures and pressures
Results to date are: All of the starting materials for the three year project have been collected. Included in our collection are relatively fine-grained, fresh, oriented blocks of schist, gneiss, and micaceous quartzite with well-defined foliations and lineations as well as granite blocks oriented with respect to the principal quarrying orientations, the rift, grain, and hardway. A suite of samples has also been collected from an exposed granite stock and surrounding country rocks in order to evaluate the strengths and distribution of fabrics which may be encountered while drilling. These fabrics appear to be directly related to the forceful emplacement of the pluton. The literature on the mechanics of intrusion has been reviewed with regard to strain gradients and foliation development associated with diapiric flow. This information will be used to evaluate flow of varying fabrics on yield criteria within and surrounding magma chambers. Twenty-three successful experiments have been performed on samples of gneiss cored along six different orientations at temperatures ranging from 25{degrees} to 700{degrees}C. These experiments include extension tests, unconfined compression tests, and compression tests performed at P{sub c} = 100 MPa. Theoretical yield conditions for anisotropic materials have been reviewed and the assumptions upon which they are based probed. These yield conditions will ultimately be used to fit our data on gneiss, and the other foliated rocks under investigation. Two abstracts have been published and oral presentations made at the 1987 Fall Meeting of the American Geophysical Union, based upon our previous DOE-sponsored work on tensile fracturing of quartzite and related work on semi-brittle deformation of granitic rocks. 21 refs., 12 figs., 2 tabs.
Kronenberg, A.K.; Russell, J.E.; Handin, J.; Gottschalk, R.R.; Shea, W.T.
Analysis of the single-fiber-composite test to measure the mechanical properties of metal-ceramic interfaces
Tensile stress-strain curves for a metal-ceramic single fiber composite show load drops associated with every fiber break. Each curve exhibits a limited number of load drops that are characteristic of the level of the fiber-matrix bonding. A detailed analysis of these stress-strain curves gives the following results: (a) the magnitude of the load drops depends not only on the fiber strength but also on the work-hardening behavior of the metal matrix and the length of the shear relaxation zone at the interface; (b) the distribution of the magnitude of the load drops is determined by the random truncation of the shear relaxation length as part of the fiber fragmentation process; (c) the first load drop can be systematically used to determine the in situ Weibull strength statistics and a scaling law for the ceramic fiber; (d) the slope of the reloading portion immediately after a load drop is proportional to the fundamental work-hardening rate of the metal; (e) the interfacial (yield) shear strength of the metal-ceramic interface is described in terms of the total number of load drops and the magnitude of the first load drop. These results are applied to the case of copper-sapphire and copper-niobium-sapphire interfaces. An interlayer of niobium, approx. 30 nm thick, increases the interfacial shear strength by a factor of two. The interfacial shear strengths determined in the present study are lower by an order of magnitude compared to the values obtained with the thin film multiple cracking technique. This difference is explained by different mechanisms of shear relaxation at the interface after fracture of the ceramic phase.
Houpert, J.L.; Phoenix, S.L.; Raj, R. (Cornell Univ., Ithaca, NY (United States))
Anisotropic yielding of rocks at high temperatures and pressures; Annual Progress Report, 1988-1989
The experimental results we have obtained on Four-Mile gneiss have demonstrated that the yield behavior of quartzo-feldspathic rocks containing only a small percentage (10%) of mica can be markedly anisotropic, provided the mica minerals exhibit a strong crystallographic preferred orientation. Samples of gneiss oriented such that resolved shear stresses on the foliation plane are large are considerably weaker than granites of similar grain size and composition, and this weakness is attributed to enhanced nucleation of microcracks in quartz and feldspar adjacent to mica grains that are suitably oriented for slip. We expect the yield behavior of rocks containing a higher proportion of phyllosilicates to be influenced by the strongly anisotropic nature of these minerals as well, although the strengths, temperature and pressure dependencies, and flow-controlling mechanisms in such rocks may be significantly different.
Kronenberg, A.K.; Russell, J.E.; Carter, N.L.
PDC Bit Testing at Sandia Reveals Influence of Chatter in Hard-Rock Drilling
Polycrystalline diamond compact (PDC) bits have yet to be routinely applied to drilling the hard-rock formations characteristic of geothermal reservoirs. Most geothermal production wells are currently drilled with tungsten-carbide-insert roller-cone bits. PDC bits have significantly improved penetration rates and bit life beyond roller-cone bits in the oil and gas industry where soft to medium-hard rock types are encountered. If PDC bits could be used to double current penetration rates in hard rock geothermal well-drilling costs could be reduced by 15 percent or more. PDC bits exhibit reasonable life in hard-rock wear testing using the relatively rigid setups typical of laboratory testing. Unfortunately, field experience indicates otherwise. The prevailing mode of failure encountered by PDC bits returning from hard-rock formations in the field is catastrophic, presumably due to impact loading. These failures usually occur in advance of any appreciable wear that might dictate cutter replacement. Self-induced bit vibration, or ''chatter'', is one of the mechanisms that may be responsible for impact damage to PDC cutters in hard-rock drilling. Chatter is more severe in hard-rock formations since they induce significant dynamic loading on the cutter elements. Chatter is a phenomenon whereby the drillstring becomes dynamically unstable and excessive sustained vibrations occur. Unlike forced vibration, the force (i.e., weight on bit) that drives self-induced vibration is coupled with the response it produces. Many of the chatter principles derived in the machine tool industry are applicable to drilling. It is a simple matter to make changes to a machine tool to study the chatter phenomenon. This is not the case with drilling. Chatter occurs in field drilling due to the flexibility of the drillstring. Hence, laboratory setups must be made compliant to observe chatter.
HEFF---A user`s manual and guide for the HEFF code for thermal-mechanical analysis using the boundary-element method; Version 4.1: Yucca Mountain Site Characterization Project
The HEFF Code combines a simple boundary-element method of stress analysis with the closed form solutions for constant or exponentially decaying heat sources in an infinite elastic body to obtain an approximate method for analysis of underground excavations in a rock mass with heat generation. This manual describes the theoretical basis for the code, the code structure, model preparation, and step taken to assure that the code correctly performs its intended functions. The material contained within the report addresses the Software Quality Assurance Requirements for the Yucca Mountain Site Characterization Project. 13 refs., 26 figs., 14 tabs.
St. John, C.M.; Sanjeevan, K. [Agapito (J.F.T.) and Associates, Inc., Grand Junction, CO (United States)
Summary - Hot Dry Rock R&D Strategies and Applications
In geothermal energy technology, the hydrothermal systems rely on volcanic hot rocks being fortuitously co-located with an adequate supply of natural ground water, usually at some considerable depth within the earth. This represents essentially two accidents in the same place, and the occurrence is relatively rare. Yellowstone Park and the desert valley of southern California are the most noteworthy US. examples. Since the heat is the energy needed, if we could just get the water down to it and back. Well, that's what is being done with the hot dry rock program. A well is drilled down to where there is adequate heat in the rocks. The well is then pressurized until the rock fractures creating what amounts to a reservoir full of hot, shattered rock. Finally, a well is drilled into the reservoir and water is pumped in one well, heated by the rock, and taken out through the other well at useful temperatures and pressures. We are getting ready to run significant long-term flow tests at the Fenton Hill Hot Dry Rock site west of Los Alamos, New Mexico. We expect the operational information to provide the data to forecast the energy life of the wells as a production facility. This kind of resource is much more common than regular geothermal resources. Robert H. Hendron described the Long Term Flow Test and reservoir studies for which the project is preparing. A shortfall of available funding has slowed preparations, delaying the start of that test. The test is planning to gather data for more definitive reservoir modeling with energy availability or reservoir lifetime of primary interest. Other interests include geochemistry and tracer studies, microseismic response, water requirements and flow impedance which relates directly to the pumping power required. Progress has been made in modeling studies, chemically reactive tracer techniques, and in improvements in acoustic or microseismic event analysis. Donald W. Brown discussed reservoir modeling as it relates to production management of the HDR well. For wells which are fracture dominated rather than matrix-permeability controlled, a knowledge of the pressure-dependent permeability of the interconnected system of natural joints (or pre-existing fractures is critical to long-term power production from the wells) through optimized pressure management. It was mentioned that a knowledge of the pressure-dependent joint permeability could aid in designing more appropriate secondary recovery strategies in petroleum reservoirs, or reinjection I procedures of geothermal reservoirs. Dr. Bruce A. Robinson discussed the development of fluid flow and transport models for simulation of HDR geothermal reservoirs. These models are also expected to provide accurate predictions of long-term behavior and help in the development of strategies for reservoir improvement and operation. Two approaches were discussed. The discrete fracture approach is based on a random fracture network subject to prescribed statistical properties of the fracture set. It is used to simulate steady state fluid flow and solute transport. The other approach used the continuum approximation. This type of model is appropriate when the reservoir consists of many interconnected fractures, as is the case at Fenton Hill.
Tennyson, George P..
The oil and gas potential of southern Bolivia: Contributions from a dual source rock system
The southern Sub-Andean and Chaco basins of Bolivia produce oil, gas and condensate from reservoirs ranging from Devonian to Tertiary in age. Geochemical evidence points to contributions from two Paleozoic source rocks: the Devonian Los Monos Formation and the Silurian Kirusillas Formation. Rock-Eval pyrolysis, biomarker data, microscopic kerogen analysis, and burial history modeling are used to assess the quality, distribution, and maturity of both source rock systems. The geochemical results are then integrated with the structural model for the area in order to determine the most likely pathways for migration of oil and gas in the thrust belt and its foreland. Geochemical analysis and modeling show that the primary source rock, shales of the Devonian Los Monos Formation, entered the oil window during the initial phase of thrusting in the sub-Andean belt. This provides ideal timing for oil accumulation in younger reservoirs of the thrust belt. The secondary source rock, although richer, consumed most of its oil generating capacity prior to the development of the thrust related structures. Depending on burial depth and location, however, the Silurian source still contributes gas, and some oil, to traps in the region.
Hartshorn, K.G. [Chevron Petroleum Company of Colombia, Santafe de Bogota (Colombia)
Micromachined low frequency rocking accelerometer with capacitive pickoff
A micro electro mechanical sensor that uses capacitive readout electronics. The sensor involves a micromachined low frequency rocking accelerometer with capacitive pickoff fabricated by deep reactive ion etching. The accelerometer includes a central silicon proof mass, is suspended by a thin polysilicon tether, and has a moving electrode (capacitor plate or interdigitated fingers) located at each end the proof mass. During movement (acceleration), the tethered mass moves relative to the surrounding packaging, for example, and this defection is measured capacitively by a plate capacitor or interdigitated finger capacitor, having the cooperating fixed electrode (capacitor plate or interdigitated fingers) positioned on the packaging, for example. The micromachined rocking accelerometer has a low frequency (<500 Hz), high sensitivity (.mu.G), with minimal power usage. The capacitors are connected to a power supply (battery) and to sensor interface electronics, which may include an analog to digital (A/D) converter, logic, RF communication link, antenna, etc. The sensor (accelerometer) may be, for example, packaged along with the interface electronics and a communication system in a 2".times.2".times.2" cube. The proof mass may be asymmetric or symmetric. Additional actuating capacitive plates may be used for feedback control which gives a greater dynamic range.
Lee, Abraham P. (Arlington, VA); Simon, Jonathon N. (San Leandro, CA); McConaghy, Charles F. (Livermore, CA)
Use of explosives in deep rock mining: in situ energy and mineral recovery
Chemical explosives may become a key element in many of the in situ energy and mineral recovery methods under development. The potential role of explosives in deep rock mining for resource recovery is discussed. Several energy and mineral recovery programs described are an outgrowth of the Plowshare Program and Explosives R and D conducted as part of the AEC/ERDA mission at Lawrence Livermore Laboratory. Several important aspects of the use of explosives in deep rock mining are reviewed. First, the status of knowledge of deep rock fracturing to create permeability underground is discussed. Completely contained blasting has not been a widely applied tool used in the mining industry. It is concluded that data available on deep rock fracture is minimal and that the mechanisms that control the processes must be understood before technical and economic feasibility can be established. The unusual problems in the selection of an explosive or blasting agent for deep rock applications including emphasis on the functioning at depth and safety aspects are also discussed. Finally, a brief review of similar activities within the U.S. is given.
Finger, M.; Larson, D.
Rim Rock Wind Farm | Open Energy Information
Rim Rock Wind Farm Rim Rock Wind Farm Jump to: navigation, search Name Rim Rock Wind Farm Facility Rim Rock Wind Farm Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner NaturEner Developer NaturEner Energy Purchaser San Diego Gas & Electric Location Glacier and Toole Counties MT Coordinates 48.779564°, -112.061291° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":48.779564,"lon":-112.061291,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Hot-dry-rock geothermal resource 1980
The work performed on hot dry rock (HDR) geothermal resource evaluation, site characterization, and geophysical exploration techniques is summarized. The work was done by region (Far West, Pacific Northwest, Southwest, Rocky Mountain States, Midcontinent, and Eastern) and limited to the conterminous US.
Heiken, G.; Goff, F.; Cremer, G. (ed.)
Storage capacity in hot dry rock reservoirs
A method is described for extracting thermal energy, in a cyclic manner, from geologic strata which may be termed hot dry rock. A reservoir comprised of hot fractured rock is established and water or other liquid is passed through the reservoir. The water is heated by the hot rock, recovered from the reservoir, cooled by extraction of heat by means of heat exchange apparatus on the surface, and then re-injected into the reservoir to be heated again. Water is added to the reservoir by means of an injection well and recovered from the reservoir by means of a production well. Water is continuously provided to the reservoir and continuously withdrawn from the reservoir at two different flow rates, a base rate and a peak rate. Increasing water flow from the base rate to the peak rate is accomplished by rapidly decreasing backpressure at the outlet of the production well in order to meet periodic needs for amounts of thermal energy greater than a baseload amount, such as to generate additional electric power to meet peak demands. The rate of flow of water provided to the hot dry rock reservoir is maintained at a value effective to prevent depletion of the liquid inventory of the reservoir. 4 figs.
Brown, D.W.
Segmentation of cracks in shale rock
In this paper the use of morphological connected filters are studied for segmenting sheet- and thread-like cracks in images of shale rock. A volume formed from a stack of 2-D X-ray images is processed using 3-D attributes. The shape-preserving property ...
Erik R. Urbach; Marina Pervukhina; Leanne Bischof
TABLE OF CONTENTS A: Rock Physics and Geology. Pressure-solution models and the velocity......................................................... A3 Pressure trends of compressional-and shear-wave velocities measured measured in sands to 20 MPA.....................................................C3 Properties of pore fluids at very high pressures from equations of state. Walls & Dvorkin
Nur, Amos
A method of extracting thermal energy, in a cyclic manner, from geologic strata which may be termed hot dry rock. A reservoir comprised of hot fractured rock is established and water or other liquid is passed through the reservoir. The water is heated by the hot rock, recovered from the reservoir, cooled by extraction of heat by means of heat exchange apparatus on the surface, and then re-injected into the reservoir to be heated again. Water is added to the reservoir by means of an injection well and recovered from the reservoir by means of a production well. Water is continuously provided to the reservoir and continuously withdrawn from the reservoir at two different flow rates, a base rate and a peak rate. Increasing water flow from the base rate to the peak rate is accomplished by rapidly decreasing backpressure at the outlet of the production well in order to meet periodic needs for amounts of thermal energy greater than a baseload amount, such as to generate additional electric power to meet peak demands. The rate of flow of water provided to the hot dry rock reservoir is maintained at a value effective to prevent depletion of the liquid
Brown, Donald W. (Los Alamos, NM)
Transfer of hot dry rock technology
The Hot Dry Rock Geothermal Energy Development Program has focused worldwide attention on the facts that natural heat in the upper part of the earth's crust is an essentially inexhaustible energy resource which is accessible almost everywhere, and that practical means now exist to extract useful heat from the hot rock and bring it to the earth's surface for beneficial use. The Hot Dry Rock Program has successfully constructed and operated a prototype hot, dry rock energy system that produced heat at the temperatures and rates required for large-scale space heating and many other direct uses of heat. The Program is now in the final stages of constructing a larger, hotter system potentially capable of satisfying the energy requirements of a small, commercial, electrical-generating power plant. To create and understand the behavior of such system, it has been necessary to develop or support the development of a wide variety of equipment, instruments, techniques, and analyses. Much of this innovative technology has already been transferred to the private sector and to other research and development programs, and more is continuously being made available as its usefulness is demonstrated. This report describes some of these developments and indicates where this new technology is being used or can be useful to industry, engineering, and science.
Chemically- and mechanically-mediated influences on the transport and mechanical characteristics of rock fractures
reduction of the thermal stress upon cooling. When thereduction of thermal stress upon cooling compared with thein stress upon cooling. The thermal stress generated is
Min, K.-B.
Porosity and surface area evolution during weathering of two igneous rocks
During weathering, rocks release nutrients and storewater vital for growth ofmicrobial and plant life. Thus, the growth of porosity as weathering advances into bedrock is a life-sustaining process for terrestrial ecosystems. Here, we use small-angle and ultra small-angle neutron scattering to show how porosity develops during initial weathering under tropical conditions of two igneous rock compositions, basaltic andesite and quartz diorite. The quartz diorite weathers spheroidally while the basaltic andesite does not. The weathering advance rates of the two systems also differ, perhaps due to this difference in mechanism, from 0.24 to 100 mm kyr1, respectively. The scattering data document how surfaces inside the feldspar-dominated rocks change as weathering advances into the protolith. In the unaltered rocks, neutrons scatter fromtwo types of featureswhose dimensions vary from6 nmto 40 lm: pores and bumps on pore grain surfaces. These features result in scattering data for both unaltered rocks that document multi-fractal behavior: scattering is best described by amass fractal dimension (Dm) and a surface fractal dimension (Ds) for features of length scales greater than and less than 1 lm, respectively. In the basaltic andesite, Dm is approximately 2.9 and Ds is approximately 2.7. The mechanism of solute transport during weathering of this rock is diffusion. Porosity and surface area increase from 1.5%to 8.5%and 3 to 23 m2 g1 respectively in a relatively consistent trend across themm-thick plagioclase reaction front. Across this front, both fractal dimensions decrease, consistentwith development of amoremonodisperse pore networkwith smoother pore surfaces. Both changes are consistent largely with increasing connectivity of pores without significant surface roughening, as expected for transport-limited weathering. In contrast, porosity and surface area increase from 1.3% to 9.5% and 1.5 to 13 m2 g1 respectively across a many cm-thick reaction front in the spheroidally weathering quartz diorite. In that rock, Dm is approximately 2.8 andDs is approximately 2.5 prior to weathering. These two fractals transform during weathering to multiple surface fractals as micro-cracking reduces the size of diffusion-limited subzones of thematrix.Across the reaction front of plagioclase in the quartz diorite, the specific surface area and porosity change very little until the pointwhere the rock disaggregates into saprolite. The different patterns in porosity development of the two rocks are attributed to advective infiltration plus diffusion in the rock that spheroidally fractures versus diffusion-only in the rock that does not. Fracturing apparently diminishes the size of the diffusion-limited parts of the spheroidally weathering rock system to promote infiltration of meteoric fluids, thereforeexplaining the faster weathering advance rate into that rock.
Navarre-Sitchler, Alexis [Colorado School of Mines, Golden; Cole, David [Ohio State University; Rother, Gernot [ORNL; Jin, Lixin [University of Texas, El Paso; Buss, Heather [University of Bristol, UK; Brantley, S. L. [Pennsylvania State University, University Park, PA
Analysis of mechanisms of carrier emission in the p-i-n structures with In(Ga)As quantum dots
With the help of the photocurrent spectroscopy, the mechanism of emission of charge carriers from energy levels of the (In,Ga)As/(Al,Ga)As quantum dots of different design are studied. Thermal activation is shown to be the main mechanism of carrier emission from the quantum dots for the isolated layer of quantum dots separated by wide (Al,Ga)As spacer layers. At a small width of the (Al,Ga)As spacer layer, when electron binding of separate layers of the quantum dots in the vertical direction takes place, the role of the tunneling mechanism of carrier emission between the vertically coupled quantum dots increases.
Shatalina, E. S., E-mail: firstname.lastname@example.com; Blokhin, S. A.; Nadtochy, A. M.; Payusov, A. S.; Savelyev, A. V.; Maximov, M. V.; Zhukov, A. E. [St. Petersburg Academic University, Nanotechnology Research and Education Centre (Russian Federation); Ledentsov, N. N. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation); Kovsh, A. R.; Mikhrin, S. S.; Ustinov, V. M. [Innolume GmbH (Germany)
Esimation of field-scale thermal conductivities of unsaturated rocks from in-situ temperature data
vicinity of the heat source, and rock temperature exceededand the dry rock near the heat source. The other differencesources, heat transfer takes place through the wet rock (see
Mukhopadhyay, Sumit; Tsang, Yvonne W.; Birkholzer, Jens T.
Index Appendix 1. Sources of Information Rock properties -various sources, and list of mines in crystalline rock whichoz SOURCE EOLOGY INFORMATION MINERALOGY OF HOST ROCKS GULF
Wallenberg, H.A.
Proceedings of the Second International Symposium on Dynamics of Fluids in Fractured Rock
toward the heat source, or into the rock underlying the heatcharacterizing DNAPL source zones in fractured rock at theby a point source injection in fractured rock with multiple
Faybishenko, Boris; Witherspoon, Paul A.
The second skin approach : skin strain field analysis and mechanical counter pressure prototyping for advanced spacesuit design
The primary aim of this thesis is to advance the theory of advanced locomotion mechanical counter pressure (MCP) spacesuits by studying the changes in the human body shape during joint motion. Two experiments take advantage ...
Bethke, Kristen (Kristen Ann)
Little Rock, Arkansas Small Business IT Security Workshop
... Twitter, Facebook & Blogs Free Workshop helps Small Business Owners Reduce Cyber Threats LITTLE ROCK--The US ...
A digital rock density map of New Zealand
Digital geological maps of New Zealand (QMAP) are combined with 9256 samples with rock density measurements from the national rock catalogue PETLAB and supplementary geological sources to generate a first digital density model of New Zealand. This digital ... Keywords: Crust, Database, Density, Geological mapping, Gravimetry, Rock types
Robert Tenzer; Pascal Sirguey; Mark Rattenbury; Julia Nicolson
Simulation of water-rock interaction in the Yellowstone geothermal system using TOUGHREACT
The Yellowstone geothermal system provides an ideal opportunity to test the ability of reactive transport models to simulate the chemical and hydrological effects of water-rock interaction. Previous studies of the Yellowstone geothermal system have characterized water-rock interaction through analysis of rocks and fluids obtained from both surface and downhole samples. Fluid chemistry, rock mineralogy, permeability, porosity, and thermal data obtained from the Y-8 borehole in Upper Geyser Basin were used to constrain a series of reactive transport simulations of the Yellowstone geothermal system using TOUGHREACT. Three distinct stratigraphic units were encountered in the 153.4 m deep Y-8 drill core: volcaniclastic sandstone, perlitic rhyolitic lava, and nonwelded pumiceous tuff. The main alteration phases identified in the Y-8 core samples include clay minerals, zeolites, silica polymorphs, adularia, and calcite. Temperatures observed in the Y-8 borehole increase with depth from sub-boiling conditions at the surface to a maximum of 169.8 C at a depth of 104.1 m, with near-isothermal conditions persisting down to the well bottom. 1-D models of the Y-8 core hole were constructed to simulate the observed alteration mineral assemblage given the initial rock mineralogy and observed fluid chemistry and temperatures. Preliminary simulations involving the perlitic rhyolitic lava unit are consistent with the observed alteration of rhyolitic glass to form celadonite.
Dobson, Patrick F.; Salah, Sonia; Spycher, Nicolas; Sonnenthal, Eric L.
Simulation of water-rock interaction in the yellowstone geothermal system using TOUGHREACT
The Yellowstone geothermal system provides an ideal opportunity to test the ability of reactive transport models to accurately simulate water-rock interaction. Previous studies of the Yellowstone geothermal system have characterized water-rock interaction through analysis of rocks and fluids obtained from both surface and downhole samples. Fluid chemistry, rock mineralogy, permeability, porosity, and thermal data obtained from the Y-8 borehole in Upper Geyser Basin were used to constrain a series of reactive transport simulations of the Yellowstone geothermal system using TOUGHREACT. Three distinct stratigraphic units were encountered in the 153.4 m deep Y-8 drill core: volcaniclastic sandstone, perlitic rhyolitic lava, and nonwelded pumiceous tuff. The main alteration phases identified in the Y-8 core samples include clay minerals, zeolites, silica polymorphs, adularia, and calcite. Temperatures observed in the Y-8 borehole increase with depth from sub-boiling conditions at the surface to a maximum of 169.8 C at a depth of 104.1 m, with near-isothermal conditions persisting down to the well bottom. 1-D models of the Y-8 core hole were constructed to determine if TOUGHREACT could accurately predict the observed alteration mineral assemblage given the initial rock mineralogy and observed fluid chemistry and temperatures. Preliminary simulations involving the perlitic rhyolitic lava unit are consistent with the observed alteration of rhyolitic glass to form celadonite.
Dobson, P.F.; Salah, S.; Spycher, N.; Sonnenthal, E.
Rock River Wind Farm | Open Energy Information
Wind Farm Wind Farm Jump to: navigation, search Name Rock River Wind Farm Facility Rock River Wind Farm Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner Shell Wind Energy Developer SeaWest Energy Purchaser PacifiCorp Location Arlington and Carbon Counties WY Coordinates 41.6996°, -107.003° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":41.6996,"lon":-107.003,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Low Pore Connectivity in Natural Rock
As repositories for CO? and radioactive waste, as oil and gas reservoirs, and as contaminated sites needing remediation, rock formations play a central role in energy and environmental management. The connectivity of the rock's porespace strongly affects fluid flow and solute transport. This work examines pore connectivity and its implications for fluid flow and chemical transport. Three experimental approaches (imbibition, tracer concentration profiles, and imaging) were used in combination with network modeling. In the imbibition results, three types of imbibition slope [log (cumulative imbibition) vs. log (imbibition time)] were found: the classical 0.5, plus 0.26, and 0.26 transitioning to 0.5. The imbibition slope of 0.26 seen in Indiana sandstone, metagraywacke, and Barnett shale indicates low pore connectivity, in contrast to the slope of 0.5 seen in the well-connected Berea sandstone. In the tracer profile work, rocks exhibited different distances to the plateau porosity, consistent with the pore connectivity from the imbibition tests. Injection of a molten metal into connected pore spaces, followed by 2-D imaging of the solidified alloy in polished thin sections, allowed direct assessment of pore structure and lateral connection in the rock samples. Pore-scale network modeling gave results consistent with measurements, confirming pore connectivity as the underlying cause of both anomalous behaviors: imbibition slope not having the classical value of 0.5, and accessible porosity being a function of distance from the edge. A poorly connected porespace will exhibit anomalous behavior in fluid flow and chemical transport, such as a lower imbibition slope (in air�water system) and diffusion rate than expected from classical behavior.
Hu, Qinhong; Ewing, Robert P.; Dultz, Stefan
Dynamic rock fragmentation: oil shale applications
Explosive rock fragmentation techniques used in many resource recovery operations have in the past relied heavily upon traditions of field experience for their design. As these resources, notably energy resources, become less accessible, it becomes increasingly important that fragmentation techniques be optimized and that methods be developed to effectively evaluate new or modified explosive deployment schemes. Computational procedures have significant potential in these areas, but practical applications must be preceded by a thorough understanding of the rock fracture phenomenon and the development of physically sound computational models. This paper presents some of the important features of a rock fragmentation model that was developed as part of a program directed at the preparation of subterranean beds for in situ processing of oil shale. The model, which has been implemented in a two-dimensional Lagrangian wavecode, employs a continuum damage concept to quantify the degree of fracturing and takes into account experimental observations that fracture strength and fragment dimensions depend on tensile strain rates. The basic premises of the model are considered in the paper as well as some comparisons between calculated results and observations from blasting experiments.
Boade, R. R.; Grady, D. E.; Kipp, M. E.
Los Alamos hot dry rock geothermal project
The greatest potential for geothermal energy is the almost unlimited energy contained in the vast regions of hot, but essentially impermeable, rock within the first six or seven km of the Earth's crust. For the past five years, the Los Alamos Scientific Laboratory has been investigating and developing a practical, economical and environmentally acceptable method of extracting this energy. By early 1978, a 10 MW (thermal) heat extraction experiment will be in operation. In the Los Alamos concept, a man-made geothermal reservoir is formed by drilling into a region of suitably hot rock, and then creating within the rock a very large surface for heat transfer by large-scale hydraulic-fracturing techniques. After a circulation loop is formed by drilling a second hole to intersect the fractured region, the heat contained in this reservoir is brought to the surface by the buoyant closed-loop circulation of water. The water is kept liquid throughout the loop by pressurization, thereby increasing the rate of heat transport up the withdrawal hole compared to that possible with steam.
Brown, D.W.; Pettitt, R.A.
Development of hot dry rock resources
The LASL Hot Dry Rock Geothermal Energy Project is the only U.S. field test of this geothermal resource. In the LASL concept, a man-made geothermal reservoir would be formed by drilling a deep hole into relatively impermeable hot rock, creating a large surface area for heat transfer by fracturing the rock hydraulically, then drilling a second hole to intersect the fracture to complete the circulation loop. In 1974, the first hole was drilled to a depth of 2929 m (9610 ft) and a hydraulic fracture was produced near the bottom. In 1975, a second hole was directionally drilled to intersect the fracture. Although the desired intersection was not achieved, a connection was made through which water was circulated. After a year's study of the fracture system, drilling began again in April 1977 and an improved connection was achieved. In September of 1977 a 5 MW (thermal) heat extraction and circulation experiment was conducted for 100 h as a preliminary test of the concept. An 1800-h circulation experiment was concluded on April 13, 1978 to determine temperature-drawdown, permeation water loss and flow characteristics of the pressurized reservoir, to examine chemistry changes in the circulating fluid, and to monitor for induced seismic effects.
Pettitt, R.A.; Tester, J.W.
Calculation of explosive rock breakage: oil shale
Improved efficiency in explosive rock breakage becomes increasingly important as mining costs and the need to tap underground resources continue to grow. Industry has recognized this need for many years and has done a great deal in developing new products and new blasting techniques, generally by purely empirical means. One particular application that has received added attention within the past several years, and one that lends itself to a more objective theoretical study, is explosive fracture of oil shale for conventional and in situ fossil energy recovery. Numerical calculation of oil shale fracturization with commercial explosives has the potential to add to an objective understanding of the breakage process. Often, in such numerical studies, only one or two parts of the total problem are addressed with any degree of sophistication or completeness. Here an attempt is made to treat the entire problem, i.e., explosive characterization, constitutive behavior of intact rock, and a mathematical description of rock fracture. The final results are two-dimensional calculations of explosively induced fracture damage in oil shale.
Johnson, J.N.
Artificial geothermal reservoirs in hot volcanic rock
S>Some recent results from the Los Alamos program in which hydraulic fracturing is used for the recovery of geothermal energy are discussed. The location is about 4 kilometers west and south of the ring fault of the enormous Jemez Caldera in the northcentral part of New Mexico. It is shown that geothermal energy may be extracted from hot rock that does not contain circulating hot water or steam and is relatively impermeable. A fluid is pumped at high pressure into an isolated section of a wellbore. If the well is cased the pipe in this pressurized region is perforated as it is in the petroleum industry, so that the pressure may be applied to the rock, cracking it. A second well is drilled a few hundred feet away from the first. Cold water is injected through the first pipe, circulates through the crack, and hot water returns to the surface through the second pipe. Results are described and circumstances are discussed under which artiflcial geothermal reservoirs might be created in the basaltic rock of Hawaii. (MCW)
Aamodt, R.L.
Hot Dry Rock Geothermal Energy Development Program
During Fiscal Year 1987, emphasis in the Hot Dry Rock Geothermal Energy Development Program was on preparations for a Long-Term Flow Test'' of the Phase II'' or Engineering'' hot dry rock energy system at Fenton Hill, New Mexico. A successful 30-day flow test of the system during FY86 indicated that such a system would produce heat at a temperature and rate that could support operation of a commercial electrical power plant. However, it did not answer certain questions basic to the economics of long-term operation, including the rate of depletion of the thermal reservoir, the rate of water loss from the system, and the possibility of operating problems during extended continuous operation. Preparations for a one-year flow test of the system to answer these and more fundamental questions concerning hot dry rock systems were made in FY87: design of the required surface facilities; procurement and installation of some of their components; development and testing of slimline logging tools for use through small-diameter production tubing; research on temperature-sensitive reactive chemical tracers to monitor thermal depletion of the reservoir; and computer simulations of the 30-day test, extended to modeling the planned Long-Term Flow Test. 45 refs., 34 figs., 5 tabs.
Smith, M.C.; Hendron, R.H.; Murphy, H.D.; Wilson, M.G.
Thermo-Mechanical Bending Testing and Analysis for Public Service Electric and Gas Company Field-Aged Cables
High-pressure fluid-filled, pipe-type cables have been in operation since the mid-1930s, and they are acknowledged to be very reliable. However, some 230-kV and 345-kV cables, primarily those installed in the 1960s and 1970s, have experienced a failure mechanism known as thermo-mechanical bending (TMB). Cable expansion with an increase in loading causes the cables to form a series of bends. The cables tend to straighten as they cool when loads are reduced. In most cases, this movement can occur daily for...
Strength and ductility of four dry igneous rocks at low pressures and temperatures to partial melting
Energy extraction from magma requires stable boreholes at relatively shallow depths (< 10 km) in rocks at temperatures of the order of 1000/sup 0/C. Accordingly, the failure strengths, strains at failure, and associated deformation mechanisms of room-dry andesite, besalt, granodiorite, and obsidian are determined at temperatures to partial melting (> 1050/sup 0/C), at confining pressures of 0 and 50 MPa, and strain rate of 10/sup -4//s. The strength reductions of the crystalline rocks are more or less linear until they steepen suddenly with approach to melting. When that occurs, strengths vanish and deformations become quasiviscous. The obsidian is stronger than the crystalline rocks to 600/sup 0/C where glass softening begins and strength goes to zero at 800/sup 0/C. All rocks are brittle throughout the entire temperature range until melting or softening occurs. Shortenings at failure are 3 percent or less. The crystalline rocks tend to deform primarily by precursive microscopic extension fracturing and its coalescence into macroscopic faults. The abundance of load-induced fractures remains about constant, but thermal cracking increases with increasing temperature. Results from tests at 25/sup 0/C on specimens that previously had been heated to 900-1000/sup 0/C clearly show that the weakening of unconfined specimens is due to the thermal cracking. Weakening of confined specimens, however, probably is due to an inherent temperature effect on the load-induced fracturing process. Comparisons of instantaneous failure-strengths with stresses likely ot occur at the walls of boreholes show that a hole as deep as 10 km in impermeable crystalline rock is not likely to fail under short-time loading even at 1000/sup 0/C, unless the maximum in-situ horizontal stress is greater than or equal to vetical stress and the hole is open (i.e., borehole pressure is zero). 27 refs., 10 figs., 7 tabs.
Friedman, M.; Handin, J.; Higgs, N.G.; Lantz, J.R.
Rapid excavation by rock melting. LASL subterrene program, December 31, 1972--September 1, 1973
Research is continuing on establishing the technical and economic feasibility of excavation systems based upon the rockmelting (Subterrene) concept. A series of electrically powered, small-diameter prototype melting penetrators have been developed and tested. Research activities include optimizing penetrator configurations, designing high-performance heater systems, and improving refractory-metals technology. The properties of the glass linings that are automatically formed on the melted holes are being investigated for a wide variety of rocks and soils. Thermal and fluid-mechanics analyses of the melt flows are being conducted with the objective of optimizing penetraton designs. Initial economic models of the rock-melting concept extended to large tunnelers are being developed. Field tests and demonstrations of the prototype devices continue to be performed in a wide range of rock and soil types. The conceptual design of the electrically powered, self-propelled, remotely guided, horizontal tunnel-alignment prospecting system (Geoprospector) has been initiated. Such a device will also find applications in energy transmission, i.e., utility and pipeline installations. The long-term goal of the research is to develop the technology and prototype hardware that will ultimately lead to large tunneling devices, with improved advance rates and reduced tunnel project costs. The rockmelting concept includes elements that will result in innovative solutions to the three major functional areas of tunneling: rock disintegration, materials handling, and hole-support linings. The proposed excavation method, which is relatively insensitive to variations in rock formation, produces a liquid melt that can be chilled to a glass and formed into a dense, strong, firmly attached hole lining. Unique applications to large automated tunneling systems, ultradeep coring for geoscience research, and hot-rock penetration for geothermal energy development are being investigated, (auth)
Hanold, R.J.
HDR (Hot Dry Rock) technology transfer activities in the Clear Lake Area, California
A large Hot Dry Rock resource has been recognized in northern California. It underlies the region extending NE of The Geysers to N of the City of Clearlake. The long-range productive potential is thousands of megawatts. The geothermal resource is heterogeneous. There are two mechanisms of heat flow occurring together. One is fluid transport, up natural zones of permeability, to outflows as surface springs. The other is conductive heat flow through impermeable rock. The temperature isotherms are thought to be nearly level surfaces, for example, the 300{degree}C isotherm is at about 8000 ft depth, with spikes'' or ridges'' occurring around narrow zones of fluid flow. While there is accessible heat at shallow depth in the naturally permeable rocks, the really substantial resource is in the impermeable rock. This is the HDR resource. The potential reservoir rocks are Franciscan greywackes and greenstones. Recorded drilling problems appear to be mainly due to intersection with serpentinites or to the effects of stimulation, so are potentially avoidable. Greywacke is favoured as a reservoir rock, and is expected to fail by brittle fracture. The water shortages in Northern California appear to be surmountable. Leakoff rates are expected to be low. Sewerage water may be available for fill and makeup. There is a possibility of combining HDR heat power production with sewerage disposal. To establish the first HDR producer in Northern California offers challenges in technology transfer. Two significant challenges will be creation of dispersed permeability in a greywacke reservoir, and pressure management in the vicinity of naturally permeable zones. A successful demonstration of HDR production technology will improve the long-term prospects for the geothermal power industry in California. 29 refs., 20 figs., 4 tabs.
Burns, K.; Potter, R.
Experimentally determined rock-fluid interactions applicable to a natural hot-dry-rock geothermal system
The field program cnsists of experiments in which hot rock of low permeability is hydraulically fractured between two wellbores. Water is circulated from one well to the other through the fractured hot rock. Our field experiments are designed to test reservoir engineering parameters such as heat-extraction rates, water-loss rates, flow characteristics including impedance and buoyancy, seismic activity, and fluid chemistry. Laboratory experiments were designed to provide information on the mineral-water reactivity encountered during the field program. Two experimental circulation systems tested the rates of dissolution and alteration during dynamic flow. Solubility of rock in agitated systems was studied. Moreover, pure minerals, samples of the granodiorite from the actual reservoir, and Tijeras Canyon granite have been reacted with distilled water and various solutions of NaCl, NaOH, and Na/sub 2/CO/sub 3/. The results of these experimental systems are compared to the observations made in field experiments done within the hot dry rock reservoir at a depth of approximately 3 km where the initial rock temperature was 150 to 200/sup 0/C.
Charles, R.W.; Grigsby, C.O.; Holley, C.E. Jr.; Tester, J.W.; Blatz, L.A.
Goa, India Permeability of Charnokite Rock at High Temperatures
ABSTRACT: Permeability at high temperature is a very important parameter to be considered for designing underground high level nuclear waste repository (HLW) in rock mass. The surrounding rock mass is exposed to heat radiated by HLW when it is buried underground and development or extension of micro-cracks takes place in the host rock due to rise in temperature. Keeping this in view, the permeability study was conducted for Charnokite rock at high temperatures in the range from room temperature, 30 to 200 o C. The cylindrical rock samples of 36mm diameter and 150mm in length were used as per the required size for the equipment permeameter, TEMCO, USA. Total thirty rock samples were tested at various temperatures using nitrogen gas as fluid. The permeability tests were conducted at confining pressure of around 4MPa in order to simulate the horizontal in situ stress conditions in Charnokite rock at the depth of 400m for construction of HLW repository. 1
R. D. Dwivedi; R. K. Goel; A. Swarup; V. V. R. Prasad; R. K. Bajpai; P. K. Narayan; V. Arumugam
Hot-dry-rock geothermal-energy development program. Annual report, fiscal year 1981
During fiscal year 1981, activities of the Hot Dry Rock Geothermal Energy Development Program were concentrated in four principal areas: (1) data collection to permit improved estimates of the hot dry rock geothermal energy resource base of various regions of the United States and of the United States as a whole, combined with detailed investigations of several areas that appear particularly promising either for further energy extraction experiments or for future commercial development; (2) successful completion of a 9-month, continuous, closed-loop, recirculating flow test in the enlarged Phase I System at Fenton Hill, New Mexico - a pressurized-water heat-extraction loop developed in low-permeability granitic rock by hydraulic fracturing; (3) successful completion at a depth of 4084 m (13,933 ft) of well EE-3, the production well of a larger, deeper, and hotter, Phase II System at Fenton Hill. Well EE-3 was directionally drilled with control of both azimuth and inclination. Its inclined section is about 380 m (1250 ft) vertically above the injection well, EE-2, which was completed in FY80; and (4) supporting activities included new developments in downhole instrumentation and equipment, geochemical and geophysical studies, rock-mechanics and fluid-mechanics investigations, computer analyses and modeling, and overall system design. Under an International Energy Agency agreement, the New Energy Development Organization, representing the Government of Japan has joined Kernforschungsanlage-Juelich GmbH, representing the Federal Republic of Germany, and the US Department of Energy as an active participant in the Fenton Hill Hot Dry Rock Project.
Smith, M.C.; Ponder, G.M. (comps.)
Organic matter characteristics of CenomanianTuronian source rocks: implications for petroleum and gas
and shale source rocks . In: Petroleum Geochemistry and Source Rock Potential of Carbonate Rocks (Ed. by G of petroleum . In: Petroleum Geochemistry and Source Rock Potential of Carbonate Rocks (Ed. by G. Palacas of petroleum in Mesozoic reservoirs to carbonate source rocks of Jurassic Smackover Formation, southwestern
Paris-Sud XI, Université de
Analysis of the working process and mechanical losses in a Stirling engine for a solar power unit
In this paper a second level mathematical model for the computational simulation of the working process of a 1-kW Stirling engine has been used and the results obtained are presented. The internal circuit of the engine in the calculation scheme was divided into five chambers, namely, the expansion space, heater, regenerator, cooler and the compression space, and the governing system of ordinary differential equations for the energy and mass conservation were solved in each chamber by Euler`s method. In addition, mechanical losses in the construction of the engine have been determined and the computational results show that the mechanical losses for this particular design of the Stirling engine may be up to 50% of the indicated power of the engine.
Makhkamov, K.K. [Uzbek Academy of Sciences, Tashkent (Uzbekistan). Physical and Technical Inst.; Ingham, D.B. [Univ. of Leeds (United Kingdom). Dept. of Applied Mathematics
Fracture and Healing of Rock Salt Related to Salt Caverns
In recent years, serious investigations of potential extension of the useful life of older caverns or of the use of abandoned caverns for waste disposal have been of interest to the technical community. All of the potential applications depend upon understanding the reamer in which older caverns and sealing systems can fail. Such an understanding will require a more detailed knowledge of the fracture of salt than has been necessary to date. Fortunately, the knowledge of the fracture and healing of salt has made significant advances in the last decade, and is in a position to yield meaningful insights to older cavern behavior. In particular, micromechanical mechanisms of fracture and the concept of a fracture mechanism map have been essential guides, as has the utilization of continuum damage mechanics. The Multimechanism Deformation Coupled Fracture (MDCF) model, which is summarized extensively in this work was developed specifically to treat both the creep and fracture of salt, and was later extended to incorporate the fracture healing process known to occur in rock salt. Fracture in salt is based on the formation and evolution of microfractures, which may take the form of wing tip cracks, either in the body or the boundary of the grain. This type of crack deforms under shear to produce a strain, and furthermore, the opening of the wing cracks produce volume strain or dilatancy. In the presence of a confining pressure, microcrack formation may be suppressed, as is often the case for triaxial compression tests or natural underground stress situations. However, if the confining pressure is insufficient to suppress fracture, then the fractures will evolve with time to give the characteristic tertiary creep response. Two first order kinetics processes, closure of cracks and healing of cracks, control the healing process. Significantly, volume strain produced by microfractures may lead to changes in the permeability of the salt, which can become a major concern in cavern sealing and operation. The MDCF model is used in three simulations of field experiments in which indirect measures were obtained of the generation of damage. The results of the simulations help to verify the model and suggest that the model captures the correct fracture behavior of rock salt. The model is used in this work to estimate the generation and location of damage around a cylindrical storage cavern. The results are interesting because stress conditions around the cylindrical cavern do not lead to large amounts of damage. Moreover, the damage is such that general failure can not readily occur, nor does the extent of the damage suggest possible increased permeation when the surrounding salt is impermeable.
Chan, K.S.; Fossum, A.F.; Munson, D.E.
An evaluation of near-field host rock temperatures for a spent fuel repository
A repository heat transfer analysis has been performed by the Pacific Northwest Laboratory (PNL) for the US Department of Energy's Performance Assessment Scientific Support Program. The objective of this study was to evaluate the near-field thermal environmental conditions for a spent fuel repository system. A spent fuel logistics analysis was performed using a waste management system simulation model, WASTES-II, to evaluate the thermal characteristics of spent fuel received at the repository. A repository-scale thermal analysis was performed using a finite difference heat transfer code, TEMPEST, to evaluate the near-field host rock temperature. The calculated temporal and spatial distributions of near-field host rock temperatures provide input to the repository source term model in evaluations of engineered barrier system performance. 9 refs., 10 figs., 2 tabs.
Altenhofen, M.K.; Lowery, P.S.
The influence of igneous intrusions on the peak temperatures of host rocks: Finite-time emplacement, evaporation, dehydration, and decarbonation
Using a 13-m-thick basic sill and its limestone host rocks of the Permian Irati Formation from the Parana Basin, South America, as an example, this paper presents a numerical investigation based on heat conduction models on the effect of the emplacement ... Keywords: Dehydration and decarbonation, Evaporation, Igneous intrusions, Intrusion mechanism, Peak temperature
Dayong Wang; Yongchen Song; Yu Liu; Minglong Zhao; Tian Qi; Weiguo Liu
An asixymmetric diffusion experiment for the determination of diffusion and sorption coefficients of rock samples
Diffusion anisotropy is a critical property in predicting migration of substances in sedimentary formations with very low permeability. The diffusion anisotropy of sedimentary rocks has been evaluated mainly from laboratory diffusion experiments, in which the directional diffusivities are separately estimated by through-diffusion experiments using different rock samples, or concurrently by in-diffusion experiments in which only the tracer profile in a rock block is measured. To estimate the diffusion anisotropy from a single rock sample, this study proposes an axisymmetric diffusion test, in which tracer diffuses between a cylindrical rock sample and a surrounding solution reservoir. The tracer diffusion between the sample and reservoir can be monitored from the reservoir tracer concentrations, and the tracer profile could also be obtained after dismantling the sample. Semi-analytical solutions are derived for tracer concentrations in both the reservoir and sample, accounting for an anisotropic diffusion tensor of rank two as well as the dilution effects from sampling and replacement of reservoir solution. The transient and steady-state analyses were examined experimentally and numerically for different experimental configurations, but without the need for tracer profiling. These experimental configurations are tested for in- and out-diffusion experiments using Koetoi and Wakkanai mudstones and Shirahama sandstone, and are scrutinized by a numerical approach to identify favorable conditions for parameter estimation. The analysis reveals the difficulty in estimating diffusion anisotropy; test configurations are proposed for enhanced identifiability of diffusion anisotropy. Moreover, it is demonstrated that the axisymmetric diffusion test is efficient in obtaining the sorption parameter from both steady-state and transient data, and in determining the effective diffusion coefficient if isotropic diffusion is assumed. Moreover, measuring reservoir concentrations in an axisymmetric diffusion experiment coupled with tracer profiling may be a promising approach to estimate of diffusion anisotropy of sedimentary rocks.
Takeda, M.; Hiratsuka, T.; Ito, K.; Finsterle, S.
This project consists of three key interrelated Phases, each focusing on the central issue of imaging and quantifying fractured reservoirs, through improved integration of the principles of rock physics, geology, and seismic wave propagation. This report summarizes the results of Phase I of the project. The key to successful development of low permeability reservoirs lies in reliably characterizing fractures. Fractures play a crucial role in controlling almost all of the fluid transport in tight reservoirs. Current seismic methods to characterize fractures depend on various anisotropic wave propagation signatures that can arise from aligned fractures. We are pursuing an integrated study that relates to high-resolution seismic images of natural fractures to the rock parameters that control the storage and mobility of fluids. Our goal is to go beyond the current state-of-the art to develop and demonstrate next generation methodologies for detecting and quantitatively characterizing fracture zones using seismic measurements. Our study incorporates 3 key elements: (1) Theoretical rock physics studies of the anisotropic viscoelastic signatures of fractured rocks, including up scaling analysis and rock-fluid interactions to define the factors relating fractures in the lab and in the field. (2) Modeling of optimal seismic attributes, including offset and azimuth dependence of travel time, amplitude, impedance and spectral signatures of anisotropic fractured rocks. We will quantify the information content of combinations of seismic attributes, and the impact of multi-attribute analyses in reducing uncertainty in fracture interpretations. (3) Integration and interpretation of seismic, well log, and laboratory data, incorporating field geologic fracture characterization and the theoretical results of items 1 and 2 above. The focal point for this project is the demonstration of these methodologies in the Marathon Oil Company Yates Field in West Texas.
Gary Mavko
Hot dry rock venture risks investigation:
This study assesses a promising resource in central Utah as the potential site of a future commerical hot dry rock (HDR) facility for generating electricity. The results indicate that, if the HDR reservoir productivity equals expectations based on preliminary results from research projects to date, a 50 MWe HDR power facility at Roosevelt Hot Springs could generate power at cost competitive with coal-fired plants. However, it is imperative that the assumed productivity be demonstrated before funds are committed for a commercial facility. 72 refs., 39 figs., 38 tabs.
Genome, transcriptome, and secretome analysis of wood decay fungus postia placenta supports unique mechanisms of lignocellulose conversion
Brown-rot fungi such as Postia placenta are common inhabitants of forest ecosystems and are also largely responsible for the destructive decay of wooden structures. Rapid depolymerization of cellulose is a distinguishing feature of brown-rot, but the biochemical mechanisms and underlying genetics are poorly understood. Systematic examination of the P. placenta genome, transcriptome and secretome revealed unique extracellular enzyme systems, including an unusual repertoire of extracellular glycoside hydrolases. Genes encoding exocellobiohydrolases and cellulose-binding domains, typical of cellulolytic microbes, are absent in this efficient cellulose-degrading fungus. When P. placenta was grown in medium containing cellulose as sole carbon source, transcripts corresponding to many hemicellulases and to a single putative {beta}-1-4 endoglucanase were expressed at high levels relative to glucose grown cultures. These transcript profiles were confirmed by direct identification of peptides by liquid chromatography-tandem mass spectrometry (LC{center_dot}MSIMS). Also upregulated during growth on cellulose medium were putative iron reductases, quinone reductase, and structurally divergent oxidases potentially involved in extracellular generation of Fe(II) and H202. These observations are consistent with a biodegradative role for Fenton chemistry in which Fe(II) and H202 react to form hydroxyl radicals, highly reactive oxidants capable of depolymerizing cellulose. The P. placenta genome resources provide unparalleled opportunities for investigating such unusual mechanisms of cellulose conversion. More broadly, the genome offers insight into the diversification of lignocellulose degrading mechanisms in fungi. Comparisons to the closely related white-rot fungus Phanerochaete chrysosporium support an evolutionary shift from white-rot to brown-rot during which the capacity for efficient depolymerization of lignin was lost.
Martinez, Diego [Los Alamos National Laboratory; Challacombe, Jean F [Los Alamos National Laboratory; Misra, Monica [Los Alamos National Laboratory; Xie, Gary [Los Alamos National Laboratory; Brettin, Thomas [Los Alamos National Laboratory; Morgenstern, Ingo [CLARK UNIV; Hibbett, David [CLARK UNIV.; Schmoll, Monika [UNIV WIEN; Kubicek, Christian P [UNIV WIEN; Ferreira, Patricia [CIB, CSIC, MADRID; Ruiz - Duenase, Francisco J [CIB, CSIC, MADRID; Martinez, Angel T [CIB, CSIC, MADRID; Kersten, Phil [FOREST PRODUCTS LAB; Hammel, Kenneth E [FOREST PRODUCTS LAB; Vanden Wymelenberg, Amber [U. WISCONSIN; Gaskell, Jill [FOREST PRODUCTS LAB; Lindquist, Erika [DOE JGI; Sabati, Grzegorz [U. WISCONSIN; Bondurant, Sandra S [U. WISCONSIN; Larrondo, Luis F [U. CATHOLICA DE CHILE; Canessa, Paulo [U. CATHOLICA DE CHILE; Vicunna, Rafael [U. CATHOLICA DE CHILE; Yadavk, Jagiit [U. CINCINATTI; Doddapaneni, Harshavardhan [U. CINCINATTI; Subramaniank, Venkataramanan [U. CINCINATTI; Pisabarro, Antonio G [PUBLIC U. NAVARRE; Lavin, Jose L [PUBLIC U. NAVARRE; Oguiza, Jose A [PUBLIC U. NAVARRE; Master, Emma [U. TORONTO; Henrissat, Bernard [CNRS, MARSEILLE; Coutinho, Pedro M [CNRS, MARSEILLE; Harris, Paul [NOVOZYMES, INC.; Magnuson, Jon K [PNNL; Baker, Scott [PNNL; Bruno, Kenneth [PNNL; Kenealy, William [MASCOMA, INC.; Hoegger, Patrik J [GEORG-AUGUST-U.; Kues, Ursula [GEORG-AUGUST-U; Ramaiva, Preethi [NOVOZYMES, INC.; Lucas, Susan [DOE JGI; Salamov, Asaf [DOE JGI; Shapiro, Harris [DOE JGI; Tuh, Hank [DOE JGI; Chee, Christine L [UNM; Teter, Sarah [NOVOZYMES, INC.; Yaver, Debbie [NOVOZYMES, INC.; James, Tim [MCMASTER U.; Mokrejs, Martin [CHARLES U.; Pospisek, Martin [CHARLES U.; Grigoriev, Igor [DOE JGI; Rokhsar, Dan [DOE JGI; Berka, Randy [NOVOZYMES; Cullen, Dan [FOREST PRODUCTS LAB
Hot Dry Rock at Fenton Hill, USA
The Hot Dry Rock Geothermal Energy Project began in the early 1970's with the objective of developing a technology to make economically available the large ubiquitous thermal energy of the upper earth crust. The program, operated by the Los Alamos National Laboratory, has been funded by the Department of Energy (and its predecessors) and for a few years with participation by West Germany and Japan. An energy reservoir was accessed by drilling and hydraulically fracturing in the Precambrian basement rock at Fenton Hill, outside the Valles Caldera of north-central New Mexico. Water was circulated through the reservoir (Phase 1, 1978--1980) producing up to 5 MWt at 132/degree/C. A second (Phase 2) reservoir has been established with a deeper pair of holes and an initial flow test completed producing about 10 MWt at 190/degree/C. These accomplishments have been supported and paralleled by developments in drilling, well completion and instrumentation hardware. Acoustic or microseismic fracture mapping and geochemistry studies in addition to hydraulic and thermal data contribute to reservoir analyses. Studies of some of the estimated 430,000 quads of HDR resources in the United States have been made with special attention focused on sites most advantageous for early development. 17 refs., 3 figs., 1 tab.
The US Hot Dry Rock project
The Hot Dry Rock geothermal energy project began in the early 1970's with the objective of developing a technology to make economically available the large ubiquitous thermal energy of the upper earth crust. The program has been funded by the Department of Energy (and its predecessors) and for a few years with participation by West Germany and Japan. An energy reservoir was accessed by drilling and hydraulically fracturing in the precambrian basement rock outside the Valles Caldera of north-central New Mexico. Water was circulated through the reservoir (Phase I, 1978-1980) producing up to 5 MWt at 132/sup 0/C. A second (Phase II) reservoir has been established with a deeper pair of holes and an initial flow test completed producing about 10 MWt at 190/sup 0/C. These accomplishments have been supported and paralleled by developments in drilling, well completion and instrumentation hardware. Acoustic or microseismic fracture mapping and geochemistry studies in addition to hydraulic and thermal data contribute to reservoir analyses. Studies of some of the estimated 430,000 quads of HDR resources in the United States have been made with special attention focused on sites most advantageous for early development.
Comparison of quantum-mechanical and semiclassical approaches for an analysis of spin dynamics in quantum dots
Two approaches to the description of spin dynamics of electron-nuclear system in quantum dots are compared: the quantum-mechanical one is based on direct diagonalization of the model Hamiltonian and semiclassical one is based on coupled equations for precession of mean electron spin and mean spin of nuclear spin fluctuations. The comparison was done for a model problem describing periodic excitation of electron-nuclear system by optical excitation. The computation results show that scattering of parameters related to fluctuation of the nuclear spin system leads to appearance of an ordered state in the system caused by periodic excitation and to the effect of electron-spin mode locking in an external magnetic field. It is concluded that both models can qualitatively describe the mode-locking effect, however give significantly different quantitative results. This may indicate the limited applicability of the precession model for describing the spin dynamics in quantum dots in the presence of optical pumping.
Petrov, M. Yu., E-mail: email@example.com; Yakovlev, S. V. [Saint Petersburg State University (Russian Federation)
Seepage into drifts in unsaturated fractured rock at Yucca Mountain
Fractured Rock at Yucca Mountain Jens Birkholzer, Guomin Lrepository site at Yucca Mountain, Nevada, as it is locatedclimate conditions at Yucca Mountain. The numerical study is
Birkholzer, Jens; Li, Guomin; Tsang, Chin-Fu; Tsang, Yvonne
Rock Sampling At San Francisco Volcanic Field Area (Warpinski...
the target area, obtained rock samples for age dating and mineral chemistry, performed gravity and magnetic surveys, and integrated these results to identify potential drilling...
Rock Sampling At Yellowstone Region (Hellman & Ramsey, 2004)...
Hot Springs And Associated Deposits In Yellowstone National Park Using Aster And Aviris Remote Sensing Retrieved from "http:en.openei.orgwindex.php?titleRockSamplingAtYel...
Using Ornamental Rock Waste in the Manufacture of Pressed Brick ...
... is a major producer of rock trimmest, with its production destined largely for export. ... Application of Electrospun Gas Diffusion Nanofibre-membranes in the�...
Jazz and Blues Legends Rock the Northeast, Help Save Louisiana ...
U.S. Energy Information Administration (EIA)
Jazz and Blues Legends Rock the Northeast, Help Save Louisiana's Coastal Wetlands. 6.8.2006 Neville Brothers, Dr. John and Mavis Staples Highlight the ...
effect of pressure on electrical resistivity of rocks. J..exceptionally high electrical resistivity and low waterwater content is the electrical resistivity which in igneous
and R. Haught, Instrumentation evaluation, calibration, and27 - 30,1979. ROCK INSTRUMENTATION PROBLEMS EXPERIENCEDdiscussed here,l INSTRUMENTATION AND DATA ACQUISITION SYSTEM
Binnall, E.
Paradox Basin source rock, southeastern Utah : organic geochemical characterization of Gothic and Chimney Rock units, Ismay and Desert Creek zones, within a sequence stratigraphic framework.
??The Chimney Rock and Gothic units of the Pennsylvanian Paradox Formation have long been considered source rocks for the rich hydrocarbon fields of southeastern Utah.� (more)
Tischler, Keith Louris
Geochemistry of Sediments from the Rock Analysis Storage System...
Contact Email Unique Identifier DOI-26 Public Access Level public Data Dictionary included in metadata Data Download URL http:tin.er.usgs.govplutosoil...
Isotopic Analysis- Rock At Valles Caldera - Sulphur Springs Area...
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Rapid excavation by rock melting (LASL Subterrene Program). Status report, September 1973--June 1976
Research was directed at establishing the technical and economic feasibility of excavation systems based upon the rock-melting (Subterrene) concept. A series of electrically powered, small-diameter prototype melting penetrators was developed and tested. Research activities include optimizing penetrator configurations, designing high-performance heater systems, and improving refractory metals technology. The properties of the glass linings that are automatically formed on the melted holes have been investigated for a variety of rocks and soils. Thermal and fluid-mechanics analyses of the melt flows were conducted with the objective of optimizing penetrator designs. Field tests and demonstrations of the prototype devices continue to be performed in a wide range of rock and soil types. Primary emphasis was placed on the development of a penetrator designed for more economical extraction of geothermal energy and of small-diameter penetrators which can be utilized in support of geothermal energy exploration programs. Optimization of well design, the trade-off of advance rate with operating life, the advantages of using the melt-glass hole casing for well-bore seal-off, rig automation, and the benefits which result from the insensitivity of rock melting to formation temperatures and geologic variations were also studied. Subsystem hardware development was directed toward resolution of critical technical questions related to penetrators for dense rock, debris handling, electrical heater configuration, and establishing penetrator life. Laboratory experiments and field tests provide data for final system design optimizations and indicate proof of applicability of the concept to a geothermal well hole-forming system. A field test unit to form relatively shallow vertical holes for heat flow surveys in support of geothermal exploration studies has been designed, fabricated, and field tested.
Hanold, R.J. (comp.)
This paper presents an ongoing experimental program on unreinforced masonry walls undergoing free rocking. Aim of the laboratory campaign is the estimation of kinetic energy damping exhibited by walls released with non-zero initial conditions of motion. Such energy damping is necessary for dynamic modelling of unreinforced masonry local mechanisms. After a brief review of the literature on this topic, the main features of the laboratory tests are presented. The program involves the experimental investigation of several parameters: 1) unit material (brick or tuff), 2) wall aspect ratio (ranging between 14.5 and 7.1), 3) restraint condition (two-sided or one-sided rocking), and 4) depth of the contact surface between facade and transverse walls (one-sided rocking only). All walls are single wythe and the mortar is pozzuolanic. The campaign is still in progress. However, it is possible to present the results on most of the mechanical properties of mortar and bricks. Moreover, a few time histories are reported, already indicating the need to correct some of the assumptions frequent in the literature.
Sorrentino, Luigi; Masiani, Renato; Benedetti, Stefano [Dipartimento di Ingegneria Strutturale e Geotecnica, Sapienza Universita di Roma, via Antonio Gramsci, 53-00197 Roma (Italy)
Bohmian Mechanics
Bohmian mechanics is a theory about point particles moving along trajectories. It has the property that in a world governed by Bohmian mechanics, observers see the same statistics for experimental results as predicted by quantum mechanics. Bohmian mechanics thus provides an explanation of quantum mechanics. Moreover, the Bohmian trajectories are defined in a non-conspiratorial way by a few simple laws.
Detlef Duerr; Sheldon Goldstein; Roderich Tumulka; Nino Zanghi
Mechanical down jar mechanism
This paper describes a mechanical down jar mechanism for freeing stuck objects within a well bore and for conducting other down hole activities. It comprises: an elongate tubular housing having anvil means; mandrel means adapted for connection to an object to be moved downwardly within the well bore and being disposed in telescoping relation with the anvil means and the elongate tubular housing, the mandrel means adapted to be struck by the anvil means to impart a downwardly directed jarring force to the object; the elongate tubular housing having internal firing and recocking detent groove means located in axially spaced relation and forming a firing lug support land therebetween; a radially expandable and retractable firing lug assembly being disposed within the elongate tubular housing and in absence of force being applied axially thereto being radially restrained by the firing lug support land; load spring means being disposed within the elongate tubular housing and being in downward force transmitting relation with the firing lug assembly; recocking spring means being disposed within the elongate tubular housing and having upward axial force transmitting relation with the firing lug assembly.
Taylor, W.T.
Fluid effects on seismic waves in hard rocks with fractures and in soft granular media
When fractures in otherwise hard rocks are filled with fluids (oil, gas, water, CO{sub 2}), the type and physical state of the fluid (liquid or gas) can make a large difference in the wave speeds and attenuation properties of seismic waves. The present work summarizes methods of deconstructing theses effects of fractures, together with any fluids contained within them, on wave propagation as observed in reflection seismic data. Additional studies of waves in fluid-saturated granular media show that the behavior can be quite different from that for fractured media, since these materials are typically much softer mechanically than are the fractured rocks (i.e., having a very small drained moduli). Important fluid effects in such media are often governed as much by fluid viscosity as by fluid bulk modulus.
Berryman, James G.
Rock Rapids Municipal Utility | Open Energy Information
Rapids Municipal Utility Rapids Municipal Utility Jump to: navigation, search Name Rock Rapids Municipal Utility Place Iowa Utility Id 16206 Utility Location Yes Ownership M NERC Location MRO NERC MRO Yes Operates Generating Plant Yes Activity Generation Yes Activity Transmission Yes Activity Buying Transmission Yes Activity Distribution Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png Commercial Power (Single-Phase) Commercial Commercial Power (Three-Phase) Commercial Residential Power Residential Average Rates Residential: $0.0807/kWh Commercial: $0.0633/kWh Industrial: $0.0899/kWh
High-Velocity Rocks Final Report
The objective of our research was to develop and demonstrate seismic data-acquisition and data-processing technologies that allow geothermal prospects below high-velocity rock outcrops to be evaluated. To do this, we acquired a 3-component seismic test line across an area of exposed high-velocity rocks in Brewster County, Texas, where there is high heat flow and surface conditions mimic those found at numerous geothermal prospects. Seismic contractors have not succeeded in creating good-quality seismic data in this area for companies who have acquired data for oil and gas exploitation purposes. Our test profile traversed an area where high-velocity rocks and low-velocity sediment were exposed on the surface in alternating patterns that repeated along the test line. We verified that these surface conditions cause non-ending reverberations of Love waves, Rayleigh waves, and shallow critical refractions to travel across the earth surface between the boundaries of the fast-velocity and slow-velocity material exposed on the surface. These reverberating surface waves form the high level of noise in this area that does not allow reflections from deep interfaces to be seen and utilized. Our data-acquisition method of deploying a box array of closely spaced geophones allowed us to recognize and evaluate these surface-wave noise modes regardless of the azimuth direction to the surface anomaly that backscattered the waves and caused them to return to the test-line profile. With this knowledge of the surface-wave noise, we were able to process these test-line data to create P-P and SH-SH images that were superior to those produced by a skilled seismic data-processing contractor. Compared to the P-P data acquired along the test line, the SH-SH data provided a better detection of faults and could be used to trace these faults upward to the boundaries of exposed surface rocks. We expanded our comparison of the relative value of S-wave and P-wave seismic data for geothermal applications by inserting into this report a small part of the interpretation we have done with 3C3D data across Wister geothermal field in the Imperial Valley of California. This interpretation shows that P-SV data reveal faults (and by inference, also fractures) that cannot be easily, or confidently, seen with P-P data, and that the combination of P-P and P-SV data allows VP/VS velocity ratios to be estimated across a targeted reservoir interval to show where an interval has more sandstone (the preferred reservoir facies). The conclusion reached from this investigation is that S-wave seismic technology can be invaluable to geothermal operators. Thus we developed a strong interest in understanding the direct-S modes produced by vertical-force sources, particularly vertical vibrators, because if it can be demonstrated that direct-S modes produced by vertical-force sources can be used as effectively as the direct-S modes produced by horizontal-force sources, geothermal operators can acquire direct-S data across many more prospect areas than can be done with horizontal-force sources, which presently are limited to horizontal vibrators. We include some of our preliminary work in evaluating direct-S modes produced by vertical-force sources.
Hardage, Bob A; DeAngelo, Michael V; Ermolaeva, Elena; Hardage, Bob A; Remington, Randy; Sava, Diana; Wagner, Donald; Wei, Shuijion
Hot dry rock Phase II reservoir engineering
Early attempts to hydraulically fracture and connect two wells drilled at the Hot Dry Rock site at Fenton Hill in New Mexico failed. Microearthquakes triggered by hydraulic fracturing indicated that the fracture zones grew in unexpected directions. Consequently one of the wells was sidetracked at a depth of 2.9 km; was redrilled into the zones of most intense microseismic activity; and a flow connection was achieved. Hydraulic communication was improved by supplemental fracturing using recently developed high temperature and high pressure open hole packers. Preliminary testing indicates a reservoir with stimulated joint volume which already surpasses that attained in the earlier phase I reservoir after several years of development. 12 refs., 6 figs.
Mechanical design and analysis of an eight-pole superconducting vector magnet for soft x-ray magnetic dichroism measurements
An eight-pole superconducting magnet is being developed for soft x-ray magnetic dichroism (XMD) experiments at the Advanced Light Source, Lawrence Berkley National Laboratory (LBNL). Eight conical Nb{sub 3}Sn coils with Holmium poles are arranged in octahedral symmetry to form four dipole pairs that provide magnetic fields of up to 5 T in any direction relative to the incoming x-ray beam. The dimensions of the magnet yoke as well as pole taper, diameter, and length were optimized for maximum peak field in the magnet center using the software package TOSCA. The structural analysis of the magnet is performed using ANSYS with the coil properties derived using a numerical homogenization scheme. It is found that the use of orthotropic material properties for the coil has an important influence in the design of the magnet.
Arbelaez, D.; Black, A.; Prestemon, S.O.; Wang, S.; Chen, J.; Arenholz, E.
Determining inert content in coal dust/rock dust mixture
A method and apparatus for determining the inert content of a coal dust and rock dust mixture uses a transparent window pressed against the mixture. An infrared light beam is directed through the window such that a portion of the infrared light beam is reflected from the mixture. The concentration of the reflected light is detected and a signal indicative of the reflected light is generated. A normalized value for the generated signal is determined according to the relationship .phi.=(log i.sub.c `log i.sub.co) / (log i.sub.c100 -log i.sub.co) where i.sub.co =measured signal at 0% rock dust i.sub.c100 =measured signal at 100% rock dust i.sub.c =measured signal of the mixture. This normalized value is then correlated to a predetermined relationship of .phi. to rock dust percentage to determine the rock dust content of the mixture. The rock dust content is displayed where the percentage is between 30 and 100%, and an indication of out-of-range is displayed where the rock dust percent is less than 30%. Preferably, the rock dust percentage (RD%) is calculated from the predetermined relationship RD%=100+30 log .phi.. where the dust mixture initially includes moisture, the dust mixture is dried before measuring by use of 8 to 12 mesh molecular-sieves which are shaken with the dust mixture and subsequently screened from the dust mixture.
Sapko, Michael J. (Finleyville, PA); Ward, Jr., Jack A. (Oakmont, PA)
Discrete element modeling of rock deformation, fracture network development and permeability evolution under hydraulic stimulation
Key challenges associated with the EGS reservoir development include the ability to reliably predict hydraulic fracturing and the deformation of natural fractures as well as estimating permeability evolution of the fracture network with time. We have developed a physics-based rock deformation and fracture propagation simulator by coupling a discrete element model (DEM) for fracturing with a network flow model. In DEM model, solid rock is represented by a network of discrete elements (often referred as particles) connected by various types of mechanical bonds such as springs, elastic beams or bonds that have more complex properties (such as stress-dependent elastic constants). Fracturing is represented explicitly as broken bonds (microcracks), which form and coalesce into macroscopic fractures when external and internal load is applied. The natural fractures are represented by a series of connected line segments. Mechanical bonds that intersect with such line segments are removed from the DEM model. A network flow model using conjugate lattice to the DEM network is developed and coupled with the DEM. The fluid pressure gradient exerts forces on individual elements of the DEM network, which therefore deforms the mechanical bonds and breaks them if the deformation reaches a prescribed threshold value. Such deformation/fracturing in turn changes the permeability of the flow network, which again changes the evolution of fluid pressure, intimately coupling the two processes. The intimate coupling between fracturing/deformation of fracture networks and fluid flow makes the meso-scale DEM- network flow simulations necessary in order to accurately evaluate the permeability evolution, as these methods have substantial advantages over conventional continuum mechanical models of elastic rock deformation. The challenges that must be overcome to simulate EGS reservoir stimulation, preliminary results, progress to date and near future research directions and opportunities will be discussed. Methodology for coupling the DEM model with continuum flow and heat transport models will also be discussed.
Shouchun Deng; Robert Podgorney; Hai Huang
Cumulative experience of the US Hot Dry Rock Program
In over 20 years of research on the Hot Dry Rock (HDR) geothermal energy concept at Los Alamos National Laboratory, no obstacle has yet been found that would prevent its development as a major new energy source for the nation. To put the continuing development of the HDR concept in perspective, the most appropriate comparison is with fusion energy, the only other nonrenewable energy resource of the magnitude of HDR geothermal energy. In this context, research on fusion energy is currently so far from the demonstration stage that obstacles to its ultimate commercial development, such as induced radiation or neutron damage to structural materials, cannot yet be addressed from the standpoint of engineered solutions. For the commercialization of the HDR concept, on the other hand, we know what technical problems remain and are presently developing engineered solutions to address each of them. This document presents learned information on: the formation of HDR reservoirs; the structure of the deep precambrian basement; the mechanics of creating an HDR geothermal reservoir; peripheral water loss from deep HDR reservoirs; the determination of the size, orientation, and internal structure of the stimulated HDR region; and results from geochemical analyses and tracer testing.
Foam flow through a transparent rough-walled rock fracture
This paper presents an experimental study of nitrogen, water, and aqueous foam flow through a transparent replica of a natural rough-walled rock fracture with a hydraulic aperture of roughly 30 {mu}m. It is established that single-phase flow of both nitrogen and water is well described by analogy to flow between parallel plates. Inertial effects caused by fracture roughness become important in single-phase flow as the Reynolds number approaches 1. Foam exhibits effective control of gas mobility. Foam flow resistances are approximately 10 to 20 times greater than those of nitrogen over foam qualities spanning from 0.60 to 0.99 indicating effective gas-mobility control. Because previous studies of foam flow have focused mainly upon unfractured porous media, little information is available about foam flow mechanisms in fractured media. The transparency of the fracture allowed flow visualization and demonstrated that foam rheology in fractured media depends upon bubble shape and size. Changes in flow behavior are directly tied to transitions in bubble morphology.
Kovscek, A.; Tretheway, D.; Radke, C. [and others
Development of Advanced Thermal-Hydrological-Mechanical-Chemical (THMC)
Thermal-Hydrological-Mechanical-Chemical (THMC) Thermal-Hydrological-Mechanical-Chemical (THMC) Modeling Capabilities for Enhanced Geothermal Systems Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Development of Advanced Thermal-Hydrological-Mechanical-Chemical (THMC) Modeling Capabilities for Enhanced Geothermal Systems Project Type / Topic 1 Recovery Act: Enhanced Geothermal Systems Component Research and Development/Analysis Project Type / Topic 2 Integrated Chemical, Thermal, Mechanical and Hydrological Modeling Project Description The proposed research will make significant contributions to assessing, developing, and managing EGS systems. The research results will directly address many of key aspects of developing EGS and traditional geothermal reservoirs from site selection and characterization, reservoir creation, stimulation, and validation to reservoir sustainability. In particular, the proposed development provides a practical approach to assess long-term performance of EGS systems as well as optimum design and operation strategies, by consideration of fully coupled processes of thermal, hydrological, geochemical, and rock deformation effects. This research is strategically important to DOE's mission in the national energy resource and security. Furthermore, once the research goals are achieved, the developed simulator will substantially enhance the ability to characterized EGS systems, predict long-term performance of EGS systems, and optimize production strategies, and help energy extraction from EGS reservoir commercially feasible.
Liquid impact erosion mechanism and theoretical impact stress analysis in TiN-coated steam turbine blade materials
Coating of TiN film was done by reactive magnetron sputter ion plating to improve the liquid impact erosion resistance of steam turbine blade materials, 12Cr steel and Stellite 6B, for nuclear power plant application. TiN-coated blade materials were initially deformed with depressions due to plastic deformation of the ductile substrate. The increase in the curvature in the depressions induced stress concentration with increasing number of impacts, followed by circumferential fracture of the TiN coating due to the circular propagation of cracks. The liquid impact erosion resistance of the blade materials was greatly improved by TiN coating done with the optimum ion plating condition. Damage decreased with increasing TiN coating thickness. According to the theoretical analysis of stresses generated by liquid impact, TiN coating alleviated the impact stress of 12Cr steel and Stellite 6B due to stress attenuation and stress wave reactions such as reflection and transmission at the coating-substrate interface.
Lee, M.K.; Kim, W.W.; Rhee, C.K.; Lee, W.J. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Dept. of Materials Science and Engineering
Property:HostRockLithology | Open Energy Information
HostRockLithology HostRockLithology Jump to: navigation, search Property Name HostRockLithology Property Type String Description Condensed description of the lithology of the reservoir rock. This is a property of type Page. Subproperties This property has the following 14 subproperties: B Beowawe Hot Springs Geothermal Area Brady Hot Springs Geothermal Area C Chena Geothermal Area D Desert Peak Geothermal Area G Geysers Geothermal Area H Heber Geothermal Area L Lightning Dock Geothermal Area R Raft River Geothermal Area Roosevelt Hot Springs Geothermal Area S Salton Sea Geothermal Area Steamboat Springs Geothermal Area S cont. Stillwater Geothermal Area V Valles Caldera - Sulphur Springs Geothermal Area W Wabuska Hot Springs Geothermal Area Pages using the property "HostRockLithology"
Property:HostRockAge | Open Energy Information
HostRockAge HostRockAge Jump to: navigation, search Property Name HostRockAge Property Type String Description Describes the age of the reservoir rock by epoch, era, or period per available data. This is a property of type Page. Subproperties This property has the following 10 subproperties: B Beowawe Hot Springs Geothermal Area Brady Hot Springs Geothermal Area C Chena Geothermal Area D Desert Peak Geothermal Area G Geysers Geothermal Area R Raft River Geothermal Area Roosevelt Hot Springs Geothermal Area S Salton Sea Geothermal Area Steamboat Springs Geothermal Area W Wabuska Hot Springs Geothermal Area Pages using the property "HostRockAge" Showing 11 pages using this property. A Amedee Geothermal Area + Mesozoic + B Blue Mountain Geothermal Area + Triassic + C Coso Geothermal Area + Mesozoic +
Electrical Conductivity of Soils and Rocks | Open Energy Information
form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit with form History Facebook icon Twitter icon » Electrical Conductivity of Soils and Rocks Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Electrical Conductivity of Soils and Rocks Author J.D. McNeill Organization Geonics Limited Published Geonics Limited, 1980 Report Number TN-5 DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for Electrical Conductivity of Soils and Rocks Citation J.D. McNeill (Geonics Limited). 1980. Electrical Conductivity of Soils and Rocks. TN-5 Edition. ?: Geonics Limited. Report No.: TN-5. Retrieved from "http://en.openei.org/w/index.php?title=Electrical_Conductivity_of_Soils_and_Rocks&oldid=695344"
Rock Density At Alum Area (DOE GTP) | Open Energy Information
Rock Density At Alum Area (DOE GTP) Rock Density At Alum Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Rock Density At Alum Geothermal Area (DOE GTP) Exploration Activity Details Location Alum Geothermal Area Exploration Technique Rock Density Activity Date Usefulness not indicated DOE-funding Unknown References (1 January 2011) GTP ARRA Spreadsheet Retrieved from "http://en.openei.org/w/index.php?title=Rock_Density_At_Alum_Area_(DOE_GTP)&oldid=402985" Categories: Exploration Activities DOE Funded Activities ARRA Funded Activities What links here Related changes Special pages Printable version Permanent link Browse properties About us Disclaimers Energy blogs Linked Data Developer services OpenEI partners with a broad range of international organizations to grow
Rock Sampling At Coso Geothermal Area (1995) | Open Energy Information
source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Rock Sampling At Coso Geothermal Area (1995) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Rock Sampling At Coso Geothermal Area (1995) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Rock Sampling Activity Date 1995 Usefulness not indicated DOE-funding Unknown Notes Geologic controls on the geometry of the upwelling plume were investigated using petrographic and analytical analyses of reservoir rock and vein material. References Lutz, S.J.; Moore, J.N. ; Copp, J.F. (1 June 1995) Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal Area,
Property:CapRockLithology | Open Energy Information
CapRockLithology CapRockLithology Jump to: navigation, search Property Name CapRockLithology Property Type String Description Condensed description of the lithology of the cap rock. Subproperties This property has the following 6 subproperties: B Beowawe Hot Springs Geothermal Area Brady Hot Springs Geothermal Area D Desert Peak Geothermal Area E East Mesa Geothermal Area H Heber Geothermal Area S Salton Sea Geothermal Area Pages using the property "CapRockLithology" Showing 6 pages using this property. A Amedee Geothermal Area + volcanic; lacustrine sediments + B Blue Mountain Geothermal Area + Hydrothermal alteration layer + G Geysers Geothermal Area + Hydrothermal alteration layer + K Kilauea East Rift Geothermal Area + Overlapping a'a' and pahoehoe flows + L Long Valley Caldera Geothermal Area + Metasedimentary Landslide Block; Hydrothermal Alteration Layer +
Rock Hill Utilities - Water Heater and Heat Pump Rebate Program |
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
Rock Hill Utilities - Water Heater and Heat Pump Rebate Program Rock Hill Utilities - Water Heater and Heat Pump Rebate Program Rock Hill Utilities - Water Heater and Heat Pump Rebate Program < Back Eligibility Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heat Pumps Appliances & Electronics Water Heating Program Info State South Carolina Program Type Utility Rebate Program Rebate Amount Water Heater: up to $275 Heat Pump Replacement: $400 Provider Rock Hill Utilities Through the SmartChoice program, Rock Hill Utilities offers rebates for water heater and heat pump replacements. Information on financing for heat pumps can also be found on the web site listed above. If both the water heater and heat pump are purchased then the customer may qualify for the Great Rate program. The Great Rate program will add a 25% discount to a
Analysis of Percent On-Cell Reformation of Methane in SOFC Stacks and the Effects on Thermal, Electrical, and Mechanical Performance
Numerical simulations were performed to determine the effect that varying the percent on-cell steam-methane reformation would have on the thermal, electrical, and mechanical performance of generic, planar solid oxide fuel cell stacks. The study was performed using three-dimensional model geometries for cross-, co-, and counter-flow configuration stacks of 10x10- and 20x20-cm cell sizes. The analysis predicted the stress and temperature difference would be minimized for the 10x10-cm counter- and cross-flow stacks when 40 to 50% of the reformation reaction occurred on the anode. Gross electrical power density was virtually unaffected by the reforming. The co-flow stack benefited most from the on-cell reforming and had the lowest anode stresses of the 20x20-cm stacks. The analyses also suggest that airflows associated with 15% air utilization may be required for cooling the larger (20x20-cm) stacks.
Recknagle, Kurtis P.; Koeppel, Brian J.; Sun, Xin; Khaleel, Mohammad A.; Yokuda, Satoru T.; Singh, Prabhakar
Full waveform inversion of a 3-D source inside an artificial rock
of a 3-D Source Inside an Artificial Rock Albert C. To andof a 3-D source inside an artificial rock plate inof a 3-D source inside an artificial rock plate is
To, A C; Glaser, Steven D
Bohmian mechanics contradicts quantum mechanics
Bohmian mechanics contradicts quantum mechanics Arnold Neumaier Institut fur Mathematik, Universit://solon.cma.univie.ac.at/#24;neum/ Abstract. It is shown that, for a harmonic oscillator in the ground state, Bohmian mechanics and quantum mechanics predict values of opposite sign for certain time correlations. The discrepancy can
Neumaier, Arnold
Modeling rock fracturing in bench-blasting problems
A computational model of rock blasting is being developed to examine the blasting problems associated with in situ oil shale processing. This model, however, will also be useful as a design tool for the traditional problems in rock blasting. The model includes fundamental treatment of both shock-wave propagation and the accumulation of brittle fracture in the rock. As a result, the model accurately predicts the degree and extent of fracturing as functions of design parameters. The model has proven useful for making parametric studies and for evaluation of alternate blast designs. This paper demonstrates the use of the numerical model to simulate the fracturing induced by the detonation of a vertical explosive column near a bench. The fracturing induced by three different explosives indicate that (in the chosen geometry) the most efficient breakage is done by a column of ammonium nitrate and fuel oil mixture (ANFO) used with a toe charge of aluminized ANFO. There was too much unfractured rock left when ANFO was used alone; aluminized ANFO used for the entire explosive column caused excessive fracturing. A final case involves ANFO used alone to fracture a different rock type. This case points out that in a different rock type, the ANFO will not leave excessive unfractured rock.
Kuszmaul, J.S.
The overall objective of the Hot Dry Rock (HDR) Geothermal Energy Development Program is to determine the technical and economic feasibility of HDR as a significant energy source and to provide a basis for its timely commercial development. Principal operational tasks are those activities required to enable a decision to be made by FY86 on the ultimate commercialization of HDR. These include development and analyis of a 20- to 50-MW Phase II HDR reservoir at Site 1 (Fenton Hill) with the potential construction of a pilot electric generating station, Phase III; selection of a second site with subsequent reservoir development and possible construction of a direct heat utilization pilot plant of at least 30 MW thermal thereon; the determination of the overall domestic HDR energy potential; and the evaluation of 10 or more target prospect areas for future HDR plant development by commercial developers. Phase I of the Los Alamos Scientific Laboratory's Fenton Hill project was completed. Phase I evaluated a small subterranean system comprised of two boreholes connected at a depth of 3 km by hydraulic fracturing. A closed-loop surface system has been constructed and tests involving round-the-clock operation have yielded promising data on heat extraction, geofluid chemistry, flow impedance, and loss of water through the underground reservoir between the two holes, leading to cautions optimism for the future prospects of private-sector HDR power plants. (MHR)
Franke, P.R.
Rock Sampling At The Needles Area (Kratt, Et Al., 2005) | Open Energy
The Needles Area (Kratt, Et Al., 2005) The Needles Area (Kratt, Et Al., 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Rock Sampling At The Needles Area (Kratt, Et Al., 2005) Exploration Activity Details Location The Needles Area Exploration Technique Rock Sampling Activity Date Usefulness not indicated DOE-funding Unknown Notes Over 2000 km2 of 5-m resolution Hymap hyperspectral data was acquired in 2004. Subsequent image processing and data analysis has identified reflectance spectra for alunite, kaolinite/halloysite, illite, gypsum, vegetation, and carbonate. A portable spectrometer is being used for in situ validation, along with laboratory measurements and x-ray diffraction analyses of samples collected in teh field. We are in the process of producing and validating mineral maps that will be used to narrow the scope
Dual-energy neutron tomography of water in rock using the Argonne IPNS
In dual-energy hydrogen imaging, the increase in hydrogen neutron cross-section at subthermal neutron energies is used to enhance the imaging of small amounts of hydrogen against a background of other absorbing materials by subtracting a tomographic image obtained for higher energy neutrons from that obtained for subthermal neutrons (picking energies such that the other absorbing materials have nearly the same cross-sections at both energies). This technique was used to provide dual-energy imaging of water in tuffaceous rock, with the goal being to track water flow through porous rock for site risk analysis of permanent disposal of radwaste. A feasibility experiment was conducted at the IPNS facility with coarse spatial resolution, yielding promising results.
Rhodes, E.; Kupperman, D.S.; Hitterman, R.L.
Excellent progress has been made on all project objectives and goals. All tasks have been completed in the Phase 1 study area, the initial area of project focus. Primary elements of this work include the following: The stratigraphic architecture has been established through correlation of wireline logs guided by core and outcrop studies of facies and cyclicity. A porosity model has been developed that creates a basis for calculation of porosity for wells in the study area. Rock fabrics have been defined by sampling, analysis, and description of cores and used to create transforms for calculating permeability and oil saturation from porosity data. Finally, a preliminary 3-D model has been constructed that incorporates stratigraphic architecture, rock-fabric data, and petrophysical data. Reservoir volumetrics calculated from the model show that a very large fraction of the original oil in place remains.
Stephen C. Ruppel
A coupled model of fluid flow in jointed rock
We present a fully coupled model of fluid flow in jointed rock, where the fluid flow depends on the joint openings and the joint openings depend on the fluid pressure. The joints and rock blocks are modeled discretely using the finite element method. Solutions for the fluid and rock are obtained and iteration is performed until both solutions converge. Example applications include an examination of the effects of back-pressure on flow in a geothermal reservoir and transient fluid injection into a reservoir.
Swenson, Daniel; Martineau, Rick; James, Mark; Brown, Don
EA-1897: AltaRock's Newberry Volcano EGS Demonstration near Bend...
7: AltaRock's Newberry Volcano EGS Demonstration near Bend, Oregon EA-1897: AltaRock's Newberry Volcano EGS Demonstration near Bend, Oregon Summary This EA evaluates the...
Masses. FIELD TESTS FOR RADIONUCLIDE TRANSPORT . BOREHOLE,Rock Masses � . Radionuclide Field Tests. � Borehole andaints. � � � . Barriers to Radionuclide Movement. � THE ROCK
Authors, Various
Evaluation of CAVIJET cavitating jets for deep-hole rock cutting
A feasibility study has shown that the CAVIJET cavitating fluid jet method should be capable of successfully augmenting the cutting action of mechanical bits under deep-hole conditions. Increased rock cutting rates by existing cavitating jet nozzles can be anticipated with conventional rig pressures for hole depths of at least 1200 m (4000 ft) and possibly deeper. Improved rates of penetration, based on preliminary laboratory roller bit tests, should be achieved by simply substituting CAVIJET nozzles absorbing equivalent hydraulic power for conventional roller bit nozzles.
Conn, A.F.; Johnson, V.E. Jr.; Liu, H.L.; Frederick, G.S.
An Analytical Model for Solute Transport in Unsaturated Flow through a Single Fracture and Porous Rock Matrix
fracture � matrix solute source rock matrix rock matrix vin fracture; b) solute source in rock matrix. Draft 8-11-04for a point source in the rock matrix are presented in
Houseworth, J.E.
Waste/Rock Interactions Technology Program: the status of radionuclide sorption-desorption studies performed by the WRIT program
The most credible means for radionuclides disposed as solid wastes in deep-geologic repositories to reach the biosphere is through dissolution of the solid waste and subsequent radionuclide transport by circulating ground water. Thus safety assessment activities must consider the physicochemical interactions between radionculides present in ground water with package components, rocks and sediments since these processes can significantly delay or constrain the mass transport of radionuclides in comparison to ground-water movement. This paper focuses on interactions between dissolved radiouclides in ground water and rocks and sediments away from the near-field repository. The primary mechanism discussed is adsorption-desorption, which has been studied using two approaches. Empirical studies of adsorption-desorption rely on distribution coefficient measurements while mechanism studies strive to identify, differentiate and quantify the processes that control nuclide retardation.
Serne, R.J.; Relyea, J.F.
Sliding and Rocking of Unanchored Components and Structures: Chapter 7.6 ASCE 4 Revision 2
Chapter 7.6 of ASCE 4-Rev 2, Seismic Analysis of Safety-Related Nuclear Structures: Standard and Commentary, provides updated guidance for analysis of rocking and sliding of unanchored structures and components subjected to seismic load. This guidance includes provisions both for simplified approximate energy-based approaches, and for detailed probabilistic time history analysis using nonlinear methods. Factors to be applied to the analytical results are also provided with the intent of ensuring achievement of the 80% non-exceedence probability target of the standard. The present paper surveys the published literature supporting these provisions. The results of available testing and analysis are compared to results produced by both simplified and probabilistic approaches. In addition, adequacy of the standard's provisions for analysis methods and factors is assessed. A comparison is made between the achieved level of conservatism and the standard's non-exceedence probability target.
S. R. Jensen
Rock deformation in hydrothermal systems: the nature of fractures in plutons and their host rocks. Technical progress report
The purpose of this program is to accumulate the types of field data which are important for the analysis of magma-hydrothermal systems. The structural effects of thermal processes were identified in order to distinguish the thermally induced deformations from the deformations that occurred subsequent to complete cooling of the system. Mapping techniques were developed to record the structural data on the ground from local domains characteristic of larger areas in the magma chamber, and in the air from low-angle oblique aerial photography of the entire region. The ground system is complete and preliminary testing is currently being carried out to verify the method. The results indicate that granitic crystalline rocks have no structural resistance to thermal perturbations. If nuclear wastes are to be stored in granite, precautionary buffers would have to be incorporated into the system. A total of 30 fossil magma chambers have been studied over the past 2 years. An extensive set of fracture imagery has been collected, together with information related to the geological history of the plutons. Fossil magma chambers in Arizona, Utah, California, Washington, Montana, and British Columbia have been studied.
Norton, D.
DOE - Office of Legacy Management -- Rock Island Arsenal - IL 09
Rock Island Arsenal - IL 09 Rock Island Arsenal - IL 09 FUSRAP Considered Sites Site: ROCK ISLAND ARSENAL ( IL.09 ) Eliminated from consideration under FUSRAP - Referred to DOD Designated Name: Not Designated Alternate Name: None Location: Rock Island , Illinois IL.09-1 Evaluation Year: 1987 IL.09-2 Site Operations: Site located on a DOD facility and operated under AEC control. Exact nature or time period of operations not clear. No indication that radioactive materials were involved. Contract work with Albuquerque Operations office performed. IL.09-1 IL.09-2 Site Disposition: Eliminated - No Authority - Referred to DOD IL.09-2 Radioactive Materials Handled: None Indicated IL.09-2 Primary Radioactive Materials Handled: None Indicated Radiological Survey(s): None Indicated
DOE - Office of Legacy Management -- WNI Split Rock Site - 043
Split Rock Site - 043 Split Rock Site - 043 FUSRAP Considered Sites Site: WNI Split Rock Site (043) Designated Name: Alternate Name: Location: Evaluation Year: Site Operations: Site Disposition: Radioactive Materials Handled: Primary Radioactive Materials Handled: Radiological Survey(s): Site Status: The Western Nuclear, Inc. (WNI) Split Rock site is a Uranium Mill Tailings Remedial Action (UMTRA) Title II site located in Jeffrey City, Wyoming. UMTRA Title II sites are privately owned and operated sites that were active when the Uranium Mill Tailings Control Act was passed in 1978. The majority of the milling conducted at these sites was for private sale, but a portion was sold to the U.S. Government. After the owner completes U.S. Nuclear Regulatory Commission license termination, the Department of
Photo of the Week: Laser Beats Rock | Department of Energy
Laser Beats Rock Laser Beats Rock Photo of the Week: Laser Beats Rock April 8, 2013 - 5:28pm Addthis On August 5, 2012, the Curiosity rover touched down on the surface of Mars. The ChemCam instrument package, developed at Los Alamos National Laboratory, is a device mounted on the Mars Curiosity rover that uses two remote sensing instruments: the Laser-Induced Breakdown Spectrometer (LIBS) and a Remote Micro-Imager (RMI). The LIBS fires a powerful laser that determines chemical compositions of rock and soil samples, while the RMI takes photos of the samples within the rover's vicinity. In this photo, the ChemCam is being prepared in the clean room prior to the launch of NASA's Mars Science Laboratory mission. Learn more about the ChemCam. | Photo courtesy of Los Alamos National Laboratory.
Permeability Estimation From Velocity Anisotropy In Fractured Rock
Cracks in a rock mass subjected to a uniaxial stress will be preferentially closed depending on the angle between the fracture normal vectors and the direction of the applied stress. If the prestress fracture orientation ...
Gibson, Richard L., Jr.
Figure 2. Stratigraphic Summary of Ages, Names and Rock Types...
U.S. Energy Information Administration (EIA) Indexed Site
2. Stratigraphic Summary of Ages, Names and Rock Types in the ANWR 1002 and Coastal Plain Area of the Alaska North Slope. Potentially Productive Reservoirs and Plays Assessed by...
Influence of soil parameters on the motion of rocking walls
Introduced as a system in earthquake engineering in 2004 [6], rocking walls are a fairly new system in earthquake engineering. Their performance has been proven, both in research as in practice. However, a few uncertainties ...
Houbrechts, Jeroen J. J. (Jeroen Jose Julien)
Laser Rock Drilling Demo - The NE Multimedia Collection
Demo A high power pulsed Nd:YAG laser beam at Argonne's Laser Applications Lab is being shown in this movie to drill oil reservoir rock, a potential application in gas and oil well...
Laser Spallation of Rocks for Oil Well Drilling
LASER SPALLATION OF ROCKS FOR OIL WELL DRILLING Zhiyue Xu 1 , Claude B. Reed 1 , Richard Parker 2 , Ramona Graves 3 1 Argonne National Laboratory, Argonne, IL 60439, USA 2 Parker...
Geothermal: Sponsored by OSTI -- CO2-Rock Interactions in EGS...
CO2-Rock Interactions in EGS-CO2: New Zealand TVZ Geothermal Systems as a Natural Analog Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us | Admin Log On...
Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal
Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal Area, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal Area, California Details Activities (1) Areas (1) Regions (0) Abstract: Coso is one of several high-temperature geothermal systems associated with recent volcanic activity in the Basin and Range province. Chemical and fluid inclusion data demonstrate that production is from a narrow, asymmetric plume of thermal water that originates from a deep reservoir to the south and then flows laterally to the north. Geologic controls on the geometry of the upwelling plume were investigated using petrographic and analytical analyses of reservoir rock and vein material.
Curved mesh generation and mesh refinement using Lagrangian solid mechanics
Nonlinear continuum mechanics for ?nite element analysis,nement using Lagrangian Solid Mechanics Per-Olof Persson ?methods for computational mechanics has been emphasized in
Persson, P.-O.
X-ray peak broadening analysis of AA 6061{sub 100-x} - x wt.% Al{sub 2}O{sub 3} nanocomposite prepared by mechanical alloying
Nanocrystalline AA 6061 alloy reinforced with alumina (0, 4, 8, and 12 wt.%) in amorphized state composite powder was synthesized by mechanical alloying and consolidated by conventional powder metallurgy route. The as-milled and as-sintered (573 K and 673 K) nanocomposites were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The peaks corresponding to fine alumina was not observed by XRD patterns due to amorphization. Using high-resolution transmission electron microscope, it is confirmed that the presence of amorphized alumina observed in Al lattice fringes. The crystallite size, lattice strain, deformation stress, and strain energy density of AA 6061 matrix were determined precisely from the first five most intensive reflection of XRD using simple Williamson-Hall models; uniform deformation model, uniform stress deformation model, and uniform energy density deformation model. Among the developed models, uniform energy density deformation model was observed to be the best fit and realistic model for mechanically alloyed powders. This model evidenced the more anisotropic nature of the ball milled powders. The XRD peaks of as-milled powder samples demonstrated a considerable broadening with percentage of reinforcement due to grain refinement and lattice distortions during same milling time (40 h). The as-sintered (673 K) unreinforced AA 6061 matrix crystallite size from well fitted uniform energy density deformation model was 98 nm. The as-milled and as-sintered (673 K) nanocrystallite matrix sizes for 12 wt.% Al{sub 2}O{sub 3} well fitted by uniform energy density deformation model were 38 nm and 77 nm respectively, which indicate that the fine Al{sub 2}O{sub 3} pinned the matrix grain boundary and prevented the grain growth during sintering. Finally, the lattice parameter of Al matrix in as-milled and as-sintered conditions was also investigated in this paper. Research highlights: {yields} Integral breadth methods using various Williamson-Hall models were investigated for line profile analysis. {yields} Uniform energy density deformation model is observed to the best realistic model. {yields} The present analysis is used for understanding the stress and the strain present in the nanocomposites.
Sivasankaran, S., E-mail: firstname.lastname@example.com [Department of Production Engineering, National Institute of Technology, Tiruchirappalli-620015 (India); Sivaprasad, K., E-mail: email@example.com [Department of Metallurgical and Materials Engineering, National Institute of Technology, Tiruchirappalli-620 015 (India); Narayanasamy, R., E-mail: firstname.lastname@example.com [Department of Production Engineering, National Institute of Technology, Tiruchirappalli-620015 (India); Satyanarayana, P.V., E-mail: email@example.com [Powder Metallurgy Shop, Heavy Alloy Penetrator Project, Tiruchirappalli-620 025 (India)
Rock Physics of Geologic Carbon Sequestration/Storage
This report covers the results of developing the rock physics theory of the effects of CO{sub 2} injection and storage in a host reservoir on the rock?s elastic properties and the resulting seismic signatures (reflections) observed during sequestration and storage. Specific topics addressed are: (a) how the elastic properties and attenuation vary versus CO{sub 2} saturation in the reservoir during injection and subsequent distribution of CO{sub 2} in the reservoir; (b) what are the combined effects of saturation and pore pressure on the elastic properties; and (c) what are the combined effects of saturation and rock fabric alteration on the elastic properties. The main new results are (a) development and application of the capillary pressure equilibrium theory to forecasting the elastic properties as a function of CO{sub 2} saturation; (b) a new method of applying this theory to well data; and (c) combining this theory with other effects of CO{sub 2} injection on the rock frame, including the effects of pore pressure and rock fabric alteration. An important result is translating these elastic changes into synthetic seismic responses, specifically, the amplitude-versus-offset (AVO) response depending on saturation as well as reservoir and seal type. As planned, three graduate students participated in this work and, as a result, received scientific and technical training required should they choose to work in the area of monitoring and quantifying CO{sub 2} sequestration.
Dvorkin, Jack; Mavko, Gary
Mimbres rock art: a graphic legacy of cultural expression
Rock art abounds along the Mimbres River banks and drainage tributaries reflecting the rich cultural remains of the ancient Mimbres people. The Mimbres are a well established cultural group who lived in southwest New Mexico and northern Mexico from A.D. 200 and A.D. 1150. Physical remains of pithouses, pueblos, irrigation systems, artifacts, and rock art have survived the years to provide clues for contemporary understanding of this prehistoric culture and society. Knowledge of the symbolism and belief system has eluded understanding or remained sketchy as a result of examining only physical remains. Based on the hypothesis that by studying the archaeological record and the established characteristics of cultures with origins similar to those of the Mimbres, then assumptions can be made and applied to the understanding of the symbolism, purpose, and use of the rock art for the Mimbres. Specific to this study is the rock art adjacent to and within a one and one-half mile radius of the NAN Ranch Ruin. Research reveals how the rock art of the NAN Ranch Ruin connects to: 1) cultural context to other regional systems, 2) spatial context within the landscape, 3) temporal context with respect to Mimbres development, and 4) symbolic context, tying the rock art to its environment and revealing it as a living part of the universe as it fits into the world view of those who created it.
Tidemann, Kathryn
Location, age, and rock type of volcanic rocks younger than 5 million years in Arizona and New Mexico
As part of the assessment of the Hot Dry Rock geothermal energy potential of Arizona and New Mexico, a compilation of the locations and ages of volcanic rocks less than 5 Myr was made. The locations of those rocks less than 3 Myr are shown on a map of the region. Because the compiled information has many uses in addition to geothermal exploration, the entire compilation is presented as a tabulation. The table is organized first by state and secondly by latitude and longitude within each state. Rock type, age and error, method of dating, and original reference are also given. The K-Ar dates have not been recalculated using the most recent decay constants for /sup 40/K. A few references gave only verbal descriptions of sample location; these locations were converted to approximate latitude and longitude.
Aldrich, M.J. Jr.; Laughlin, A.W.
Laser-Mechanical Drilling for Geothermal Energy: Low-Contact Drilling Technology to Enable Economical EGS Wells
Broad Funding Opportunity Announcement Project: Foro Energy is developing a unique capability and hardware system to transmit high power lasers over long distances via fiber optic cables. This laser power is integrated with a mechanical drilling bit to enable rapid and sustained penetration of hard rock formations too costly to drill with mechanical drilling bits alone. The laser energy that is directed at the rock basically softens the rock, allowing the mechanical bit to more easily remove it. Foro Energy�s laser-assisted drill bits have the potential to be up to 10 times more economical than conventional hard-rock drilling technologies, making them an effective way to access the U.S. energy resources currently locked under hard rock formations.
Effect of Rock Transverse Isotropy on Stress Distribution and Wellbore Fracture
Unconventional oil and gas, which is of major interest in petroleum industry, often occur in reservoirs with transversely isotropic rock properties such as shales. Overlooking transverse isotropy may result in deviation in stress distribution around wellbore and inaccurate estimation of fracture initiation pressure which may jeopardize safe drilling and efficient fracturing treatment. In this work, to help understand the behavior of transversely isotropic reservoirs during drilling and fracturing, the principle of generalized plane-strain finite element formulation of anisotropic poroelastic problems is explained and a finite element model is developed from a plane-strain isotropic poroelastic model. Two numerical examples are simulated and the finite element results are compared with a closed form solution and another FE program. The validity of the developed finite element model is demonstrated. Using the validated finite element model, sensitivity analysis is carried out to evaluate the effects of transverse isotropy ratios, well azimuth, and rock bedding dip on pore pressure and stress distribution around a horizontal well. The results show that their effect cannot be neglected. The short term pore pressure distribution is sensitive to Young� modulus ratio, while the long term pore pressure distribution is only sensitive to permeability ratio. The total stress distribution generally is not sensitive to transverse isotropy ratios. The effective stress and fracture initiation are very sensitive to Young� modulus ratio. As the well rotates from minimum horizontal in-situ stress to maximum horizontal in-situ stress, the pore pressure and stress distributions tend to be more unevenly distributed around the wellbore, making the wellbore easier to fracture. The pore pressure and stress distributions tend to "rotate" in correspondence with the rock bedding plane. The fracture initiation potential and position will alter when rock bedding orientation varies.
Lu, Chunyang
Simulation of fluid-rock interactions in a geothermal basin. Final report. [QUAGMR (quasi-active geothermal reservoir)
General balance laws and constitutive relations are developed for convective hydrothermal geothermal reservoirs. A fully interacting rock-fluid system is considered; typical rock-fluid interactions involve momentum and energy transfer and the dependence of rock porosity and permeability upon the fluid and rock stresses. The mathematical model also includes multiphase (water/steam) effects. A simple analytical model is employed to study heat transfer into/or from a fluid moving in a porous medium. Numerical results show that for fluid velocities typical of geothermal systems (Reynolds number much less than 10), the fluid and the solid may be assumed to be in local thermal equilibrium. Mathematical formalism of Anderson and Jackson is utilized to derive a continuum species transport equation for flow in porous media; this method allows one to delineate, in a rigorous manner, the convective and diffusive mechanisms in the continuum representation of species transport. An existing computer program (QUAGMR) is applied to study upwelling of hot water from depth along a fault; the numerical results can be used to explain local temperature inversions occasionally observed in bore hole measurements.
Garg, S.K.; Blake, T.R.; Brownell, D.H. Jr.; Nayfeh, A.H.; Pritchett, J.W.
Simulation of CO2 Sequestration at Rock Spring Uplift, Wyoming: Heterogeneity and Uncertainties in Storage Capacity, Injectivity and Leakage
Many geological, geochemical, geomechanical and hydrogeological factors control CO{sub 2} storage in subsurface. Among them heterogeneity in saline aquifer can seriously influence design of injection wells, CO{sub 2} injection rate, CO{sub 2} plume migration, storage capacity, and potential leakage and risk assessment. This study applies indicator geostatistics, transition probability and Markov chain model at the Rock Springs Uplift, Wyoming generating facies-based heterogeneous fields for porosity and permeability in target saline aquifer (Pennsylvanian Weber sandstone) and surrounding rocks (Phosphoria, Madison and cap-rock Chugwater). A multiphase flow simulator FEHM is then used to model injection of CO{sub 2} into the target saline aquifer involving field-scale heterogeneity. The results reveal that (1) CO{sub 2} injection rates in different injection wells significantly change with local permeability distributions; (2) brine production rates in different pumping wells are also significantly impacted by the spatial heterogeneity in permeability; (3) liquid pressure evolution during and after CO{sub 2} injection in saline aquifer varies greatly for different realizations of random permeability fields, and this has potential important effects on hydraulic fracturing of the reservoir rock, reactivation of pre-existing faults and the integrity of the cap-rock; (4) CO{sub 2} storage capacity estimate for Rock Springs Uplift is 6614 {+-} 256 Mt at 95% confidence interval, which is about 36% of previous estimate based on homogeneous and isotropic storage formation; (5) density profiles show that the density of injected CO{sub 2} below 3 km is close to that of the ambient brine with given geothermal gradient and brine concentration, which indicates CO{sub 2} plume can sink to the deep before reaching thermal equilibrium with brine. Finally, we present uncertainty analysis of CO{sub 2} leakage into overlying formations due to heterogeneity in both the target saline aquifer and surrounding formations. This uncertainty in leakage will be used to feed into risk assessment modeling.
Deng, Hailin [Los Alamos National Laboratory; Dai, Zhenxue [Los Alamos National Laboratory; Jiao, Zunsheng [Wyoming State Geological Survey; Stauffer, Philip H. [Los Alamos National Laboratory; Surdam, Ronald C. [Wyoming State Geological Survey
Environmental assessment of remedial action at the slick rock Uranium Mill Tailings sites Slick Rock, Colorado
The Uranium Mill Tailings Radiation Control Act of 1978 (42 USC {section} 7901 et seq.), hereafter referred to as the UMTRCA, authorized the U.S. Department of Energy (DOE) to clean up two uranium mill tailings processing sites near Slick Rock, Colorado, in San Miguel County. The purpose of the cleanup is to reduce the potential health effects associated with the radioactive materials remaining on the sites and on vicinity properties (VPs) associated with the sites. Contaminated materials cover an estimated 55 acres of the Union Carbide (UC) processing site and 12 ac of the North Continent (NC) processing site. The total estimated volume of contaminated materials is approximately 61 8,300 cubic yards. In addition to the contamination in the two processing site areas, four VPs were found to contain contamination. As a result of the tailings being exposed to the environment, contamination associated with the UC and NC sites has leached into shallow ground water. Surface water has not been affected. The closest residence is approximately 0.3 air mi from either site. The proposed action is to remediate the UC and NC sites by removing all contaminated materials within the designated site boundaries or otherwise associated with the sites, and relocating them to, and stabilizing them at, a location approximately 5 road mi (8 km) northeast of the sites on land administered by the Bureau of Land Management (BLM). Remediation would be performed by the DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project. All solid contaminated materials would be buried under 5 feet (ft) of rock and soil materials. The proposed disposal site area is currently used by ranchers for cattle grazing over a 7-month period. The closest residence to the proposed disposal site is 2 air mi. An estimated 44 ac of land would be permanently transferred from the BLM to the DOE and restricted from future use.
Deriving the shape factor of a fractured rock matrix
Fluid flow from a fractured rock matrix was investigated for accurately predicting oil recovery from fractured reservoirs. To relate the oil rate with rock geometry and average rock matrix pressure, a shape factor is used in the mathematical model of fractured reservoirs. The shape factor in the transfer function was derived by solving the three-dimensional diffusivity equation of a rock matrix block under unsteady-state production, in contrast to the quasi-steady-state condition assumed by most previous studies denoted in the literature. The diffusivity equation in the x, y, and z coordinate was solved in four cases by assuming different boundary conditions of (1) constant fracture pressure; (2) constant flow rate; (3) constant fracture pressure followed by linearly declining fracture pressure; and (4) linearly declining fracture pressure followed by constant fracture pressure. Shape factor values are high at the initial depletion stage under an unsteady-state condition. When the fracture pressure is constant, the shape factor converges to {pi}{sup 2}/L{sup 2}, 2{pi}{sup 2}/L{sup 2}, and 3{pi}{sup 2}/L{sup 2} for one-, two-, and three-dimensional rock matrix, respectively, at the dimensionless time ({tau}) of about 0.1. When the flow rate between the rock matrix and the fracture is constant, the fracture pressure varies with location on the rock surface. Based on the average fracture pressure, the shape factor decreases with production time until a {tau} value of 0.1 is reached. The boundary conditions of constant fracture pressure followed by a constant decline in fracture pressure are equivalent to the condition of a constant fracture pressure followed by a period of constant flow rate.
Chang, Ming-Ming
Creep in the crust and mantle is commonly considered a steady-state process. This view prevails despite the fact that earthquakes do not represent steady-state and at the base of the seismogenic zone, for example, the stresses that drive creep must vary with the earthquake cycle. The contribution of transient versus steady-state behavior is not easy to determine from naturally-deformed brittle or plastic rocks and our view of steady-state depends on whether we consider geological or shorter time-scales. Perhaps we avoid a non steady-state picture because we lack appropriate descriptive or quantitative tools. The aim of the 2010 Gordon Research Conference (GRC) in rock deformation is to explore what we know about non steady-state deformation and how we might advance our understanding through geological and geophysical field investigations, laboratory experiments and modeling. This will require an appraisal of the applicability of steady-state concepts as well as an exploration of transient behavior, in which processes and physical properties cycle between different states as might be the case during earthquake cycles, and transitions in behavior, where finite strain or changing environmental conditions lead to changes in processes and properties. Conference sessions will cover seven broad and interlinked topics. (1) What is steady state?; an appraisal of applicability of the steady-state concept in rock deformation. (2) Seismogenic Faulting and Brittle Fault Rocks; where transience in rates and conditions are accepted but not fully understood. (3) Episodic Creep During the Seismic Cycle; with a focus on processes in areas adjacent to the base of the seismogenic zone. (4) Creep in Zones of Stress and Temperature Cycling; considering deformation in real-world complex systems (5) Deformation, Metamorphism, and Fluids; exploring the interaction of diagenesis/metamorphism and thermal instabilities with deformation. (6) Mechanism and Microstructure Transitions During Deformation; quantifying evolution as a function of strain and associated with changes in deformation kinematics or conditions. (7) Mechanism and Microstructure Transitions Related to Mantle Geophysics; with a focus on the link between mechanisms affecting processes on geological time-scales on the time-scales associated with seismic wave propagation. The GRC on Rock Deformation aims to bring together researchers with diverse expertise, and to shape the scientific debate and provide inspiration for young researchers to fill the still extensive gaps in our knowledge of how the Earth deforms. The processes that will be discussed have wide applications in both basic and applied research. A key issue, of fundamental importance to our understanding of the Earth, for discussion at this meeting will be the transition from time-dependent (and distributed) rock deformation, including both high temperature creep and brittle creep, to episodic (and more localized) events. Such transitions have both a scientific and a socio-economic impact since they control the precursory phases of important geohazards such as earthquake rupture and volcanic eruptions, and also influence effective recovery of hydrocarbon and geothermal energy resources, and the integrity of long-term storage facilities for hazardous waste.
David Prior
Diffusive separation of noble gases and noble gas abundance patterns in sedimentary rocks
The mechanisms responsible for noble gas concentrations, abundance patterns, and strong retentivity in sedimentary lithologies remain poorly explained. Diffusion-controlled fractionation of noble gases is modeled and examined as an explanation for the absolute and relative abundances of noble gases observed in sediments. Since the physical properties of the noble gases are strong functions of atomic mass, the individual diffusion coefficients, adsorption coefficients and atomic radii combine to impede heavy noble gas (Xe) diffusion relative to light noble gas (Ne) diffusion. Filling of lithic grains/half-spaces by diffusive processes thus produces Ne enrichments in the early and middle stages of the filling process with F(Ne) values similar to that observed in volcanic glasses. Emptying lithic grains/half-spaces produces a Xe-enriched residual in the late (but not final) stages of the process producing F(Xe) values similar to that observed in shales. 'Exotic but unexceptional' shales that exhibit both F(Ne) and F(Xe) enrichments can be produced by incomplete emptying followed by incomplete filling. This mechanism is consistent with literature reported noble gas abundance patterns but may still require a separate mechanism for strong retention. A system of labyrinths-with-constrictions and/or C-, Si-nanotubes when combined with simple adsorption can result in stronger diffusive separation and non-steady-state enrichments that persist for longer times. Enhanced adsorption to multiple C atoms inside C-nanotubes as well as dangling functional groups closing the ends of nanotubes can provide potential mechanisms for 'strong retention'. We need new methods of examining noble gases in rocks to determine the role and function of angstrom-scale structures in both the diffusive enrichment process and the 'strong retention' process for noble gas abundances in terrestrial rocks.
Torgersen, T.; Kennedy, B.M.; van Soest, M.C.
Adsorption of water vapor on reservoir rocks. First quarterly report, January--March 1993
PARKER-HEADGATE ROCK & PARKER-GILA PARKER-HEADGATE ROCK & PARKER-GILA 161-kV TRANSMISSION LINE Cross Arm Repair and Helicopter Staging Areas Figure 1. Project Location Project Location j PARKER-HEADGATE ROCK & PARKER-GILA 161-kV TRANSMISSION LINE Cross Arm Repair and Helicopter Staging Areas Figure 2a. Project Area (North) Staging Area #4 Structure 3/5 Structure 3/6 Structure 3/4 Structure 3/7 Structure 3/5 Structure 3/6 PARKER-HEADGATE ROCK 161-kV TRANSMISSION LINE PARKER-GILA 161-kV TRANSMISSION LINE Structure 4/6 Legal Description N N 1:24000 scale 1:24000 scale Section Township Range 17 20 2 N 27 E 31 11 N 18 W 6 10 N USGS TOPO MAP: Cross Roads, Arizona-California USGS TOPO MAP: Cross Roads, Arizona-California PARKER-HEADGATE ROCK & PARKER-GILA 161-kV TRANSMISSION LINE Cross Arm Repair and Helicopter Staging Areas
Energy extraction characteristics of hot dry rock geothermal systems
The LASL Hot Dry Rock Geothermal Energy Project is investigating methods to extract energy at useful temperatures and rates from naturally heated crustal rock in locations where the rock does not spontaneously yield natural steam or hot water at a rate sufficient to support commercial utilization. Several concepts are discussed for application to low and high permeability formations. The method being investigated first is intended for use in formations of low initial permeability. It involves producing a circulation system within the hot rock by hydraulic fracturing to create a large crack connecting two drilled holes, then operating the system as a closed pressurized-water heat-extration loop. With the best input assumptions that present knowledge provides, the fluid-flow and heat-exchange calculations indicate that unpumped (buoyant) circulation through a large hydraulic fracture can maintain a commercially useful rate of heat extraction throughout a usefully long system life. With a power cycle designed for the temperature of the fluid produced, total capital investment and generating costs are estimated to be at least competitive with those of fossil-fuel-fired and nuclear electric plants. This paper discusses the potential of the hot dry rock resource, various heat extraction concepts, prediction of reservoir performance, and economic factors, and summarizes recent progress in the LASL field program.
Tester, J.W.; Smith, M.C.
Los Alamos hot dry rock geothermal energy experiment
Recent heat flow data indicates that about 95,000 sq. mi. in 13 western U.S. states is underlain, at a depth of 5 km (16,400 ft) by hot dry rock at temperatures above 290/sup 0/C (440/sup 0/F.). Therefore a geothermal energy development program was undertaken to develop methods from extracting thermal energy from hot rock in the earth crust by man-made underground circulation systems; demonstrate the commercial feasibility of such systems; and encourage use of this technology. Experiments performed on the Jemez Plateau in New Mexico are described with information on the drilling of boreholes, hydraulic fracturing of hot rocks, well logging, and environmental monitoring to establish base line data and define the potential effects of the project. The technical achievements of the project include boreholes were drilled to 3k (10,000 ft) with bottomhole temperatures of approximately 200/sup 0/C (390/sup 0/F); hydraulic fracturing produced fractured regions with 150 m (500 ft) radii; at least 90 percent of the water injected was recovered; and data was obtained on geologic conditions, seismic effects, and thermal, fracturing, and chemical properties of the downhole rocks. A geothermal power-production system model was formulated for evaluating the total cost of developing power production using a hot-dry-rock geothermal energy source. (LCL)
Pettitt, R.A.
The Effect of Heterogeneity on Matrix Acidizing of Carbonate Rocks
In matrix acidizing, the goal is to dissolve minerals in the rock to increase well productivity. This is accomplished by injecting an application-specific solution of acid into the formation at a pressure between the pore pressure and fracture pressure. A hydrochloric acid solution is used in carbonate reservoirs, which actually dissolves the calcite rock matrix in the form of conductive channels called wormholes. These wormholes propagate from the wellbore out into the reservoir, bypassing the damaged zone. In matrix acidizing of carbonates, there are four parameters that affect performance: the concentration of calcite present, injection rate of the acid, reaction type, and heterogeneity. Of these parameters, this paper will focus on how rock heterogeneity affects performance. To do this, a coreflood and acidizing apparatus was used to acidize heterogeneous limestone core samples. Rock characterizations and volumetric measurements were considered with the results from these experiments, which made it possible to correlate and quantify the results with rock and volume parameters. It was found that the core samples with more and larger heterogeneities generally required less acid (measured in pore volumes) to achieve breakthrough, that is, a wormhole created axially from one end of the core to the other. This value for pore volumes to breakthrough was one to two orders of magnitude less than more homogeneous samples. The general procedure and best practices for acidizing the core samples is also detailed in this thesis. This procedure was followed for preparation, coreflooding, and acidizing for all core samples.
Keys, Ryan S.
Proceedings of the scientific visit on crystalline rock repository development.
A scientific visit on Crystalline Rock Repository Development was held in the Czech Republic on September 24-27, 2012. The visit was hosted by the Czech Radioactive Waste Repository Authority (RAWRA), co-hosted by Sandia National Laboratories (SNL), and supported by the International Atomic Energy Agency (IAEA). The purpose of the visit was to promote technical information exchange between participants from countries engaged in the investigation and exploration of crystalline rock for the eventual construction of nuclear waste repositories. The visit was designed especially for participants of countries that have recently commenced (or recommenced) national repository programmes in crystalline host rock formations. Discussion topics included repository programme development, site screening and selection, site characterization, disposal concepts in crystalline host rock, regulatory frameworks, and safety assessment methodology. Interest was surveyed in establishing a %E2%80%9Cclub,%E2%80%9D the mission of which would be to identify and address the various technical challenges that confront the disposal of radioactive waste in crystalline rock environments. The idea of a second scientific visit to be held one year later in another host country received popular support. The visit concluded with a trip to the countryside south of Prague where participants were treated to a tour of the laboratory and underground facilities of the Josef Regional Underground Research Centre.
Mariner, Paul E.; Hardin, Ernest L.; Miksova, Jitka [RAWRA, Czech Republic
Transient Thermal, Hydraulic, and Mechanical Analysis of a Counter Flow Offset Strip Fin Intermediate Heat Exchanger using an Effective Porous Media Approach.
??This work presents a comprehensive thermal hydraulic analysis of a compact heat exchanger using offset strip fins. The thermal hydraulics analysis in this work is� (more)
Mining engineering analysis
An attempt is made to fill the gap between theory and application in mining engineering. The book is based on SME Mining Engineering Handbook and the Coal Mining Technology - Theory and Practice. Each chapter deals with the theory and then presents problems of applications and the solutions to them. Topics considered include underground mining, surface mining, geophysics, mining equipment, and rock mechanics.
Bise, C.J.
Black Rock III Geothermal Project | Open Energy Information
Black Rock III Geothermal Project Black Rock III Geothermal Project Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Development Project: Black Rock III Geothermal Project Project Location Information Coordinates The following coordinate was not recognized: 33°19'59" N, 115°50'3 W.The following coordinate was not recognized: 33°19'59" N, 115°50'3 W. Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[]}
3rd Rock Systems and Technologies | Open Energy Information
Rock Systems and Technologies Rock Systems and Technologies Jump to: navigation, search Name 3rd Rock Systems and Technologies Place Burlingame, California Zip 94010 Sector Renewable Energy, Services Product Provides proven renewable energy technologies and consulting services to residential, commercial, and industrial clients. Coordinates 38.753055°, -95.834619° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.753055,"lon":-95.834619,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
AltaRock Energy Inc | Open Energy Information
AltaRock Energy Inc AltaRock Energy Inc Jump to: navigation, search Name AltaRock Energy Address 7900 E Green Lake Drive N Place Seattle, Washington Zip 98103 Sector Geothermal energy Product Creates geothermal energy reservoirs, develops geothermal facilities Website http://www.altarockenergy.com/ Coordinates 47.6855466°, -122.3364827° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":47.6855466,"lon":-122.3364827,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Chimney Rock Public Power Dist | Open Energy Information
Chimney Rock Public Power Dist Chimney Rock Public Power Dist Jump to: navigation, search Name Chimney Rock Public Power Dist Place Nebraska Utility Id 3495 Utility Location Yes Ownership P NERC Location MRO NERC MRO Yes Activity Distribution Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png ELECTRIC THERMAL STORAGE Commercial GENERAL SEASONAL Commercial IRRIGATION SERVICE Single Phase Commercial IRRIGATION SERVICE Three Phase Commercial IRRIGATION STANDBY RATE, Single Phase Commercial IRRIGATION STANDBY RATE, Three Phase Commercial LARGE POWER SERVICE Commercial RESIDENTIAL SERVICE AND SEASONAL SERVICE Residential
City of Rock Hill, South Carolina (Utility Company) | Open Energy
Rock Hill, South Carolina (Utility Company) Rock Hill, South Carolina (Utility Company) Jump to: navigation, search Name City of Rock Hill Place South Carolina Utility Id 16195 Utility Location Yes Ownership M NERC Location SERC Activity Bundled Services Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png 175 Watt HPS lighting Lighting Economic Development Rate (Schedule EDR -1) Commercial Economic Development Rate (Schedule EDR -2) Industrial Flood Lighting Rate 1000 Watt HPS Lighting Flood Lighting Rate 400 Watt HPS Lighting General Service/ Non Demand (Schedule GS) Commercial General Service/Demand (Schedule GD) Industrial
Supercritical Carbon Dioxide / Reservoir Rock Chemical Interactions | Open
Supercritical Carbon Dioxide / Reservoir Rock Chemical Interactions Supercritical Carbon Dioxide / Reservoir Rock Chemical Interactions Jump to: navigation, search Geothermal Lab Call Projects for Supercritical Carbon Dioxide / Reservoir Rock Chemical Interactions Loading map... {"format":"googlemaps3","type":"ROADMAP","types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"limit":200,"offset":0,"link":"all","sort":[""],"order":[],"headers":"show","mainlabel":"","intro":"","outro":"","searchlabel":"\u2026 further results","default":"","geoservice":"google","zoom":false,"width":"600px","height":"350px","centre":false,"layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","icon":"","visitedicon":"","forceshow":true,"showtitle":true,"hidenamespace":false,"template":false,"title":"","label":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"locations":[{"text":"
Search for magnetic monopoles in polar volcanic rocks
For a broad range of values of magnetic monopole mass and charge, the abundance of monopoles trapped inside the Earth would be expected to be enhanced in the mantle beneath the geomagnetic poles. A search for magnetic monopoles was conducted using the signature of an induced persistent current following the passage of igneous rock samples through a SQUID-based magnetometer. A total of 24.6 kg of rocks from various selected sites, among which 23.4 kg are mantle-derived rocks from the Arctic and Antarctic areas, was analysed. No monopoles were found and a 90% confidence level upper limit of $9.8\\cdot 10^{-5}$/gram is set on the monopole density in the search samples.
K. Bendtz; D. Milstead; H. -P. H�chler; A. M. Hirt; P. Mermod; P. Michael; T. Sloan; C. Tegner; S. B. Thorarinsson
Alternate operating strategies for Hot Dry Rock geothermal reservoirs
Flow testing and heat extraction experiments in prototype Hot Dry Rock (HDR) geothermal reservoirs have uncovered several challenges which must be addressed before commercialization of the technology is possible. Foremost among these is the creation of a reservoir which simultaneously possesses high permeability pathways and a large volume of fractured rock. The current concept of heat extraction -- a steady state circulation system with fluid pumping from the injection well to a single, low pressure production well -- may limit our ability to create heat extraction systems which meet these goals. A single injection well feeding two production wells producing fluid at moderate pressures is shown to be a potentially superior way to extract heat. Cyclic production is also demonstrated to have potential as a method for sweeping fluid through a larger volume of rock, thereby inhibiting flow channeling and increasing reservoir lifetime. 10 refs., 4 figs., 2 tabs.
Robinson, B.A.
Application of real rock pore-threat statistics to a regular pore network model
This work reports the application of real rock statistical data to a previously developed regular pore network model in an attempt to produce an accurate simulation tool with low computational overhead. A core plug from the St. Peter Sandstone formation in Indiana was scanned with a high resolution micro CT scanner. The pore-throat statistics of the three-dimensional reconstructed rock were extracted and the distribution of the pore-throat sizes was applied to the regular pore network model. In order to keep the equivalent model regular, only the throat area or the throat radius was varied. Ten realizations of randomly distributed throat sizes were generated to simulate the drainage process and relative permeability was calculated and compared with the experimentally determined values of the original rock sample. The numerical and experimental procedures are explained in detail and the performance of the model in relation to the experimental data is discussed and analyzed. Petrophysical properties such as relative permeability are important in many applied fields such as production of petroleum fluids, enhanced oil recovery, carbon dioxide sequestration, ground water flow, etc. Relative permeability data are used for a wide range of conventional reservoir engineering calculations and in numerical reservoir simulation. Two-phase oil water relative permeability data are generated on the same core plug from both pore network model and experimental procedure. The shape and size of the relative permeability curves were compared and analyzed and good match has been observed for wetting phase relative permeability but for non-wetting phase, simulation results were found to be deviated from the experimental ones. Efforts to determine petrophysical properties of rocks using numerical techniques are to eliminate the necessity of regular core analysis, which can be time consuming and expensive. So a numerical technique is expected to be fast and to produce reliable results. In applied engineering, sometimes quick result with reasonable accuracy is acceptable than the more time consuming results. Present work is an effort to check the accuracy and validity of a previously developed pore network model for obtaining important petrophysical properties of rocks based on cutting-sized sample data.
Rakibul, M.; Sarker, H.; McIntyre, D.; Ferer, M.; Siddiqui, S.; Bromhal. G.
Application of real rock pore-throat statistics to a regular pore network model
This work reports the application of real rock statistical data to a previously developed regular pore network model in an attempt to produce an accurate simulation tool with low computational overhead. A core plug from the St. Peter Sandstone formation in Indiana was scanned with a high resolution micro CT scanner. The pore-throat statistics of the three-dimensional reconstructed rock were extracted and the distribution of the pore-throat sizes was applied to the regular pore network model. In order to keep the equivalent model regular, only the throat area or the throat radius was varied. Ten realizations of randomly distributed throat sizes were generated to simulate the drainage process and relative permeability was calculated and compared with the experimentally determined values of the original rock sample. The numerical and experimental procedures are explained in detail and the performance of the model in relation to the experimental data is discussed and analyzed. Petrophysical properties such as relative permeability are important in many applied fields such as production of petroleum fluids, enhanced oil recovery, carbon dioxide sequestration, ground water flow, etc. Relative permeability data are used for a wide range of conventional reservoir engineering calculations and in numerical reservoir simulation. Two-phase oil water relative permeability data are generated on the same core plug from both pore network model and experimental procedure. The shape and size of the relative permeability curves were compared and analyzed and good match has been observed for wetting phase relative permeability but for non-wetting phase, simulation results were found to be deviated from the experimental ones. Efforts to determine petrophysical properties of rocks using numerical techniques are to eliminate the necessity of regular core analysis, which can be time consuming and expensive. So a numerical technique is expected to be fast and to produce reliable results. In applied engineering, sometimes quick result with reasonable accuracy is acceptable than the more time consuming results. Present work is an effort to check the accuracy and validity of a previously developed pore network model for obtaining important petrophysical properties of rocks based on cutting-sized sample data. Introduction
Sarker, M.R.; McIntyre, D.; Ferer, M.; Siddigui, S.; Bromhal. G.
Microfractures in rocks from two geothermal areas | Open Energy Information
source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Microfractures in rocks from two geothermal areas Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Microfractures in rocks from two geothermal areas Details Activities (2) Areas (2) Regions (0) Abstract: Core samples from the Dunes, California, and Raft River, Idaho, geothermal areas show diagenesis superimposed on episodic fracturing and fracture sealing. The minerals that fill fractures show significant temporal variations. Sealed fractures can act as barriers to fluid flow. Sealed fractures often mark boundaries between regions of significantly
Los Alamos hot-dry-rock project: recent results
A new deeper reservoir is presently being investigated at the Laboratory's Fenton Hill Hot Dry Rock (HDR) site. The region surrounding the lower of two inclined boreholes, directionally-drilled to about 4 km in hot crystalline rock, has been pressurized in a sequence of injection tests. Based primarily on the measurements made by two close-in microseismic detectors, two similar volumetric reservoir regions have been developed by massive hydraulic fracturing, but with no significant hydraulic communication with the upper borehole as yet.
As part of our study on ''Relationships between seismic properties and rock microstructure'', we have (1) Studied relationships between velocity and permeability. (2) Used independent experimental methods to measure the elastic moduli of clay minerals as functions of pressure and saturation. (3) Applied different statistical methods for characterizing heterogeneity and textures from scanning acoustic microscope (SAM) images of shale microstructures. (4) Analyzed the directional dependence of velocity and attenuation in different reservoir rocks (5) Compared Vp measured under hydrostatic and non-hydrostatic stress conditions in sands. (6) Studied stratification as a source of intrinsic anisotropy in sediments using Vp and statistical methods for characterizing textures in sands.
Ozone generation by rock fracture: Earthquake early warning?
We report the production of up to 10 ppm ozone during crushing and grinding of typical terrestrial crust rocks in air, O{sub 2} and CO{sub 2} at atmospheric pressure, but not in helium or nitrogen. Ozone is formed by exoelectrons emitted by high electric fields, resulting from charge separation during fracture. The results suggest that ground level ozone produced by rock fracture, besides its potential health hazard, can be used for early warning in earthquakes and other catastrophes, such as landslides or land shifts in excavation tunnels and underground mines.
Baragiola, Raul A.; Dukes, Catherine A.; Hedges, Dawn [Engineering Physics, University of Virginia, Charlottesville, Virginia 22904 (United States)
Petrography Analysis | Open Energy Information
Petrography Analysis Petrography Analysis Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Petrography Analysis Details Activities (6) Areas (5) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Provides detailed information about rock composition and morphology Stratigraphic/Structural: Hydrological: Thermal: Cost Information Low-End Estimate (USD): 275.0027,500 centUSD 0.275 kUSD 2.75e-4 MUSD 2.75e-7 TUSD / sample Median Estimate (USD): 420.0042,000 centUSD 0.42 kUSD 4.2e-4 MUSD 4.2e-7 TUSD / sample High-End Estimate (USD): 625.0062,500 centUSD 0.625 kUSD 6.25e-4 MUSD 6.25e-7 TUSD / sample
Topics covered include: Failure At High Confining Pressure; Fluid-assisted Slip, Earthquakes & Fracture; Reaction-driven Cracking; Fluid Transport, Deformation And Reaction; Localized Fluid Transport And Deformation; Earthquake Mechanisms; Subduction Zone Dynamics And Crustal Growth.
Kelemen, Peter
Hot Dry Rock Geothermal Energy Development Program. Annual report, fiscal year 1979
The Fenton Hill Project is still the principal center for developing methods, equipment, and instrumentation for creating and utilizing HDR geothermal reservoirs. The search for a second site for a similar experimental system in a different geological environment has been intensified, as have the identification and characterization of other HDR areas that may prove suitable for either experimental or commercial development. The Phase I fracture system was enlarged during FY79. Drilling of the injection well of the Phase II system began at Fenton Hill in April 1979. Environmental monitoring of the Fenton Hill area continued through FY79. The environmental studies indicate that the hot dry rock operations have caused no significant environmental impact. Other supporting activities included rock physics, rock mechanics, fracture mapping, and instrumentation development. Two closely related activities - evaluation of the potential HDR energy resource of the US and the selection of a site for development of a second experimental heat-extraction system generally similar to that at Fenton Hill - have resulted in the collection of geology, hydrology, and heat-flow data on some level of field activity in 30 states. The resource-evaluation activity included reconnaissance field studies and a listing and preliminary characterization of US geothermal areas in which HDR energy extraction methods may be applicable. The selection of Site 2 has taken into account such legal, institutional, and economic factors as land ownership and use, proximity to possible users, permitting and licensing requirements and procedures, environmental issues, areal extent of the geothermal area, and visibility to and apparent interest by potential industrial developers.
Cremer, G.M.; Duffield, R.B.; Smith, M.C.; Wilson, M.G. (comps.)
Effects of burial history, rock ductility and recovery magnitude on inversion of normal faulted strata
Inversion of normal faults at different burial depths is studied using physical models constructed with rock and deformed at confining pressure. Models consist of a 1 cm thick limestone layer above a fault dipping 70� in a rigid medium, and are subjected to a two-stage deformation path of layer-parallel extension followed by coaxial contraction. To investigate the effects of burial depth and relative ductility on kinematics of inversion, five model suites were run in which confining pressure and recovery magnitudes were varied. In all models, a normal fault forms in the limestone during extension. Subsequent inversion is accommodated in the limestone by reverse slip on the normal fault, creation and movement along new reverse faults, and distributed fracturing and folding. The relative contribution of these mechanisms depends on the relative ductility of the rock and magnitude of inversion. Reverse slip on the normal fault and distributed fracturing occur during early stages of inversion and new reverse faults form at intermediate stages. During late stage inversion, strata with low mean ductility shorten primarily by reverse slip on the pre-existing normal fault, whereas strata with high mean ductility shorten by continued slip on reverse faults. Evidence for inversion is provided by superposed fracture fabrics in the footwall at early stages (100% recovery). This change in fracture fabric during inversion could lead to an overpressured footwall in natural inversion structures. Reverse reactivation of the normal faults may occur during coaxial contraction even though such faults are unfavorably oriented assuming typical rock friction behavior and a homogeneous stress state. Localized reverse slip on normal faults is favored when strata display low ductility and less favored when strata work-harden during extension, however, the models show that the final inversion geometry is dependent on the ductility during both phases of deformation. Even a fault that is work-hardened during extension can reactivate if the ductility during contraction is low enough.
Kuhle, Nathan John
Carlsson, H. , "Hydraulic fracturing and overcoring stress1949). Haimson, B.C. , "Hydraulic fracturing in porous andc.B. , "Laboratory hydraulic fracturing experiments in
Ratigan, J.L.
Solar �panels �and �stations �were �dug �out �after �storm �storm � cycles � with � a � reasonably � small � and � portable � solar �storm � cycle, � and � a � five-�?day � period � in � May � when � the � solar �
efficiency � (10%), � losses � (20%) � and � peak � power � point � (17 �V) �results �in �a �minimum �requirement �of �a �30-�?watt �solar �panel. � �
KBS): "Handling of Spent Nuclear Fuel and Final Storage ofionwith the Swedish Nuclear Fuel Supply Company. REFERENCESReport of ctltdy Group on Nuclear Fuel Cycles and Waste
Cook, N.G.W.; Witherspoon, P.A.
noise � events � and � thus, � trigger. � � Three �This � event � and � the � other � triggers � not �did �not � trigger �on �known �events �were �reviewed �
Thesis A Numerical Model of Hydro-Thermo- Mechanical Coupling...
1 31 53-T Thesis A Numerical Model of Hydro-Thermo- Mechanical Coupling in a Fractured Rock Mass ECEIVED Los Alamos N A T I O N A L L A B O R A T O R Y Los Alamos National...
Environmental assessment of remedial action at the Slick Rock uranium mill tailings sites, Slick Rock, Colorado
The Uranium Mill Tailings Radiation Control Act of 1978, hereafter referred to as the UMTRCA, authorized the US Department of Energy (DOE) to clean up two uranium mill tailings processing sites near Slick Rock, Colorado, in San Miguel County. The purpose of the cleanup is to reduce the potential health effects associated with the radioactive materials remaining on the processing sites and on vicinity properties (VPs) associated with the sites. The US Environmental Protection Agency (EPA) promulgated standards for the UMTRCA that contained measures to control the contaminated materials and to protect the ground water from further degradation. The sites contain concrete foundations of mill buildings, tailings piles, and areas contaminated by windblown and waterborne radioactive tailings materials. The proposed action is to remediate the UC and NC sites by removing all contaminated materials within the designated site boundaries or otherwise associated with the sites, and relocating them to, and stabilizing them at, a location approximately 5 road mi (8 km) northeast of the processing sites on land administered by the US Bureau of Land Management (BLM). Remediation would be performed by the DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project.
Hot dry rock energy: Hot dry rock geothermal development program. Progress report. Fiscal year 1993
Extended flow testing at the Fenton Hill Hot Dry Rock (HDR) test facility concluded in Fiscal Year 1993 with the completion of Phase 2 of the long-term flow test (LTFT) program. As is reported in detail in this report, the second phase of the LTFT, although only 55 days in duration, confirmed in every way the encouraging test results of the 112-day Phase I LTFT carried out in Fiscal Year 1992. Interim flow testing was conducted early in FY 1993 during the period between the two LTFT segments. In addition, two brief tests involving operation of the reservoir on a cyclic schedule were run at the end of the Phase 2 LTFT. These interim and cyclic tests provided an opportunity to conduct evaluations and field demonstrations of several reservoir engineering concepts that can now be applied to significantly increase the productivity of HDR systems. The Fenton Hill HDR test facility was shut down and brought into standby status during the last part of FY 1993. Unfortunately, the world`s largest, deepest, and most productive HDR reservoir has gone essentially unused since that time.
Salazar, J.; Brown, M. [eds.
Fluid-rock interaction: A reactive transport approach
Fluid-rock interaction (or water-rock interaction, as it was more commonly known) is a subject that has evolved considerably in its scope over the years. Initially its focus was primarily on interactions between subsurface fluids of various temperatures and mostly crystalline rocks, but the scope has broadened now to include fluid interaction with all forms of subsurface materials, whether they are unconsolidated or crystalline ('fluid-solid interaction' is perhaps less euphonious). Disciplines that previously carried their own distinct names, for example, basin diagenesis, early diagenesis, metamorphic petrology, reactive contaminant transport, chemical weathering, are now considered to fall under the broader rubric of fluid-rock interaction, although certainly some of the key research questions differ depending on the environment considered. Beyond the broadening of the environments considered in the study of fluid-rock interaction, the discipline has evolved in perhaps an even more important way. The study of water-rock interaction began by focusing on geochemical interactions in the absence of transport processes, although a few notable exceptions exist (Thompson 1959; Weare et al. 1976). Moreover, these analyses began by adopting a primarily thermodynamic approach, with the implicit or explicit assumption of equilibrium between the fluid and rock. As a result, these early models were fundamentally static rather than dynamic in nature. This all changed with the seminal papers by Helgeson and his co-workers (Helgeson 1968; Helgeson et al. 1969) wherein the concept of an irreversible reaction path was formally introduced into the geochemical literature. In addition to treating the reaction network as a dynamically evolving system, the Helgeson studies introduced an approach that allowed for the consideration of a multicomponent geochemical system, with multiple minerals and species appearing as both reactants and products, at least one of which could be irreversible. Helgeson's pioneering approach was given a more formal kinetic basis (including the introduction of real time rather than reaction progress as the independent variable) in subsequent studies (Lasaga 1981; Aagaard and Helgeson 1982; Lasaga 1984). The reaction path approach can be used to describe chemical processes in a batch or closed system (e.g., a laboratory beaker), but such systems are of limited interest in the Earth sciences where the driving force for most reactions is transport. Lichtner (1988) clarified the application of the reaction path models to water-rock interaction involving transport by demonstrating that they could be used to describe pure advective transport through porous media. By adopting a reference frame which followed the fluid packet as it moved through the medium, the reaction progress variable could be thought of as travel time instead. Multi-component reactive transport models that could treat any combination of transport and biogeochemical processes date back to the early 1980s. Berner and his students applied continuum reactive transport models to describe processes taking place during the early diagenesis of marine sediments (Berner 1980). Lichtner (1985) outlined much of the basic theory for a continuum model for multicomponent reactive transport. Yeh and Tripathi (1989) also presented the theoretical and numerical basis for the treatment of reactive contaminant transport. Steefel and Lasaga (1994) presented a reactive flow and transport model for nonisothermal, kinetically-controlled water-rock interaction and fracture sealing in hydrothermal systems based on simultaneous numerical solution of both reaction and transport This chapter begins with a review of the important transport processes that affect or even control fluid-rock interaction. This is followed by a general introduction to the governing equations for reactive transport, which are broadly applicable to both qualitative and quantitative interpretations of fluid-rock interactions. This framework is expanded through a discussion of specific topics that are the f
Steefel, C.; Maher, K.
Thermal-Hydrological Sensitivity Analysis of Underground Coal Gasification
This paper presents recent work from an ongoing project at Lawrence Livermore National Laboratory (LLNL) to develop a set of predictive tools for cavity/combustion-zone growth and to gain quantitative understanding of the processes and conditions (natural and engineered) affecting underground coal gasification (UCG). We discuss the application of coupled thermal-hydrologic simulation capabilities required for predicting UCG cavity growth, as well as for predicting potential environmental consequences of UCG operations. Simulation of UCG cavity evolution involves coupled thermal-hydrological-chemical-mechanical (THCM) processes in the host coal and adjoining rockmass (cap and bedrock). To represent these processes, the NUFT (Nonisothermal Unsaturated-saturated Flow and Transport) code is being customized to address the influence of coal combustion on the heating of the host coal and adjoining rock mass, and the resulting thermal-hydrological response in the host coal/rock. As described in a companion paper (Morris et al. 2009), the ability to model the influence of mechanical processes (spallation and cavity collapse) on UCG cavity evolution is being developed at LLNL with the use of the LDEC (Livermore Distinct Element Code) code. A methodology is also being developed (Morris et al. 2009) to interface the results of the NUFT and LDEC codes to simulate the interaction of mechanical and thermal-hydrological behavior in the host coal/rock, which influences UCG cavity growth. Conditions in the UCG cavity and combustion zone are strongly influenced by water influx, which is controlled by permeability of the host coal/rock and the difference between hydrostatic and cavity pressure. In this paper, we focus on thermal-hydrological processes, examining the relationship between combustion-driven heat generation, convective and conductive heat flow, and water influx, and examine how the thermal and hydrologic properties of the host coal/rock influence those relationships. Specifically, we conducted a parameter sensitivity analysis of the influence of thermal and hydrological properties of the host coal, caprock, and bedrock on cavity temperature and steam production.
Buscheck, T A; Hao, Y; Morris, J P; Burton, E A
Lab Analysis Techniques | Open Energy Information
form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit with form History Facebook icon Twitter icon » Lab Analysis Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Lab Analysis Techniques Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: None Parent Exploration Technique: Exploration Techniques Information Provided by Technique Lithology: Water rock interaction; Rapid and unambiguous identification of unknown minerals; Bulk and trace element analysis of rocks, minerals, and sediments; Obtain detailed information about rock composition and morphology; Determine detailed information about rock composition and morphology; Cuttings are used to define lithology; Core analysis is done to define lithology
Geometry and material choices govern hard-rock drilling performance of PDC drag cutters.
Sandia National Laboratories has partnered with industry on a multifaceted, baseline experimental study that supports the development of improved drag cutters for advanced drill bits. Different nonstandard cutter lots were produced and subjected to laboratory tests that evaluated the influence of selected design and processing parameters on cutter loads, wear, and durability pertinent to the penetration of hard rock with mechanical properties representative of formations encountered in geothermal or deep oil/gas drilling environments. The focus was on cutters incorporating ultrahard PDC (polycrystalline diamond compact) overlays (i.e., diamond tables) on tungsten-carbide substrates. Parameter variations included changes in cutter geometry, material composition, and processing conditions. Geometric variables were the diamond-table thickness, the cutting-edge profile, and the PDC/substrate interface configuration. Material and processing variables for the diamond table were, respectively, the diamond particle size and the sintering pressure applied during cutter fabrication. Complementary drop-impact, granite-log abrasion, linear cutting-force, and rotary-drilling tests examined the response of cutters from each lot. Substantial changes in behavior were observed from lot to lot, allowing the identification of features contributing major (factor of 10+) improvements in cutting performance for hard-rock applications. Recent field demonstrations highlight the advantages of employing enhanced cutter technology during challenging drilling operations.
Wise, Jack LeRoy
Digitally Available Interval-Specific Rock-Sample Data Compiled from Historical Records, Nevada Test Site and Vicinity, Nye County, Nevada
Between 1951 and 1992, underground nuclear weapons testing was conducted at 828 sites on the Nevada Test Site, Nye County, Nevada. Prior to and following these nuclear tests, holes were drilled and mined to collect rock samples. These samples are organized and stored by depth of borehole or drift at the U.S. Geological Survey Core Library and Data Center at Mercury, Nevada, on the Nevada Test Site. From these rock samples, rock properties were analyzed and interpreted and compiled into project files and in published reports that are maintained at the Core Library and at the U.S. Geological Survey office in Henderson, Nevada. These rock-sample data include lithologic descriptions, physical and mechanical properties, and fracture characteristics. Hydraulic properties also were compiled from holes completed in the water table. Rock samples are irreplaceable because pre-test, in-place conditions cannot be recreated and samples cannot be recollected from the many holes destroyed by testing. Documenting these data in a published report will ensure availability for future investigators.
David B. Wood
Roth Rock Wind Power Project | Open Energy Information
Rock Wind Power Project Rock Wind Power Project Jump to: navigation, search Name Roth Rock Wind Power Project Facility Roth Rock Wind Power Project Sector Wind energy Facility Type Commercial Scale Wind Facility Status In Service Owner Gestamp Wind North America Developer Synergics Energy Purchaser Delmarva Power Location South of Red House MD Coordinates 39.30105°, -79.458032° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":39.30105,"lon":-79.458032,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Practices of information and secrecy in a punk rock subculture
By examining the information practices of a punk-rock subculture, we investigate the limits of social media systems, particularly limits exposed by practices of secrecy. Looking at the exchange of information about "underground" shows, we use qualitative ... Keywords: information practices, secrecy, social network sites, subcultures
Jessica Lingel; Aaron Trammell; Joe Sanchez; Mor Naaman
Hot dry rock heat mining: An alternative energy progress report
Mining Heat from the hot dry rock (HDR) resource that lies beneath the earth's crust may provide an almost inexhaustible supply of energy for mankind with minimal environmental effects. In the heat mining process, water is pumped down an injection well into a mass of hydraulically fractured hot rock. As the water flows under high pressure through the opened rock joints, it becomes heated by the rock. It is returned to the surface through a production well (or wells) located some distance from the injector where its thermal energy is recovered by a heat exchanger. The same water is then recirculated through the system to extract more thermal energy. In this closed-loop process, nothing but heat is released to the environment during normal operation. The technical feasibility of HDR heat mining already has been proven by field testing. A long-term flow test is scheduled to begin in 1991 at the world's largest HDR heat mine in New Mexico, USA, to demonstrate that energy can be produced from HDR on a continuous basis over an extended time period. Significant HDR programs are also underway in several other countries. The paper describes the HDR resource, the heat mining concept, environmental characteristics, economics, developments at Los Alamos to date, and HDR development outside the US. 15 refs., 5 figs., 2 tabs.
Duchane, D.V.
New oil source rocks cut in Greek Ionian basin
The Ionian zone of Northwest Greece (Epirus region) constitutes part of the most external zones of the Hellenides (Paxos zone, Ionian zone, Gavrovo Tripolitza zone). The rocks of the Ionian zone range from Triassic evaporites and associated breccias through a varied series of Jurassic through Upper Eocene carbonates and lesser cherts and shales followed by Oligocene flysch. The surface occurrences of petroleum in the Ionian zone are mainly attributed to Toarcian Lower Posidonia beds source rocks and lesser to late Callovian-Tithonian Upper Posidonia beds and to the Albian-Cenomanian Upper Siliceous zone or Vigla shales of the Vigla limestones. Oil that could not be attributed to the above source rocks is believed to have an origin from Triassic formations that contain potential source rocks in Albania and Italy. However, several samples of the shales of Triassic breccias from outcrops and drillholes were analyzed in the past, but the analytical results were not so promising since their hydrocarbon potential was low. In this article, the authors will present their analytical results of the Ioannina-1 well, where for the first time they identified some very rich source beds in the Triassic breccias formation of Northwest Greece.
Karakitsios, V. [Univ. of Athens (Greece); Rigakis, N. [Public Petroleum Corp., Athens (Greece)
Columbia River Channel Improvement Project Rock Removal Blasting: Monitoring Plan
This document provides a monitoring plan to evaluate take as outlined in the National Marine Fisheries Service 2002 Biological Opinion for underwater blasting to remove rock from the navigation channel for the Columbia River Channel Improvement Project. The plan was prepared by the Pacific Northwest National Laboratory (PNNL) for the U.S. Army Corps of Engineers (USACE), Portland District.
Carlson, Thomas J.; Johnson, Gary E.
Micro-crack Damage Evolution of Fracturing Rock Chaotic Characteristics
Chaotic theory and bifurcation of modern nonlinear science were used to study the evolution of micro-cracks under the hydraulic fracturing of the rock mass characteristics, the tensor damage variable which described the chao evolution of micro-cracks ... Keywords: chaos theory, bifurcation theory, damage evolution
Zhaowan Chun; Wang Tingting
Research paper Rock magnetic stratigraphy of a mafic layered sill
Research paper Rock magnetic stratigraphy of a mafic layered sill: A key to the Karoo volcanics intrusion and part of the Karoo Large Igneous Province in South Africa. This well-exposed intrusion consists reserved. Keywords: AMS; magnetic susceptibility; Karoo; Insizwa; gabbro 1. Introduction Studies of Large
Ferré, Eric
Rock mass response to the decline in underground coal mining
Geomechanical problems of mining in the Ostrava-Karvina Coal Basin were studied on the basis of longterm experience gained from seismological observations. They could serve as reasonable models of rock-mass response to temporary reduction and gradual decline in mining activities and mine closure.
Holub, K. [Academy of Science in Czech Republic, Prague (Czech Republic)
1 INTRODUCTION Stressing brittle rocks leads to the development of
-dependent creep driven by stress corrosion and subcritical crack growth (Lockner, 1998). This creep strongly1 INTRODUCTION Stressing brittle rocks leads to the development of distributed damage long before, 1994, Lyakhovsky et al. 1997; Lockner, 1998). Further, the stress-induced damage may facilitate time
Ze'ev, Reches
New project for Hot Wet Rock geothermal reservoir design concept
This paper presents the outlines of a new Hot Wet Rock (HWR) geothermal project. The goal of the project is to develop a design methodology for combined artificial and natural crack geothermal reservoir systems with the objective of enhancing the thermal output of existing geothermal power plants. The proposed concept of HWR and the research tasks of the project are described.
Takahashi, Hideaki; Hashida, Toshiyuki
GEOS898 History on the Rocks Assignment 2
Goggles and aprons Magnifier Graph paper Ruler Colored pencils Small white marker boards (2x3 ft) (Prepare the remaining pictures and rock samples and continue drawing the column using graph paper, rules and colored pencils. (Additional pictures may be used from textbook and internet sources for added clarity.) (20
Frank, Tracy D.
Issues facing the developmt of hot dry rock geothermal resources
Technical and economic issues related to the commercial feasibility of hot dry rock geothermal energy for producing electricity and heat will be discussed. Topics covered will include resource characteristics, reservoir thermal capacity and lifetime, drilling and surface plant costs, financial risk and anticipated rate of return.
Tester, J.W.
Compliant mechanisms
The motivation for this work has been a variety of motions like navigation of pipelines, insertion operations in assembly, and gripping actions, which require the adaptation of the mechanism to the external constraints, rather than avoid them. To this effect, efforts have been made in building mechanisms that obtain the required degrees of freedom through deformations rather than explicit joints in them. Although the use of many joints provides the required number of degrees of freedom, it does so at the cost of making the system very bulky and complex. With the advent of new polymers, the possibility of building joint-free mechanisms that fulfil the requirements of adaptation has increased. Based on this approach, a Magneto Active Polymer (MAP) material has been developed here at the Texas A\\&M University, in which the actuation is performed by the conversion of electromagnetic energy into mechanical energy. The initial experimentation has proved the vast potential of the use of such a material and a few mechanisms like a magneto active peristaltic pump, have been designed and tested for the first time using this material. In this mechanism, the pumping action is obtained when a moving magnetic field produces peristaltic waves in the magneto active material shaped as a tube. Also for the first time, experiments have been conducted to analyze the response of the MAP material to a pulsating magnetic field with the intent of using the experimental results to develop a model of the MAP. In developing the design for the peristaltic pump and other conceptual models described in this thesis, ideas have been drawn from the different modes of locomotion and actuators present in lower organisms. These have been good sources of inspiration for the work done in this thesis and they have been documented in detail.
Venkataraghavan, Janarthanan T
Fluid Migration During Ice/Rock Planetesimal Differentiation
Much speculation on extraterrestrial life has focused on finding environments where water is present. Heating of smaller icy bodies may create and sustain a possible liquid layer below the surface. If liquid water was sustained for geologically significant times (> 108 years) within the ubiquitous small bodies in the outer solar system, the opportunities for development of simple life are much greater. The lifetime of the liquid water layer will depend on several factors, including the rate of rock/water reaction, which will depend on the rate at which water can be segregated from a melting ice/rock core. For the liquid water phase to migrate toward the surface, the denser rock phase must compact. The primary question that this thesis will answer is how fast melt water can segregate from the core of an ice-rich planetesimal. To answer this question we treat the core as two phase flow problem: a compacting viscous �solid� (ice/rock mixture) and a segregating liquid (melt water). The model developed here is based on the approach derived to study a different partially molten solid: in the viscously deforming partially molten upper mantle. We model a planetesimal core that initially a uniform equal mixture of solid ice and rock. We assume chondritic levels of radiogenic heating as the only heat source, and numerically solve for the evolution of solid and melt velocities and the distribution of melt fraction (�porosity�) during the first few million years after accretion. From a suite of numerical models, we have determined that the meltwater is segregated out of the core as fast as it is created, except in the case of very fast melting times (0.75 My vs. 0.62 My), and small ore radius (~25 to 150 km, depending on the viscosity of the ice/rock mixture in the solid core). In these latter cases, segregation is slower than migration and a high water fraction develops in the core. Heat released by water-rock reactions (not included in this model) will tend to drive up melting rates in all cases, which may favor this latter endmember.
Raney, Robert 1987-
Rock Physics Based Determination of Reservoir Microstructure for Reservoir Characterization
One of the most important, but often ignored, factors affecting the transport and the seismic properties of hydrocarbon reservoir is pore shape. Transport properties depend on the dimensions, geometry, and distribution of pores and cracks. Knowledge of pore shape distribution is needed to explain the often-encountered complex interrelationship between seismic parameters (e.g. seismic velocity) and the independent physical properties (e.g. porosity) of hydrocarbon reservoirs. However, our knowledge of reservoir pore shape distribution is very limited. This dissertation employs a pore structure parameter via a rock physics model to characterize mean reservoir pore shape. The parameter was used to develop a new physical concept of critical clay content in the context of pore compressibility as a function of pore aspect ratio for a better understanding of seismic velocity as a function of porosity. This study makes use of well log dataset from offshore Norway and from North Viking Graben in the North Sea. In the studied North Sea reservoir, porosity and measured horizontal permeability was found to increase with increasing pore aspect ratio (PAR). PAR is relatively constant at 0.23 for volumes of clay (V_cl) less than 32% with a significant decrease to 0.04 for V_cl above 32%. The point of inflexion at 32% in the PAR �V_cl plane is defined as the critical clay volume. Much of the scatters in the compressional velocity-porosity cross-plots are observed where V_cl is above this critical value. For clay content higher than the critical value, Hertz-Mindlin (HM) contact theory over-predicts compressional velocity (V_p) by about 69%. This was reduced to 4% when PAR distribution was accounted for in the original HM formulation. The pore structure parameter was also used to study a fractured carbonate reservoir in the Sichuan basin, China. Using the parameter, the reservoir interval can be distinguished from those with no fracture. The former has a pore structure parameter value that is ? 3.8 whereas it was < 3.8 for the latter. This finding was consistent with the result of fracture analysis, which was based on FMI image. The results from this dissertation will find application in reservoir characterization as the industry target more complex, deeper, and unconventional reservoirs.
Adesokan, Hamid 1976-
Acceleration Mechanisms
Glossary I. Background and context of the subject II. Stochastic acceleration III. Resonant scattering IV. Diffusive shock acceleration V. DSA at multiple shocks VI. Applications of DSA VII. Acceleration by parallel electric fields VIII. Other acceleration mechanisms IX. Future directions X. Appendix: Quasilinear equations XI. Bibliography
Melrose, D B
Optimization of Operating Parameters for Minimum Mechanical Specific Energy in Drilling
Efficiency in drilling is measured by Mechanical Specific Energy (MSE). MSE is the measure of the amount of energy input required to remove a unit volume of rock, expressed in units of energy input divided by volume removed. It can be expressed mathematically in terms of controllable parameters; Weight on Bit, Torque, Rate of Penetration, and RPM. It is well documented that minimizing MSE by optimizing controllable factors results in maximum Rate of Penetration. Current methods for computing MSE make it possible to minimize MSE in the field only through a trial-and-error process. This work makes it possible to compute the optimum drilling parameters that result in minimum MSE. The parameters that have been traditionally used to compute MSE are interdependent. Mathematical relationships between the parameters were established, and the conventional MSE equation was rewritten in terms of a single parameter, Weight on Bit, establishing a form that can be minimized mathematically. Once the optimum Weight on Bit was determined, the interdependent relationship that Weight on Bit has with Torque and Penetration per Revolution was used to determine optimum values for those parameters for a given drilling situation. The improved method was validated through laboratory experimentation and analysis of published data. Two rock types were subjected to four treatments each, and drilled in a controlled laboratory environment. The method was applied in each case, and the optimum parameters for minimum MSE were computed. The method demonstrated an accurate means to determine optimum drilling parameters of Weight on Bit, Torque, and Penetration per Revolution. A unique application of micro-cracking is also presented, which demonstrates that rock failure ahead of the bit is related to axial force more than to rotation speed.
Hamrick, Todd
First measurement of low intensity fast neutron background from rock at the Boulby Underground Laboratory
A technique to measure low intensity fast neutron flux has been developed. The design, calibrations, procedure for data analysis and interpretation of the results are discussed in detail. The technique has been applied to measure the neutron background from rock at the Boulby Underground Laboratory, a site used for dark matter and other experiments, requiring shielding from cosmic ray muons. The experiment was performed using a liquid scintillation detector. A 6.1 litre volume stainless steel cell was filled with an in-house made liquid scintillator loaded with Gd to enhance neutron capture. A two-pulse signature (proton recoils followed by gammas from neutron capture) was used to identify the neutron events from much larger gamma background from PMTs. Suppression of gammas from the rock was achieved by surrounding the detector with high-purity lead and copper. Calibrations of the detector were performed with various gamma and neutron sources. Special care was taken to eliminate PMT afterpulses and correlated background events from the delayed coincidences of two pulses in the Bi-Po decay chain. A four month run revealed a neutron-induced event rate of 1.84 +- 0.65 (stat.) events/day. Monte Carlo simulations based on the GEANT4 toolkit were carried out to estimate the efficiency of the detector and the energy spectra of the expected proton recoils. From comparison of the measured rate with Monte Carlo simulations the flux of fast neutrons from rock was estimated as (1.72 +- 0.61 (stat.) +- 0.38 (syst.))*10^(-6) cm^(-2) s^(-1) above 0.5 MeV.
E. Tziaferi; M. J. Carson; V. A. Kudryavtsev; R. Lerner; P. K. Lightfoot; S. M. Paling; M. Robinson; N. J. C. Spooner
Office of Legacy Management (LM)
MISCELLANEOUS PAPER S71-17 MISCELLANEOUS PAPER S71-17 EARTHQUAKE RESISTANCE OF EARTH AND ROCK-FILL DAMS Report 2 ANALYSIS OF RESPONSE O F RIFLE.GAP D A M TO PROJECT RULISON UNDERGROUND NUCLEAR DETONATION bv J. E. Ahlberg, J. Fowler, L W. Heller ........ . . . . . . . . - . . . . . . . . . . . . . . . - . . - ...... *- , .... . . . - ->-w-J- * - : - . . June 1972 s~omsored by Office, Chief of Engineers, U. S. Army Conducted by U. S. A m y Engineer Waterways Experiment Station Soils and Pavements Laboratory Vicksburg, Mississippi APPROVED FOR WBLlC RELEASE: DISTRIBUTION UNLIMITED L i s t o f Associated Reports Previous reports under Engineering Study 540 are: "A Comparative Summary o f Current Earth Dam Analysis Methods for Earthquake Response," issued by Office, Chief o f Engineers, a s Inclosure 1 to Engineer
Drip shield Structural Response to Rock Fall
The objective of this calculation is to determine areas over the drip shield (DS) top plate and side-walls where the residual stress values exceed 50% of Ti-7 yield strength. These areas will also be referred to as the damaged areas throughout this document. The scope of this document is limited to reporting the calculation results in terms of the damaged areas based on a chosen set of stress components. This calculation is intended for use in support of the preliminary design activities for the license application design of the DS. This calculation is associated with the DS design and was performed by the Waste Package and Components. AP-3.12Q, ''Design Calculations and Analyses'' is used to perform the calculation and develop the document. The DS is classified as a safety category item. Therefore, this calculation is subject to the Quality Assurance Requirements and Description. The information provided by the sketches attached to this calculation is that of the potential design of the type of DS considered in this calculation and provides the potential dimensions and materials for the DS design. The finite element (FE) calculation was performed by using the commercially available LS-DYNA Version (V)960 (Software Tracking Number [STN] 10300-960.1106-00, Ref. 7) FE code. The results of this calculation were evaluated using residual first principal stress. Subsequent analysis of areas determined by residual stresses have been reported in the results section of this document. The finite element mesh adequacy was determined based on the maximum stress intensity and maximum first principal stress. The current work processes and procedures for the control of the electronic management of data for this activity were conducted in accordance with AP-3.13Q, ''Design Control'' (Section 5.1.2).
Z. Ceylan
A Hydro-Thermo-Mechanical Numerical Model For Hdr Geothermal Reservoir
Hydro-Thermo-Mechanical Numerical Model For Hdr Geothermal Reservoir Hydro-Thermo-Mechanical Numerical Model For Hdr Geothermal Reservoir Evaluation Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Hydro-Thermo-Mechanical Numerical Model For Hdr Geothermal Reservoir Evaluation Details Activities (0) Areas (0) Regions (0) Abstract: A two-dimensional numerical model of coupled fluid flow, heat transfer and rock mechanics in naturally fractured rock is developed. The model is applicable to assessments of hot dry rock (HDR) geothermal reservoir characterisation experiments, and to the study of hydraulic stimulations and the heat extraction potential of HDR reservoirs. Modelling assumptions are based on the characteristics of the experimental HDR reservoir in the Carnmenellis granite in Cornwall, S. W. England. In
Proceedings of the second international symposium on rock fragmentation by blasting
This is the second international meeting of researchers in rock fragmentation by blasting. The symposium continues the information exchange initiated at the previous conference and to determine relevant directions for future research on fracture and fragmentation of rock.
Fourney, W.L.; Dick, R.D. (Maryland Univ., College Park, MD (USA))
Spectral properties and reflectance curves of the revealed volcanic rocks in Syria using radiometric measurements
This research aimed at studying the spectral reflectance intensity of different exposed volcanic rocks in Syria, and drawing their curves by radiometer measurements. In order to reach this goal, we have studied different kinds of volcanic rocks related ...
M. Rukieh; A. M. Al-Kafri; A. W. Khalaf
Transport and seismoelectric properties of porous permeable rock : numerical modeling and laboratory measurements
The objective of this thesis is to better understand the transport and seismoelectric (SE) properties of porous permeable rock. Accurate information of rock transport properties, together with pore geometry, can aid us to ...
Zhan, Xin, Ph. D. Massachusetts Institute of Technology
Search for underground openings for in situ test facilities in crystalline rock
With a few exceptions, crystalline rocks in this study were limited to plutonic rocks and medium to high-grade metamorphic rocks. Nearly 1700 underground mines, possibly occurring in crystalline rock, were initially identified. Application of criteria resulted in the identification of 60 potential sites. Within this number, 26 mines and 4 civil works were identified as having potential in that they fulfilled the criteria. Thirty other mines may have similar potential. Most of the mines identified are near the contact between a pluton and older sedimentary, volcanic and metamorphic rocks. However, some mines and the civil works are well within plutonic or metamorphic rock masses. Civil works, notably underground galleries associated with pumped storage hydroelectric facilities, are generally located in tectonically stable regions, in relatively homogeneous crystalline rock bodies. A program is recommended which would identify one or more sites where a concordance exists between geologic setting, company amenability, accessibility and facilities to conduct in situ tests in crystalline rock.
Wollenberg, H.A.; Strisower, B.; Corrigan, D.J.; Graf, A.N.; O'Brien, M.T.; Pratt, H.; Board, M.; Hustrulid, W.
Modeling of thermally driven hydrological processes in partially saturated fractured rock
the heat source and encounters cooler rock, it condenses,fractured rock near the radioactive-decay heat source isrock, giving rise to a reflux of liquid back to the heat source.
Tsang, Yvonne
Mechanism and environmental effects on MEOR induced by the alpha process
This project was an interdisciplinary investigation of the enhanced oil recovery effects of a commercial microbial enhanced oil recovery (MEOR) system. The purpose was to investigate in parallel laboratory and field studies the response of a portion of the Shannon Sandstone reservoir to two single-well treatments with a commercial MEOR system, to investigate basic bacteria/rock interactions, and to investigate mechanisms of oil release. The MEOR system consisted of a mixed culture of hydrocarbon-utilizing bacteria, inorganic nutrients, and other growth factors. Parallel field and laboratory investigations into the effect and mechanisms of the treatment were carried out by independent principal investigators. The Shannon Sandstone at the Naval Petroleum Reserve [number sign]3 (NPR [number sign]3), Teapot Dome Field, Wyoming, was the location of the pilot field treatment. The treated and adjacent observation wells showed production and microbiological perturbations that are attributed to the effects of treatment during the first four post-treatment months. Effects of treatment declined to background levels within four months of inoculation. No production response was recorded in control wells unaffected by microbial stimulation. Laboratory research resulted in descriptions of colonization patterns of hydrocarbon-utilizing bacteria in the reservoir rock environment. Core-flooding research utilizing various components of the MEOR system did not result in the isolation of an oilrelease mechanism or measure incremental oil recovery from cores at residual oil saturation to waterflood. Chemical analysis of pre- and post-treatment produced oil identified large organic acid molecules concentrated in the asphaltenic fraction of posttreatment oil, but not in the oil from untreated control wells. No significant changes were measured in the overall quality of the oil produced from MEOR treated wells.
Hiebert, F.K.; Zumberge, J.; Rouse, B.; Cowes, A.; Lake, L.W.
Mechanism and environmental effects on MEOR induced by the alpha process. Final report
This project was an interdisciplinary investigation of the enhanced oil recovery effects of a commercial microbial enhanced oil recovery (MEOR) system. The purpose was to investigate in parallel laboratory and field studies the response of a portion of the Shannon Sandstone reservoir to two single-well treatments with a commercial MEOR system, to investigate basic bacteria/rock interactions, and to investigate mechanisms of oil release. The MEOR system consisted of a mixed culture of hydrocarbon-utilizing bacteria, inorganic nutrients, and other growth factors. Parallel field and laboratory investigations into the effect and mechanisms of the treatment were carried out by independent principal investigators. The Shannon Sandstone at the Naval Petroleum Reserve {number_sign}3 (NPR {number_sign}3), Teapot Dome Field, Wyoming, was the location of the pilot field treatment. The treated and adjacent observation wells showed production and microbiological perturbations that are attributed to the effects of treatment during the first four post-treatment months. Effects of treatment declined to background levels within four months of inoculation. No production response was recorded in control wells unaffected by microbial stimulation. Laboratory research resulted in descriptions of colonization patterns of hydrocarbon-utilizing bacteria in the reservoir rock environment. Core-flooding research utilizing various components of the MEOR system did not result in the isolation of an oilrelease mechanism or measure incremental oil recovery from cores at residual oil saturation to waterflood. Chemical analysis of pre- and post-treatment produced oil identified large organic acid molecules concentrated in the asphaltenic fraction of posttreatment oil, but not in the oil from untreated control wells. No significant changes were measured in the overall quality of the oil produced from MEOR treated wells.
Estimation of host rock thermal conductivities using the temperature data from the drift-scale test at Yucca Mountain, Nevada
host rock in the immediate vicinity of the heat source. Insource of heating and condensed in the cooler parts of the rock.sources, heat transfer was still happening on account of the wet rock.
Mukhopadhyay, Sumitra; Tsang, Y.W.
Analysis Analysis of Short-Bunch Production with the APS Booster and a Bunch Compressor Michael Borland, AOD/OAG ∗ August 8, 2003 1 Abstract There is significant interest among x-ray scientists in short-pulse x-rays. The x-rays from the APS ring, although very bright, are produced by an electron bunch with an rms length of more than 30 ps. Typically, it is only a linear accelerator that can produce a very short bunch. An idea was brought to my attention by Glenn Decker that might allow us to produce a short bunch using the APS booster. This idea involves extracting the beam from the booster at 3 to 4 GeV, while it is still relatively short, then compressing it with a magnetic bunch compressor. In this note, we present a preliminary analysis of this idea, along with the related idea of using a nonequilibrium beam from the APS photoinjector. 2 Background We will begin with an examination of the ideal result
Direct mechanical energy measures of hammer mill comminution of switchgrass, wheat straw, and corn stover and analysis of their particle size distributions
Biomass particle size impacts handling, storage, conversion, and dust control systems. Size reduction mechanical energy was directly measured for switchgrass (Panicum virgatum L.), wheat straw (Triticum aestivum L.), and corn stover (Zea mays L.) in an instrumented hammer mill. Direct energy inputs were determined for hammer mill operating speeds from 2000 to 3600 rpm for 3.2 mm integral classifying screen and mass input rate of 2.5 kg/min with 90 - and 30 -hammers. Overall accuracy of specific energy measurement was calculated as 0.072 MJ/Mg. Particle size distributions created by hammer mill were determined for mill operating factors using ISO sieve sizes from 4.75 to 0.02 mm in conjunction with Ro-Tap sieve analyzer. A wide range of analytical descriptors were examined to mathematically represent the range of particle sizes in the distributions. Total specific energy (MJ/Mg) was defined as size reduction energy to operate the hammer mill plus that imparted to biomass. Effective specific energy was defined as energy imparted to biomass. Total specific energy for switchgrass, wheat straw, and corn stover grinding increased by 37, 30, and 45% from 114.4, 125.1, and 103.7 MJ/Mg, respectively, with an increase in hammer mill speed from 2000 to 3600 rpm for 90 -hammers. Corresponding total specific energy per unit size reduction was 14.9, 19.7, and 13.5 MJ/Mg mm, respectively. Effective specific energy of 90 -hammers decreased marginally for switchgrass and considerably for wheat straw and it increased for corn stover with an increase in speed from 2000 to 3600 rpm. However, effective specific energy increased with speed to a certain extent and then decreased for 30 -hammers. Rosin Rammler eq