and their dip varies from 14 to 23 degrees. In addition to the gravel dunes and antidunes, delta-like, expansion bars accumulated below each of the former subaqueous inlets. They consist of foreset beds that consist of boulder-cobble-pebble gravels. The Pleistocene deposits and bedforms in the basin have not been dated using radiometric dating methods. The lack of absolute dates prevents the construction of a reliable geochronology for Lake Missoula lake drainage events in the Camas Prairie basin and correlation of the giant current ripples with bedforms and sedimentary deposits outside of it. The exposed gravel deposits underlying the giant current ripples at Camas Prairie exhibit at least two beds of gravelly deposits that are indicative of deposition by separate Missoula floods. They are separated by an erosional unconformity with a buried and dismembered calcrete, carbonate soil horizon. The calcrete is thick. It provides empirical evidence of at least two separate periods of giant current ripple activity and associated with separate Missoula Floods that occurred thousands of years apart based the thickness and development of the calcrete. The giant current ripples of the Camas Prairie are analogous to similar giant Pleistocene bedforms described form Channeled Scablands of Washington. They are identical to the giant subaqueous bedrooms that formed on the bottom of Lake Kuray-Chuya during the Altai flood in Siberia, Russia. These giant bedforms, which are rare or unknown outside of theoretical and experimental studies, preserved a unique record of the paleohydraulology of a Missoula Flood associated with the catastrophic emptying of Lake Missoula. See also Ice Age Floods National Geologic Trail Palouse prairie References External links Visit North Central Idaho – Camas Prairie Eye of Idaho – Around Camas Prairie Idaho Public TV – Camas Prairie Railroad Historical Museum at St. Gertrude Monastery of St. Gertrude Glacial Lake Missoula.org – Camas Prairie ripple marks in Montana Plants by habitat Regions of Idaho Regions of Montana Grasslands of the United States Grasslands of Idaho Grasslands of Montana Geography of Washington (state) Flora of the Northwestern United States Geography of Camas County, Idaho Geography of Idaho County, Idaho Geography of Lewis County, Idaho Nez Perce National Historical Park