the marine terrace, indicating their ancient genesis on the sea floor prior to uplift. These rock formations are characteristically composed of sandstone with layers of quartz. The active San Andreas Fault runs roughly parallel and near to the coastline of Goat Rock Beach. Soils within the site are classified as coastal beach sands (where rocky shoreline is not evident) and escarpment group soils on the marine terrace; typically soils above the marine terrace are in the Rohnerville loam group. Most of the beach sands consist of a medium coarse brown to gray sandy materials, reflecting the high rate of erosion of escarpment soils into the ocean; however, there are patches of dark gray smooth pebble beach such as the approximately stretch lying immediately north of Goat Rock. The beach is changed every year. Area history The oldest natural history of this area related to mammals manifests in a series of rock outcrops about one third of a mile south of Goat Rock Beach, positioned above the shoreline on a low lying marine terrace. There are uplifted sea stack formations with prominent rubbing marks about in elevation above the ground surface, a height too high to have been caused by modern bovids. Mammoths are believed to have roamed here as recently as 40,000 years ago, and they are thought to have created these severe rubbing marks. Mammoth fossil remains have been found at Bodega Head at the south end of Sonoma Coast State Beach. The earliest known human settlement of this site was by the Native American Coast Miwok and Pomo tribes. As early as 1849 archaeological discoveries were recorded in the vicinity, and to date several prehistoric kitchen middens and other types of tribal habitation finds have been made. Goat Rock Beach is part of the Mexican land grant rancho Bodega. The Russians are thought to have begun logging the old-growth forests directly above the coastal prairie in the early 19th century. The underwater delineation of the property is considered to extend to from the shoreline. While no shipwrecks have been discovered, the literature indicates that there are at least 17 vessels which may have been lost in these waters. There are remains of numerous historic barns and other agricultural buildings on the coastal prairie several miles south of Goat Rock Beach, indicating 19th century settlement by Europeans; to the south, at Duncans Landing there are iron pins embedded in