Below Cave Point11 bedrock mortars all one one rock.Think those big holes are geoconcretions? Think again. They are huge bowl mortars. Their side walls bulge out into the surrounding rock in a classic “Olla” shape–the bowl is wider at the side walls than it is at the rim. The bottoms of these bowls are basically […]
Macedo Ranch4 bedrocks in the saddle of the “China Wall”.1 bedrock mortar and a grinding slick on ridge top above.This site is very near the Volvon/Tatcan tribelet boundary.Bob and Jim approach the China Wall.There are some surprisingly deep bedrock mortars here.A closeup of the deepest mortar. We call mortars with interiors like this “bullet-shaped.”
North Walpert LookoutTwo bedrock mortars.Elevation 1480 ft.Jeff certainly has a flair for discovering obscure, out-of-the-way sites.The views form this site are phenomenal.Looking west over Stonebrae.Mt. Diablo and the Black Hills rise in the distance.Oh yeah…one of the mortars.Photographs by Bob Bardell.
Sulphur Spring18 cupule rock; 5 bedrock mortars; slick 70′ away.Elevation 722 ft.The cupule rock. The use of cupule rocks here and elsewhere is, for the most part, shrouded in mystery. See Cupule Petroglyphs in the Diablo Range by E. Breck Parkman in the Journal of California and Great Basin Anthropology Vol. 8, No. 2, pp. […]
Frick Lake16 bedrock mortars and anvils.This site hugs the southwestern boundary of Brushy Peak Regional Preserve. Thanks to Joel for discovering it.Looking down at the site and at Frick Lake.Photograph by Bob Bardell.The mortar rocks.A closeup of one of the mortar rocks.Another mortar rock. Note the range of mortar sizes–from the cupule/anvil through the shallow […]
Lake Del Valle, Campsite 7414 cupule rock and 1 small bedrock mortar on rock in the nearby creekElevation 714 ft.Thanks to Joel and Alex for discovering these rocks.The cupule rock was likely moved here. The patterns of cupules appear non-random, which suggests they may have had representational functions.This shallow mortar is difficult to make out […]