Don Edwards Preserve4 bedrock mortars, possible cupulesElevation 103 ft.Another one of Jeff’s amazing finds.Nearly all the bedrock mortars we’ve encountered in the Bay Area occur on sandstone. These are the only ones we’ve seen in metamorphic chert.A closer look. Note the paired, shallow mortars. Such arrangements are rare. The only others we’ve seen are on […]
Mission San JoseEstablished in 1797 at the Alson village of Oroysom.The mission complex as it appeared prior to its destruction in 1868 by the last great earthquake on the Hayward Fault.Image courtesy of the Bancroft Library.The church and museum at Mission San Jose are open from 10 AM to 5 PM daily except for New […]
Stromer Spring25 bedrock mortars, cupules, and PCN-style petroglyphsElevation 2023 ft.We used to drink from Stromer Spring in the not-so-distant past. The Park District warns against doing it now.A nice, single-track trail passes near here. We followed it many times without ever stopping to examine these rocks. If we considered them at all, we dismissed them […]
Alvarado Park2 bedrock mortars, 275+ cupules, 2 PCNs, and midden behind gazebo.This chlorite blueschist outcropping on Wildcat Creek has more cupules on it than any other we know of in the Bay Area. Was it just the blueschist found here and on Baxter Creek that attracted cuple-makers, or was something else at work?Jim and Heather […]
Guadalupe Oak Grove Park4 bedrock mortarsElevation 296 ft.A funnel-shaped mortar or a small cone with a broad flaring mouth? You make the call.Skeptical Bob runs his hand over the inner surface of this shallow concavity to determine whether if feels “worked.” It does.A shallow mortar.Photograph by Bob Bardell.The mortar on this rock may have started […]
Pinole Shores ShellmoundElevation 16 ft.Dave turned us on to this mound. Keep up the good work Dave!Perhaps this mound is best described as a “shell heap”. It’s spread all over the top of the spit.We’ve identified Ostrea lurida (Olympia oyster), Mytilus californianus (California mussel), and Mytilus edulis (blue mussel) at this site.Photographs by Bob Bardell.
Canyon Middle School8 bedrock mortars on two rocksElevation 302 ft.Thanks to Joel for discovering this charming site.One of the mortar rocks here sits near the edge of a steep cliff above Crow Canyon Road and the buried Crow Creek.There are beautifully proportioned mortars on this rock.Another beautiful mortar rock sits in a little meadow not […]