Claremont Shale

The Claremont Shale is a Miocene epoch geologic formation in the Berkeley Hills of the East Bay region of the San Francisco Bay Area, California.
It is found within the Claremont Canyon area of the Berkeley Hills in Alameda County and Contra Costa County.
The Claremont Shale formation preserves fossils dating back to the Miocene epoch of the Neogene period.