Mulholland Formation
The Mulholland Formation is a Pliocene epoch geologic formation in the Berkeley Hills and San Leandro Hills of the East Bay region of the San Francisco Bay Area, California. It is found within Alameda County and Contra Costa County.
Geology
It overlies the Bald Peak Basalt formation, and underlies the Pleistocene epoch Leona Rhyolite formation. It is composed of siltstone, sandstone, and conglomerates. It has fluviatile and lacustrine deposits.Descending under the Bald Peak Basalt formation are the Pliocene epoch units of the Siesta Formation, Moraga Formation, and Orinda Formation. Below the Orinda are the local Miocene epoch units of the Monterey Formation Group: Tice Shale, Oursan Sandstone, Claremont Shale, and Sobrante Sandstone.
Fossils
The Mulholland Formation preserves fossils dating back to the Neogene period.Other local formations
- Units of other local formations in the Berkeley and San Leandro Hills, in descending geologic column order from higher/younger to lower/older, include: