Basic geologic mapping is the foundation for any comprehensive study undertaken to evaluate earth science related societal and environmental issues. The Regional Geologic Mapping Project (RGMP) was established to prepare and maintain a baseline source of the most current information on the framework geology of California. RGMP geologists map and compile geologic maps of the state and its offshore continental margin at various scales. The RGMP works in cooperation with the U.S. Geological Survey (USGS) through STATEMAP and SCAMP. Geologic mapping priorities are established under the direction of the State Geologist and the California Geologic Mapping Advisory Committee.

Products include statewide 1:750,000-scale fault activity and geologic maps; 1:250,000-scale geologic atlas and regional geologic map series and offshore continental margin maps; 1:100,000 and 1:24,000-scale quadrangle maps of selected areas of the state. Other products include indexes to geologic mapping and graduate theses.

Preliminary Geologic Maps are intended to provide the public timely access to digital 1:24,000 and 1:100,000 scale geologic maps being prepared by the Regional Geologic Mapping Program. Technical comment is welcome. Geologic mapping priorities are established by the State Geologist and the California Geologic Mapping Advisory Committee.

STATEMAP is a cooperative geologic mapping program funded by the USGS through the National Mapping Act. Funding is provided for successful proposals to participating states for the explicit purpose of developing digital geologic maps for areas shown to have significant societal needs. States awarded funding are required to provide matching funds. Click here to view the California STATEMAP Project Information Sheet.