Please Note: This is an archived website. It is recommended to search on-line for revised or newer information.
USGS Banner with Mount Shasta
Western Earth Surface Processes Team

Geologic Mapping in Northern California

This website provides access to selected geologic mapping in Northern California. Mapping products presented here include digital geologic databases of 1:100,000-scale maps that can be powerfully adapted to multiple tasks. They can be used to conduct geologic inquiries, to help evaluate of geologic hazards, and help agencies manage their natural resources. The digital map databases were produced by the USGS Western Earth Surface Processes team.


Index map of CA
Click on the mapto see mapping project areas and link to descriptions of the maps.

Geologic mapping in the region is ongoing. However, much of the field mapping presented here was conducted in the 1980's and 1990's as part of an effort to provide a digital geologic database across Northern California at a scale of 1:100,000. Field mapping was compiled into digital database format. This comprehensive geologic dataset will provide geologists in federal, state, and local agencies the ability to evaluate and interpret the physical characteristics of forest and rangeland ecosystems to make sound land management decisions, such as timber harvest practices, watershed restoration opportunities, and minerals/materials inventories. The database will also be useful in preparing geomorphic analyses of drainage basins, interpretive displays and brochures for the public, and a number of other purposes on both public and private lands.


Information on geologic maps 

San Francisco Bay Regional Mapping


Northern California Transect Mapping

Other regional maps

Please note! There are many publications and maps produced about Northern California by the USGS and other organizations including the California Geological Survey. The USGS National Geologic Map Database provides access to geologic maps on many scales. A search on the Internet may lead you to many resources not shown here. Many libraries have older, printed publications that are not yet available online.

For educational resources see the USGS Educational Resources website.

For USGS technical reports, search the USGS Publications Warehouse.


Return to the Main Page
FirstGov button 

Cape Mendicino Quadrangle Hayfork Quadrangle Garberville Quadrangle Covelo Quadrangle Red Bluff Quadrangle Willows Quadrangle Lake AlmonorQuadrangle Susanville Quadrangle San Francisco Bay Region Southern California Geologic Maps Eureka Quadrangle Monterey Beatty