Digital geologic map and map database of parts of Marin, San Francisco, Alameda, Contra Costa, and Sonoma Counties, California

This digital map database, compiled from previously published and
unpublished data, and new mapping by the authors, represents the
general distribution of bedrock and surficial deposits in the mapped area.
Together with the accompanying text file (mageo.txt, mageo.pdf, or
mageo.ps), it provides current information on the geologic structure and
stratigraphy of the area covered. The database delineates map units that
are identified by general age and lithology following the stratigraphic
nomenclature of the U.S. Geological Survey. The scale of the source maps
limits the spatial resolution (scale) of the database to 1:62,500 or
smaller.