This polygon shapefile depicts the general distribution and identity of geologic materials in the nine county San Francisco Bay Area Region, Californiabased on United States Geological Survey data. Although based on the units distinguished on geologic maps, it is not itself a geologic map because it does not address geologic structure or the stratigraphic organization of the map units in a systematic way. Instead, it is directed at the distribution and physical character of the geologic materials, following the pattern of its progenitors, Wentworth and others (1985) and Ellen and Wentworth (1995). This dataset was developed/compiled for use in the San Francisco Bay Area Upland Habitat Goals Project, a Project used to identify a Conservation Lands Network (CLN) for biodiversity preservation to inform conservation investments and lasting cooperative conservation partnerships. The Conservation Lands Network GIS Database is the primary output of the Project. The data depicts the spatially explicit CLN that is recommended for the nine county San Francisco Bay Area Region, California.