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Map showing sampled radiolarian localities in the western Paleozoic and Triassic belt, Klamath Mountains, California

The western Paleozoic and Triassic belt, the largest of several major subdivisions of the Klamath Mountains geologic province, extends 300 km northward from the south end of the province in California to the north end of the province in Oregon (see inset map). The rocks of the belt are mainly sedimentary and volcanic, including tuff, cherty tuff, chert, argillite, limestone, and volcanic flows and

Geologic map showing springs rich in carbon dioxide or or chloride in California

Carbon dioxide- and chloride-rich springs occur in all geologic provinces in California, but are most abundant in the Coast Ranges and the Great Valley. The carbon-dioxide-rich springs issue mainly from Franciscan terrane; they also are rich in boron and are of the metamorphic type (White, 1957). Based on isotopic data, either the carbon dioxide or the water, or both, may be of metamorphic origin.

Landslide susceptibility in San Mateo County, California

Information on areas susceptible to failure by landsliding is available in many general geologic maps and reports.  However, it is commonly presented in complex, technical language, together with data not connected with slope stability.  This derivative map is intended to convey such information in nontechnical form so that it will be intelligible to the non-geologist.  It portrays only those geol