California Geological Survey - Later Organizations

Later Organizations

In 1880 the State Mining Bureau was established by the Legislature. The establishment of the Bureau was a direct action in response to the need for information on the occurrence, mining, and processing of gold in the state. Its focus was on California's mining industry and the Governor appointed the State Mineralogist. In 1891, the Bureau published the first geologic map of the state showing eight stratigraphic units in color, along with numerous blank areas where information was lacking. The second colored geologic map of the state, published in 1916, showed 21 stratigraphic units and was accompanied by an explanatory volume (Bulletin 72, Geologic Formations of California).

In 1927 the Bureau became the Division of Mines within the Department of Natural Resources. In 1928, with the hiring of the first geologist, the focus of the Division began to shift towards the gathering of basic geologic information. In 1938 a new 1:500,000-scale geologic map was published.

During the 1940s and 1950s, the Division developed as a state geological survey and two well-defined branches were established: the Mining Engineering Branch and the Geology Branch. The Division began processing numerous geological quadrangle maps and reports for publication. In 1952 the Division conducted its first public-safety related effort by documenting the impacts of the 1952 Arvin-Tehachapi earthquakes.

The 1960s were years of development of new programs and modernization of long-standing programs. In 1962, eighty-one years after its creation, the Division of Mines was renamed the Division of Mines and Geology (DMG). Its focus had shifted from an organization that was primarily mine-oriented to one responsible for a broader range of practical applications of geology, especially geologic hazards and seismic hazards. A highlight of the decade was the completion in 1966 of the geologic mapping program.

From the early 1970s to the present, Division programs have expanded often due to the passage of legislation. Following earthquakes and landslide damage during the 1970s and 1980s, legislation passed which clearly focused DMG’s authority on several fronts, including:

• Establishing the Strong-Motion Instrumentation Program to obtain statewide records of the response of rock, soil, and structures to ground motion caused by earthquakes.
• Enacting the Alquist Priolo Special Studies Zone Act, mandating the delineation of zones along traces of hazardous faults.
• Enacting the Surface Mining and Reclamation Act to ensure that significant mineral deposits are identified and protected and the reclamation of mined lands.
• Declaring that the California Department of Conservation is the primary state agency responsible for geologic hazard review and investigation.
• Enacting the Seismic Hazards Mapping Act, establishing a program to identify and map seismic hazard zones.

Language was also added which outlined DMG’s responsibilities as encompassing:

• Hazard assessment - identification and mapping of geologic hazards and estimates of potential consequences and likelihood of occurrence.

• Information and advisory services including maintenance of a geologic library, public education program, maintenance of a geologic data base, review functions, and expert consulting to federal, state and local government agencies.

• Emergency response including monitoring and assessment of anomalous geologic activity, and operation of a clearinghouse for post-event earth science investigations.

• Development and application of mitigation methods, including identifying state research needs, facilitating needed research, and expediting the application of new research results to public policy.