The California Geological Survey, previously known as the California Division of Mines and Geology, is the California state geologic agency.
Although it was not until 1880 that the California State Mining Bureau, predecessor to the California Geological Survey, was established, the "roots" of California's state geological survey date to an earlier time. As might be expected for a state that owed its existence to the gold rush of 1849, the California State Legislature recognized that geologists could provide valuable information. In 1851, one year after California was admitted to the United States, the Legislature named John B. Trask, a medical practitioner and active member of the California Academy of Sciences, as Honorary State Geologist. In 1853 the Legislature passed a joint resolution asking him for geological information about the state. He submitted a report On the Geology of the Sierra Nevada, or California Range. About two months later, the Legislature created the first California Geological Survey headed by Trask, who retained the title of State Geologist.
Within a few years the mining of placer gold began to decline and mining of quartz lodes began. These changes, coupled with publication of reports by Trask, created a public clamor for a state geological survey. In 1860 the Legislature passed an act creating the Office of State Geologist and defining the duties thereof. The act named Josiah D. Whitney (for whom Mount Whitney is named) to fill the office. A Yale graduate, Whitney had worked on several surveys in the east. The act directed Whitney to make an accurate and complete geological survey of the state.
Whitney chose William Henry Brewer as chief botanist to lead the original field party. Brewer then added Clarence King, James Gardiner, topographer Charles F. Hoffmann and packer Dick Cotter. It was one of the most ambitious geological surveys ever attempted and yielded a vast amount of information about California that was hitherto unknown and unpublished. Among the natural features of California they were the first to describe Kings Canyon, which they discovered in 1864. The original California Geological Survey influenced the future of surveying and spurred the creation of the United States Geological Survey. Funding for the field work was limited and the last field work was done in 1870 by Hoffmann and W. A. Goodyear. In 1874 the Survey was officially ended due to hostility between then Governor of California Newton Booth and Whitney.