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 Kern County earthquake and its aftershocks
1952 Kern County earthquake
1952 Kern County earthquake
California Geological Survey