This polygon shapefile represents earthquake zones in San Joaquin County, California as of July 2015. Zones were established by the California Geological Society (CGS). This layer is part of a collection of GIS data for San Joaquin County in California.This dataset is intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production, or to provide a basemap to support graphical overlays and analysis with other spatial data.