Quaternary Surficial Deposits Southern CA

-->Since November 2007, the Department of Conservation's California Geological Survey (CGS) has been a technical consultant to the Department of Water Resources (DWR) and its Alluvial Fan Task Force (AFTF) for a 10-county southern California area including San Bernardino, Riverside, Los Angeles, Ventura, Santa Barbara, San Luis Obispo, Kern, Orange, Imperial, and San Diego. In this capacity, CGS has assisted in identifying geologic hazards and natural resources that could affect or be affected by development on alluvial fans, and in preparing guidance for alluvial fan floodplain management. The CGS Compilation of Quaternary Surficial Deposits in Southern California was designed as a regional-scale planning tool to assist DWR, the AFTF, and local communities in evaluating future development on alluvial fans. The detailed geologic features shown on recent high-resolution geologic maps that cover portions of southern California from Santa Barbara to San Diego have been compiled into a single source GIS dataset. A derivative GIS dataset has also been created that merges geologic mapping from various authors, and at different scales, into a common seamless format that normalizes and differentiates the various alluvial fan and related Quaternary deposits into forty geological units for the entire area at a scale of 1:100,000.