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California Geological Survey - Alquist-Priolo Fault Zones in Electronic Format 

Alquist-Priolo Earthquake Fault Zones in California – Statewide Collection in Electronic Format

Available on CD-ROM

Earthquake Fault Zone Regions index map

The California Geological Survey is pleased to announce that the statewide collection of Alquist-Priolo Earthquake Fault Zone (APEFZ) maps is now available in electronic format. Statewide coverage is divided into three geographic regions and includes the Southern Region, Central Coastal Region, and Northern and Eastern Region.

Northern and Eastern Region contains coverage of Alpine, Butte, Humboldt, Inyo, Lassen, Mendocino, Modoc, Mono, Shasta, and Siskiyou counties.

Central Coastal Region contains coverage of Alameda, Contra Costa, Fresno, Kern, Lake, Marin, Merced, Monterey, Napa, San Benito, San Francisco, San Luis Obispo, San Mateo, Santa Clara, Santa Cruz, Solano, Sonoma, Stanislaus, and Yolo counties.

Southern Region contains coverage of Imperial, Los Angeles, Orange, Riverside, San Bernardino, San Diego, Santa Barbara, and Ventura counties

For each region, two distinctly different types of electronic coverage are available:

Digital images (digital raster graphic files) of the maps - Digital Images of Official Maps of Alquist-Priolo Earthquake Fault Zones of California (CD 2000-03 – Southern Region, CD 2000-04 – Central Coastal Region, CD 2000-05 - Northern and Eastern Region).
Digital raster graphic coverage is in pdf format and can be viewed using the included Adobe Acrobat Reader software program. The images essentially are a picture of the official map, which includes the APEFZ regulatory zones and faults placed over a U.S. Geological Survey base map (scanned from original 1:24,000 scale maps). The CD's are sold separately and, in addition to pdf images of Earthquake Fault Zone maps, include a digital version of Special Report 42, Fault-Rupture Hazard Zones in California, which explains the Alquist-Priolo Earthquake Fault Zoning (AP) Act, the zoning program, and associated regulations. Please note that these are digital images only, and do not contain GIS data files.

Each CD is available for $30.00 (plus $6.00 shipping and handling). Click here for information on how to order.

Geographic Information System (GIS) data files - GIS Files of Official Alquist-Priolo Earthquake Fault Zones (CD 2001-04 – Central Coastal Region, CD 2001-05 – Southern Region, CD 2001-06 – Northern and Eastern Region).
GIS data are provided as MapInfo tab files, ESRI shape files, and dxf export files. To view or use this data, the user must have a GIS software program such as ArcInfo, ArcView, MapInfo, or Intergraph installed on their computer. The GIS data include lines, points, and polygons and are digitized from the original 1:24,000 scale regulatory maps. The CD's are sold separately and, in addition to GIS data, include a digital version of Special Publication 42, Fault-Rupture Zones in California, which explains the AP Act, the zoning program, and associated regulations. Please note that these are GIS data files only, and do not contain image files or base maps.

Each CD is available for $60.00 (plus $6.00 shipping and handling). These CD's are also available as a set at the special price of $150.00, plus $8.00 for shipping and handling. Click here for information on how to order.

Please view the FAQ page if you have questions concerning what coverage you need.