SPECIAL PUBLICATION 42 Interim Revision 2007 FAULT-RUPTURE HAZARD ZONES IN CALIFORNIA Alquist-Priolo Earthquake Fault Zoning Act 1 with Index to Earthquake Fault Zones Maps 1 Name changed from Special Studies Zones January 1, 1994 DEPARTMENT OF CONSERVATION California Geological Survey STATE OF CALIFORNIA ARNOLD SCHWARZENEGGER GOVERNOR THE RESOURCES AGENCY DEPARTMENT OF CONSERVATION MIKE CHRISMAN BRIDGETT LUTHER SECRETARY FOR RESOURCES DIRECTOR CALIFORNIA GEOLOGICAL SURVEY JOHN G. PARRISH, PH.D. STATE GEOLOGIST SPECIAL PUBLICATION 42 FAULT-RUPTURE HAZARD ZONES IN CALIFORNIA Alquist-Priolo Earthquake Fault Zoning Act With Index to Earthquake Fault Zones Maps by WILLIAM A. BRYANT and EARL W. HART Geologists Interim Revision 2007 California Department of Conservation California Geological Survey 801 K Street, MS 12-31 Sacramento, California 95814 PREFACE The purpose of the Alquist-Priolo Earthquake Fault Zoning Act is to regulate development near active faults so as to mitigate the hazard of surface fault rupture. This report summarizes the various responsibilities under the Act and details the actions taken by the State Geologist and his staff to implement the Act. This is the eleventh revision of Special Publication 42, which was first issued in December 1973 as an “Index to Maps of Special Studies Zones.” A text was added in 1975 and subsequent revisions were made in 1976, 1977, 1980, 1985, 1988, 1990, 1992, 1994, and 1997. The 2007 revision is an interim version, available in electronic format only, that has been updated to reflect changes in the index map and listing of additional affected cities. In response to requests from various users of Alquist-Priolo maps and reports, several digital products are now available, including digital raster graphic (pdf) and Geographic Information System (GIS) files of the Earthquake Fault Zones maps, and digital files of Fault Evaluation Reports and site reports submitted to the California Geological Survey in compliance with the Alquist-Priolo Act (see Appendix E). On January 1, 1994, the name of the Alquist-Priolo Special Studies Zones Act was changed to the Alquist-Priolo Earthquake Fault Zoning Act, and the name Special Studies Zones was changed to Earthquake Fault Zones as a result of a July 25, 1993 amendment. Information on new and revised Earthquake Fault Zones maps will be provided as supplements until the next revision of this report. CALIFORNIA DEPARTMENT OF CONSERVATION CALIFORNIA GEOLOGICAL SURVEY 801 K Street, MS 12-31 Sacramento, CA 95814-3531 www.conservation.ca.gov/cgs PUBLIC INFORMATION OFFICES: SACRAMENTO AREA SAN FRANCISCO AREA LOS ANGELES AREA Publications and Information 345 Middlefield Road, MS 520 888 South Figueroa, Suite 475 801 K Street, MS 14-33 Menlo Park, CA 94025 Los Angeles, CA 90017 Sacramento, CA 95814-3532 (650) 688-6327 (213) 239-0878 (916) 445-5716 SUPPLEMENT NO. 1 TO SPECIAL PUBLICATION 42 (2007 Interim Edition) NEW AND REVISED OFFICIAL MAPS OF EARTHQUAKE FAULT ZONES OF SEPTEMBER 21, 2012 Official Maps of new and revised Earthquake Fault Zones, indexed hereon, are issued pursuant to the Alquist-Priolo Earthquake Fault Zoning Act. Revised maps supersede earlier Official Maps. Copies of these maps may be examined at the offices of affected cities and counties, at the Public Information offices of the California Geological Survey (CGS), and on the CGS website (http://www.quake.ca.gov/gmaps/ap/ap_maps.htm). Both GIS and pdf files can be downloaded from this website. Printed maps may be purchased from ARC-Bryant (formerly BPS Reprographic Services), 945 Bryant Street, San Francisco, California 94103, telephone (415) 495-8700. For information on Official Maps of Earthquake Fault Zones previously issued, and for provisions of the Alquist-Priolo Earthquake Fault Zoning Act, the reader should consult the 2007 edition of Special Publication 42, “Fault-rupture Hazard Zones in California.” This publication is available online only from the California Geological Survey at ftp://ftp.consrv.ca.gov/pub/dmg/pubs/sp/Sp42.pdf. Official Maps issued September 21, 2012 (Map numbers keyed to index map): 1. Hayward.* 6. Salton* 11. Coyote Wells 2. Piru 7. Durmid* 12. Yuha Basin 3. Mecca* 8. Carrizo Mtn.* 13. Mount Signal 4. Mortmar* 9. Painted Gorge 5. Orocopia Canyon* 10. Plaster City _______________ * Revised zone map Cities and counties affected by new or revised Earthquake Fault Zones shown on Official Maps of September 19, 2012: Cities Counties Hayward Alameda Oakland Imperial San Leandro Riverside San Diego Ventura Kern Contra Costa Ventura Los 1 2 Angeles Alameda San Mateo Santa Clara Riverside 3 4 5 6 7 San Diego Imperial 8 9 10 11 12 13 SUPPLEMENT NO. 1 INDEX MAP NEW AND REVISED OFFICIAL MAPS OF EARTHQUAKE FAULT ZONES OF SEPTEMBER 21, 2012 (See List for Names of Maps) CALIFORNIA DEPARTMENT OF CONSERVATION CALIFORNIA GEOLOGICAL SURVEY 801 K Street, MS 12-30 Sacramento, CA 95814-3531 www.conservation.ca.gov/cgs PUBLIC INFORMATION OFFICES: SACRAMENTO AREA SAN FRANCISCO AREA LOS ANGELES AREA Publications and Information 345 Middlefield Road, MS 520 320 W. 4th St., suite 850 801 K Street, MS 14-34 Menlo Park, CA 94025 Los Angeles, CA 90013 Sacramento, CA 95814-3532 (650) 688-6327 (213) 239-0878 (916) 327-1850 SUPPLEMENT NO. 2 TO SPECIAL PUBLICATION 42 (2007 Interim Edition) NEW AND REVISED OFFICIAL MAPS OF EARTHQUAKE FAULT ZONES OF NOVEMBER 6, 2014 Official Maps of new and revised Earthquake Fault Zones, indexed hereon, are issued pursuant to the Alquist-Priolo Earthquake Fault Zoning Act. Revised maps supersede earlier Official Maps. Copies of these maps may be examined at the offices of affected cities and counties, at the Public Information offices of the California Geological Survey (CGS), and on the CGS website (http://www.conservation.ca.gov/CGS/Pages/Index.aspx). Both GIS and pdf files can be downloaded from this website. For information on Official Maps of Earthquake Fault Zones previously issued, and for provisions of the Alquist-Priolo Earthquake Fault Zoning Act, the reader should consult the 2007 edition of Special Publication 42, “Fault-rupture Hazard Zones in California.” This publication is available online only from the California Geological Survey at ftp://ftp.consrv.ca.gov/pub/dmg/pubs/sp/Sp42.pdf. Official Maps issued November 6, 2014 (Map numbers keyed to index map): 1. Hollywood.* 2. Azusa _______________ * Revised zone map Cities and counties affected by new or revised Earthquake Fault Zones shown on Official Maps of November 6, 2014: Cities Counties Azusa Los Angeles Bradbury Duarte Glendora Irwindale Los Angeles Monrovia West Hollywood SUPPLEMENT NO.2 INDEX MAP NEW AND REVISED OFFICIAL MAPS OF EARTHQUAKE FAULT ZONES OF NOVEMBER 6, 2014 (See List for Names of Maps) CONTENTS INTRODUCTION ........................................................................................................................................... 1 PROGRAM FOR ZONING AND EVALUATING FAULTS ........................................................................... 2 Requirements of the Act ......................................................................................................................................... 2 Initial Program for Zoning Faults ............................................................................................................................. 2 Definitions, Policies, Rationale ................................................................................................................................ 3 Fault and Fault Zone ........................................................................................................................................ 3 Fault Trace ....................................................................................................................................................... 5 Active Fault ...................................................................................................................................................... 5 Potentially Active Fault..................................................................................................................................... 5 Sufficiently Active and Well-Defined ................................................................................................................ 5 Delineating the Earthquake Fault Zones ................................................................................................................. 6 Fault Evaluation and Zoning Program ..................................................................................................................... 6 Uses and Limitations of Earthquake Fault Zones Maps .......................................................................................... 9 INDEX TO MAPS OF EARTHQUAKE FAULT ZONES ............................................................................... 9 Availability of Earthquake Fault Zones Maps .......................................................................................................... 9 REFERENCES ............................................................................................................................................. 10 APPENDICES .............................................................................................................................................. 22 Appendix A. Alquist-Priolo Earthquake Fault Zoning Act ..................................................................................... 22 Appendix B. Policies and Criteria of the State Mining and Geology