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Prepared in cooperation with the California Geological Survey; University of Oregon; University of Colorado; University of California, San Diego; and Jet Propulsion Laboratory, California Institute of Technology. Triggered Surface Slips in Southern California Associated with the 2010 El Mayor-Cucapah, Baja California, Mexico, Earthquake SALTON SEA Open-File Report 2010-1333 Jointly published as California Geological Survey Special Report 221 U.S. Department of Interior U.S. Geological Survey COVER Landsat satellite image (LE70390372003084EDC00) showing location of surface slip triggered along faults in the greater Salton Trough area. Red bars show the generalized location of 2010 surface slip along faults in the central Salton Trough and many additional faults in the southwestern section of the Salton Trough. Surface slip in the central Salton Trough shown only where verified in the field; slip in the southwestern section of the Salton Trough shown where verified in the field or inferred from UAVSAR images. Triggered Surface Slips in Southern California Associated with the 2010 El Mayor-Cucapah, Baja California, Mexico, Earthquake By Michael J. Rymer, Jerome A. Treiman, Katherine J. Kendrick, James J. Lienkaemper, Ray J. Weldon, Roger Bilham, Meng Wei, Eric J. Fielding, Janis L. Hernandez, Brian P. E. Olson, Pamela J. Irvine, Nichole Knepprath, Robert R. Sickler, Xiaopeng Tong, and Martin E. Siem Prepared in cooperation with the California Geological Survey; University of Oregon; University of Colorado; University of California, San Diego; and Jet Propulsion Laboratory, California Institute of Technology. Open-File Report 2010–1333 Jointly published as California Geological Survey Special Report 221 U.S. Department of Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Virginia: 2011 This report and any updates to it are available online at: http://pubs.usgs.gov/of/2010/1333/ For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod Suggested citation: Rymer, M.J., Treiman, J.A., Kendrick, K.J., Lienkaemper, J.J., Weldon, R.J., Bilham, R., Wei, M., Fielding, E.J., Hernandez, J.L., Olson, B.P.E., Irvine, P.J., Knepprath, N., Sickler, R.R., Tong, .X., and Siem, M.E., 2011, Triggered surface slips in southern California associated with the 2010 El Mayor-Cucapah, Baja California, Mexico, earthquake: U.S. Geological Survey Open-File Report 2010-1333 and California Geological Survey Special Report 221, 62 p., available at http://pubs.usgs.gov/of/ 2010/1333/. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted material contained within this report. iii Contents Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................1 Timing of Fault Slip .........................................................................................................................................2 Methods...........................................................................................................................................................2 San Andreas Fault..........................................................................................................................................6 Discussion ..............................................................................................................................................6 Coyote Creek Fault .........................................................................................................................................6 Discussion ..............................................................................................................................................6 Superstition Hills Fault ................................................................................................................................11 Discussion ............................................................................................................................................13 Wienert Fault ................................................................................................................................................13 Discussion ............................................................................................................................................13 Superstition Mountain Fault .......................................................................................................................13 Kalin Fault ......................................................................................................................................................13 Discussion ............................................................................................................................................13 Imperial Fault ................................................................................................................................................15 Discussion ............................................................................................................................................15 Brawley Fault Zone ......................................................................................................................................18 Discussion ............................................................................................................................................18 Faults in the Yuha Desert Area ..................................................................................................................19 Northern Centinela Fault Zone .........................................................................................................25 Discussion ...................................................................................................................................25 Faults South of Pinto Wash ...............................................................................................................25 Discussion ...................................................................................................................................25 Yuha Fault .............................................................................................................................................25 Discussion ...................................................................................................................................25 Laguna Salada Fault, East Branch ...................................................................................................32 Discussion ...................................................................................................................................32 Laguna Salada Fault, West Branch .................................................................................................32 Discussion ...................................................................................................................................32 Yuha Well Fault Zone ..........................................................................................................................32 Discussion ...................................................................................................................................37 June 14 Mw5.7 Aftershock ..........................................................................................................................37 Ocotillo Fault Zone ..............................................................................................................................37 Ocotillo Fault ...............................................................................................................................37 Discussion ..........................................................................................................................41 Laguna Salada Fault, Northwest Extension ...................................................................................41 Discussion ...................................................................................................................................41 Elsinore Fault Zone .............................................................................................................................41 Discussion ...................................................................................................................................43 Other Faults ...................................................................................................................................................43 iv Timing of Triggered Slip in the Yuha Desert Area ...................................................................................47 Acknowledgments .......................................................................................................................................47
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