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Borehole-Explosion and Air-Gun Data Acquired in the 2011 Salton Seismic Imaging Project (SSIP), Southern California: Description of the Survey

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Borehole-Explosion and Air-Gun Data Acquired in the 2011 Salton Seismic Imaging Project (SSIP), Southern California: Description of the Survey Borehole-Explosion and Air-Gun Data Acquired in the 2011 Salton Seismic Imaging Project (SSIP), Southern California: Description of the Survey Open-File Report 2013–1172 U.S. Department of the Interior U.S. Geological Survey COVER: High-explosives magazine, used for the Salton Seismic Imaging Program, parked in secured, unused private rodeo ground in Imperial Valley, California. Photo by Gary Fuis. Borehole-Explosion and Air-Gun Data Acquired in the 2011 Salton Seismic Imaging Project (SSIP), Southern California: Description of the Survey By Elizabeth J. Rose, Gary S. Fuis, Joann M. Stock, John A. Hole, Annie M. Kell, Graham Kent, Neal W. Driscoll, Sam Crum, Mark Goldman, Angela M. Reusch, Liang Han, Robert R. Sickler, Rufus D. Catchings, Michael J. Rymer, Coyn J. Criley, Daniel S. Scheirer, Steven M. Skinner, Coye J. Slayday-Criley, Janice M. Murphy, Edward G. Jensen, Robert McClearn, Alex J. Ferguson, Lesley A. Butcher, Max A. Gardner, Iain Emmons, Caleb L. Loughran, Joseph R. Svitek, Patrick C. Bastien, Joseph A. Cotton, David S. Croker, Alistair J. Harding, Jeffrey M. Babcock, Steven H. Harder, and Carla M. Rosa Open-File Report 2013–1172 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2013 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 To order this and other USGS information products, visit http://store.usgs.gov Suggested citation: Rose, E.J., Fuis, G.S., Stock, J.M., Hole, J.A., Kell, A.M., Kent, G., Driscoll, N.W., Crum, S., Goldman, M., Reusch, A.M., Han, L., Sickler, R.R., Catchings, R.D., Rymer, M.J., Criley, C.J., Scheirer, D.S., Skinner, S.M., Slayday-Criley, C.J., Murphy, J.M., Jensen, E.G., McClearn, R., Ferguson, A.J., Butcher, L.A., Gardner, M.A., Emmons, I., Loughran, C.L., Svitek, J.R., Bastien, P.C., Cotton, J.A., Croker, D.S., Harding, A.J., Babcock, J.M., Harder, S.H., and C.M. Rosa, 2013, Borehole-explosion and air-gun data acquired in the 2011 Salton Seismic Imaging Project (SSIP), southern California—Description of the survey: U.S. Geological Survey Open-File Report 2013–1172, 84 p., http://dx.doi.org/10.3133/ofr20131172. 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. ISSN 2331-1258 Contents Introduction ....................................................................................................................................... 1 Geological and Geophysical Setting ................................................................................................. 3 Questions to be Addressed by the Salton Seismic Imaging Project ................................................ 10 Prior Crustal-Structure Work ........................................................................................................... 11 Experiment Design .......................................................................................................................... 11 Division of Labor ............................................................................................................................. 13 Experiment Schedule ...................................................................................................................... 14 Permitting ........................................................................................................................................ 14 Land Shot Size Determination ......................................................................................................... 16 Land Shot Drilling, Loading, and Shooting ...................................................................................... 18 Shot hole description ................................................................................................................... 18 Loading procedures ..................................................................................................................... 24 Shooting Procedures ................................................................................................................... 26 Land Seismometer Deployment ...................................................................................................... 47 Line Scouting, Surveying, Staking, Logging ................................................................................ 47 Instrument Staging ...................................................................................................................... 47 Field Personnel and Training for Instrument Deployment and Pickup ......................................... 50 Instrument Deployment ............................................................................................................... 50 Instrument Pickup ........................................................................................................................ 51 Instrument Downloading .............................................................................................................. 51 Data Processing (Cutting of Record Sections) ............................................................................ 52 Data Archiving ............................................................................................................................. 52 Salton Sea Ocean-Bottom Seismometer Deployment and Air-Gun Operations .............................. 55 Ocean-Bottom Seismometers...................................................................................................... 55 Preparations ............................................................................................................................ 55 General plan for deployment. ................................................................................................... 56 Instrument programming .......................................................................................................... 56 Instrument deployment ............................................................................................................ 56 Instrument pick-up and redeployment ...................................................................................... 56 Air-Gun Operations...................................................................................................................... 56 General Plan for Air-Gun Tracks .............................................................................................. 56 Deployment .............................................................................................................................. 57 Problems .................................................................................................................................. 57 Seismic Acquisition Systems........................................................................................................... 57 Data Processing .............................................................................................................................. 57 Shot Site Remediation .................................................................................................................... 72 KMZ Summary Files ........................................................................................................................ 75 Acknowledgments ........................................................................................................................... 75 References Cited ............................................................................................................................ 75 Appendix I. Drill logs ...................................................................................................................... 84 Appendix II. Drill sample inventory ................................................................................................. 84 Appendix III. Land seismometer locations ...................................................................................... 84 Appendix IV. OBS locations ........................................................................................................... 84 Appendix V. Air gun shot times and locations (complete list) ......................................................... 84 iii Appendix VI. Data supplied to PIs by IRIS ..................................................................................... 84 Appendix VII. SSIP KMZ files (for use in Google EarthTM) ............................................................. 84 Appendix VIII. Full datasets for tables 1–10 ................................................................................... 84 Figures 1a. Shaded relief map of southeastern California showing faults, including the boundary between the Pacific and North American Plates and the Salton Buttes volcanoes. ................. 3 1b. Shaded relief map of southeastern California showing the Salton Seismic Imaging Project. ..... 4 2. Tectonic map of the Gulf of California and Salton Trough, emphasizing
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