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USGS Open-File Report 2010-1152 USGS Tsunami Source Working Group (TSWG) Program and Abstracts of the Second Tsunami Source Workshop: July 19–20, 2010 Compiled by W.H.K. Lee, S.H. Kirby, and M.F. Diggles Open-File Report 2010-1152 U.S. Department of the 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 2010 For product and ordering information: World Wide Web: http://www.usgs.gov/pubprod Telephone: 1-888-ASK-USGS For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment: World Wide Web: http://www.usgs.gov Telephone: 1-888-ASK-USGS Suggested citation Lee, W.H.K., Kirby, S.H., and Diggles, M.F., compilers, 2010, Program and abstracts of the Second Tsunami Source Workshop; July 19-20, 2010: U.S. Geological Survey Open-File Report 2010-1152, 33 p. [http://pubs.usgs.gov/of/2010/1152/]. The abstracts by non-USGS authors in this volume are published as they were submitted. Abstracts authored entirely by non-USGS authors do not represent the views or position of the U.S. Geological Survey or the U.S. government and are published solely as part of the Proceedings volume. 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. Contents Introduction, by W.H.K. Lee, S.H. Kirby, and M.F. Diggles................................................................1 Reference .....................................................................................................................................2 Scientific Program for the Second Tsunami Source Workshop..........................................................3 List of Participants in the 2nd Tsunami Source Workshop, July 19-20, 2010....................................5 Abstracts for The Second Tsunami Source Workshop......................................................................7 1. Comparing the Contrasting Rock Frameworks of the Sumatra and South-Central Chile Convergent Margins — Insights Gained About the Sediment Subduction Setting of Great and Giant Megathrust Ruptures, by David W. Scholl .................................................8 2. The 2010 Great Chilean Earthquake and Modern Geophysical Data, by Roland von Huene .........................................................................................................10 3. Revisiting the 1960 Chilean Earthquake, by Hiroo Kanamori......................................................11 4. Selecting a Scientifically Defensible Aleutian Megathrust Rupture for the Multi-Hazards Demonstration Project Tsunami Scenario, by Holly Ryan and the Tsunami Source Working Group....................................................................................................................13 5. Forearc Geology from Free-Air Gravity—Implications for Coseismic Slip During the 2010, 1985, and 1960 Chile Earthquakes, by Richard Blakely, Ray Wells, and Katie Keranen.....................................................................................................................15 6. Tsunami Edge Waves in Relation to the 2010 Chile Earthquake, by Eric Geist..........................16 7. Earthquake Source Characterization for Tsunami Warning, by Barry F Hirshorn and Stuart Weinstein .................................................................................................................18 8. Tsunami Probability in the Caribbean Region, by Tom Parsons and Eric L. Geist......................20 9. Large Off-trench Earthquakes and Their Tsunami Potentials, by Stephen Kirby, Jakob Wartman, and George Choy ....................................................................................21 10. Reliable Earthquake Location Using Grid-Search and Simplex Algorithm, by W.H.K. Lee.....................................................................................................................23 11. Anomalous Es/Mo Earthquakes: Trends and Exceptions to the Trends, by George L. Choy and Stephen H. Kirby ..........................................................................25 12. The USGS Seismic Data Library in Menlo Park, by Willie Lee and Steve Walter .....................27 13. Comparisons of Near-Field Tsunami Characteristics of Giant (M>9) Earthquakes in Chile (1960), Alaska (1964), and Sumatra (2004), by George Plafker and J.C. Savage ...................................................................................29 14. Development Of New Databases For Tsunami Hazard Analysis In California, by Rick I. Wilson, Aggeliki Barberopoulou, Jose C. Borrero, William A. Bryant, Lori A. Dengler, James D. Goltz, Mark R. Legg, Terilee McGuire, Kevin M. Miller, Charles R. Real, Costas E. Synolakis, and Burak Uslu......................................................31 15. New Maximum Tsunami Inundation Maps for Use by Local Emergency Planners in the State of California, USA, by Rick I. Wilson, Aggeliki Barberopoulou, Kevin M. Miller, Jim D. Goltz, and Costas E. Synolakis......................................................32 16. The 2010 Chilean Tsunami on the California Coastline, by Rick I. Wilson, Lori A. Dengler, Mark R. Legg, Kate Long, and Kevin M. Miller .........................................33 iii This page intentionally left blank Program and Abstracts of the Second Tsunami Source Workshop: July 19-20, 2010 Compiled by W.H.K. Lee, S.H. Kirby, and M.F. Diggles Introduction In response to a request by the National Oceanic and Atmospheric Administration (NOAA) for computing tsunami propagations in the western Pacific, Eric Geist asked Willie Lee for assistance in providing parameters of earthquakes which may be future tsunami sources. The U.S. Geological Survey (USGS) Tsunami Source Working Group (TSWG) was initiated in August 2005. An ad hoc group of diverse expertise was formed, with Steve Kirby as the leader. The founding members are: Rick Blakely, Eric Geist, Steve Kirby, Willie Lee, George Plafker, Dave Scholl, Roland von Huene, and Ray Wells. Half of the founding members are USGS emeritus scientists. A report was quickly completed because of NOAA’s urgent need to precalculate tsunami propagation paths for early warning purposes (Kirby and others, 2005). It was clear to the group that much more work needed to be done to improve our knowledge about tsunami sources worldwide. The group therefore started an informal research program on tsunami sources and meets irregularly to share ideas, data, and results. Because our group activities are open to anyone, we have more participants now, including, for example, Harley Benz and George Choy (USGS, Golden, Colo.), Holly Ryan and Stephanie Ross (USGS, Menlo Park, Calif.), Hiroo Kanamori (Caltech), Emile Okal (Northwestern University), and Gerard Fryer and Barry Hirshorn (Pacific Tsunami Warning Center, Hawaii). All participants automatically become “members,” and if anyone is interested, just send an email to Willie Lee at: [email protected] for inclusion in our membership list. To celebrate the fifth anniversary of the TSWG, a workshop is being held in the Auditorium of Building 3, USGS, Menlo Park, on July 19-20, 2010 (Willie Lee and Steve Kirby, Conveners). All talks (except one) will be video broadcast. The first tsunami source workshop was held in April 2006 with about 100 participants from many institutions. This second workshop (on a much smaller scale) will be devoted primarily to recent work by the USGS members. In addition, Hiroo Kanamori (Caltech) will present his recent work on the 1960 and 2010 Chile earthquakes, Barry Hirshorn and Stuart Weinstein (Pacific Tsunami Warning Center) will present their work on tsunami warning, and Rick Wilson (California Geological Survey) will display three posters on tsunami studies by him and his colleagues. Reference Kirby, S., Geist, E., Lee, W.H.K., Scholl, D., and Blakely R., 2005, Tsunami source characterization for western Pacific subduction zones; a preliminary report, prepared at the request of the National Oceanic and Atmospheric Administration for their Tsunami Hazards Reduction Program: U.S. Geological Survey Administrative Report. 2 Scientific Program for the Second Tsunami Source Workshop Willie Lee and Steve Kirby, Conveners July 19, 2010 (Monday Afternoon) 1:30 – 1:35 Tom Brocher (Director, USGS Earthquake Science Center): Welcome 1:35 – 1:45 Steve Kirby and Willie Lee (USGS): Introduction to the USGS Tsunami Source Working Group. 1:45 – 2:15 Dave Scholl (USGS): Comparing the contrasting rock frameworks of the Sumatra and south- central Chile convergent margins—insights gained about the sediment subduction setting of great and giant megathrust ruptures. 2:15– 2:45 Roland von Huene (USGS): Subducted ocean crustal relief bracketing the 2010 Chilean earthquake rupture, implications for large earthquake ruptures. 2:45 – 3:30 Poster viewing and Break. 3:30 – 4:30 Special Earthquake Seminar by Hiroo Kanamori (Caltech): Revisiting the 1960 Chilean earthquake (for a general geoscience audience). July 20, 2010 (Tuesday) 9:00 – 9:30 Holly Ryan (USGS): Selecting a scientifically defensible Aleutian megathrust rupture for the Multi-hazards Demonstration Project tsunami scenario (by Ryan & TSWG). 9:30 – 10:00 Rick Blakely (USGS): Forearc geology from free-air gravity: implications for
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