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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 Bernard Minster SCEC Annual meeting, 2000
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/002 SCEC and its Mission The Southern California Earthquake Center’s mission is to promote earthquake loss reduction by: –Defining when and where future damaging earthquakes will occur in Southern California, –Calculating the expected ground motions, and –Communicating this information to the public.
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/003 SCEC Objectives To estimate the earthquake potential, or the probability of earthquake occurrence as a function of location, magnitude, and time, To advance our understanding of earthquake rupture dynamics and source physics, To understand the nature of wave propagation through complex geology, To predict ground motions, or complete theoretical seismograms, at any site from plausible future damaging earthquakes, and To transfer this knowledge to communities of end users.
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/004 Master Model "… the goal of SCEC is to integrate research findings from various disciplines in earthquake-related science to develop a prototype probabilistic seismic hazard model (master model) for southern California.” (Keiiti Aki, 1989)
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/005
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/006 Larger Earthquakes 1932–1997
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/007 Earthquake Risk in Southern California 20 Million people + 7th largest economy + Active plate boundary + Over 300 active faults = _____________________________ Almost half the national earthquake risk: 25% in Los Angeles County alone
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/008 Seismicity of Southern California
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/009 GPS Velocity Map of Southern California
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0010 Southern California Integrated GPS Network (SCIGN) 168 stations installed 78 more to be installed (by late 2000)… Total of 250 stations
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0011 GPS in the Los Angeles Basin The Los Angeles basin is being squeezed closed (e.g., Palos Verdes is moving towards JPL).
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0012
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0013 Integration of GPS into Risk Estimation
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0014
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0015 Regional stress changes caused by the Landers, Big Bear and Joshua Tree earthquakes. Areas in red are regions where nearby faults are brought closer to failure. Note that segments of the San Andreas fault pass through red zones. From R.S. Stein, G.C.P. King and J. Lin (Science, 1992), G.C.P. King, R.S. Stein and J. Lin [BSSA, 1994)
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0016 Evidence for Fault Zone Healing following the 1992 Landers Earthquake from Fault Zone Trapped Waves and Body Waves. Left Panel: Shot points (SP-X) and receiver locations (Lines 1 and 3) along Johnson Valley segment. Center Panels: Time differences in arriving phases between 1994 and 1996 as a function of distance from the fault trace along Line 1. Right Panels: Time differences in arriving phases between 1996 and 1998 as a function of distance from the fault trace along Line 1. (From Li, 2000)
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0017 The probability of a large earthquake on the San Bernardino segment of the San Andreas fault was increased by the 1992 Landers and 1999 Hector Mine earthquakes.
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0018 Top panel: Surface projections of major fault systems of the Los Angeles area. Edges with triangles represent the “tops” of the fault planes – solid if the fault breaks the surface and hollow if the fault is buried. The opposite edge of each fault system mapped above represents the “bottom” of the fault plane which is generally 10-15 km deep. Black areas are the surfaces which moved during earthquakes (including the black line on the near- vertical San Andreas fault). The magnitude listed is for a hypothetical earthquake which breaks the entire fault system. Bottom panel: 51 potential moderate (M6.5-M6.8) earthquakes on the major fault systems. Numbers denote the recurrence intervals for earthquakes in each section.
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0019 Sub-Surface Fault Map of the Los Angeles Area (Dolan, 2000)
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0020 Our Best Guess Fault Map of the Greater Los Angeles Basin
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0021 Paleoseismology and Structure of a Blind Thrust Fault from Geomorphology and Marine Terrace Dating. Left Panel: Geology of the San Joaquin Hills uplift along a left-step in the Newport-Inglewood fault. Right Panel: Model of the San Joaquin Hills blind thrust fault. From Grant, 1999
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0022 Seismic reflection survey across oil fields Seismicity analysis
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0023 The Puente Hills Blind Thrust Fault and 1987 Whittier Narrows Earthquake Sequence
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0024 SCEC Phase III Report An investigation of how and if site effects can be accounted for in probabilistic seismic hazard analysis (PSHA) in southern California Conclusions: 1) Detailed classification (beyond rock versus soil) is justified with the Wills et al. (2000) map. 2) Basin depth is a significant factor, even for PGA (but may be a proxy). 3) Uncertainty (sigma) remains high after site corrections.
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0025 Deterministic Ground Motion Prediction: Input to Performance-based Engineering Design
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0026 Los Angeles Regional Seismic Experiment LARSE Top panel: Crustal structure image across the Los Angeles basin and San Gabriel Mountains from seismic transect. Bottom panel: Interpretation of fault structure based on data from top panel.
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0027 LARSE II Transect from Santa Monica Bay to the Mojave Desert Features crossed include: Santa Monica Fault Santa Monica Buried Thrust Fault Santa Monica Mountains San Fernando Valley/Basin 1994 Northridge Earthquake Fault Santa Susana Thrust Fault Santa Susana Mountains San Gabriel Fault Central Transverse Ranges San Andreas Fault Mojave Block Garlock Fault Tehachapi Mountains
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0028 A USGS - SCEC Cooperative Project: LA Region Seismic Experiment II SCEC and USGS conducted the seismic imaging survey of the Los Angeles region in October 1999 as part of The National Earthquake Hazards Reduction Program.
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0029 Fence Diagram from the SCEC Seismic Velocity Model of Southern California
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0030 The Basin-edge Effect from the 1994 Northridge Earthquake
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0031 Simulating Dynamics of Fault Rupture Tough computational problem because... Inner scales are small: < 10 meter <.01 second Outer scales are large: > 100 kilometers > 100 years +46
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0032 Critical Point Model The largest earthquake on a given fault network is possible only when the network is in a critical state. The crust is not in a continual critical state. Earthquake cycles can be viewed as repeated approaches and retreats from the critical state. The critical state is characterized by spatial stress correlations at all scales up to the size of the regional fault network. A large earthquake destroys the stress correlation on its regional fault network, producing a quiescent period for intermediate and large events. Small earthquakes rebuild stress correlation, making the next large earthquake possible. Each earthquake roughens the stress field at longer wavelengths and smoothes it at shorter ones.
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0033
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0034 Simulations for the San Andreas Fault (Olsen, 2000)
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0035
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0036 Products and Mechanisms for Dissemination Products Level 1 Fact Sheets/Maps/Videos FAQs/Interviews Reprints/Press Releases Working Group Reports Newsletters “Roots” Updates Level 2 Consensus Documents Annual Reports Proceedings Maps/Databases Phase “N” “Glossy” Brochures SCEC Science (Results and Processes) Dissemination Mechanisms Workshops/Seminars Short Courses Web Pages Education Modules Partnerships Mailings/E-mail Lists Exhibits Curriculum Development Speaker’s Bureau Press Conferences Internships Field Trips Evaluation / Follow Through Mechanisms (Our activities as well as those of our partners which are based on our products) Workshops Short Courses Surveys Social Science Studies Policies Enacted Partnerships
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0037 Collaboration between Earth Scientists and Engineers
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0038 Partners in Academia National 2 SCEC Institutions: Columbia; UNR Carnegi-Mellon Central WA University GA Institute of Technology Harvard, MIT, NAU, OSU,Texas Tech Univ., U of AK, U of CO, U of DE, U of Memphis (CERI), U of WA, U of NM, Woods Hole Oceanographic Inst., Univ of Utah DLESE MCEER MAE International IRIS, EERI CICESE, Mexico Institute de Physique du Globe, Paris Univ of Athens & Thessaloniki, Greece Istituto Nazionale de Geofisica, Rome State Seismology Bureau, China Building Research Institute, Japan Disaster Prevention Research Institute, Kyoto, Japan Geological Surveys of Canada, Japan Univ of Tokyo Earthquake Research Institute State 7 SCEC Institutions: Caltech; UC San Diego, Davis, Santa Barbara, Los Angeles; USC; SDSU CSUN, CSULB, UC Berkeley, SFSU, Stanford, UC Irvine, CS Fullerton, CSULA, Whittier College PEER CUREe
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0039 Partners in Education (980) IRIS (E-3 Project, middle school education modules support DLESE (E-3 Project, digital libraries community involvement) Museums (earth science / earthquake exhibits, docent training, educational curricula, hands-on activities, field trips) LACOE (earth science curricula) ARC (earth science curricula) IBHS (Seismic Sleuths video) AGU, FEMA (Seismic Sleuths curriculum revisions) SCEC Community of Researchers, Students USGS (Civic presentations; web-based curricula; K-12 products) PEER (interns) CUREe (Woodframe Project, Engineering/Science Symposia, HAZUS, E-3 Project) California K12 Alliance (education modules creation and review)
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0040 Partners in Government State (230) CA Div Mines & Geology CA OES CA Seismic Safety Commission NV Bureau Mines & Geology Federal (328) USGS FEMA / NEP National Labs: NASA’s JPL, Lawrence Livermore, Los Alamos Local (679) Cities and Counties of southern California: Building Officials Emergency Planners & Responders Urban Planners Public Utilities (water, power)
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0041 Partners in Industry (For-profit, Non-profit) Nonprofit (150) Insurance Education Association CA Assoc. of Insurance Professionals SEAOSC American Red Cross BICEPP Assoc. of Contingency Planners California Earthquake Authority EERI EPARR (Emerg. Prep. Response & Recovery Committee) Private/For-profit (2538) Insurers & Reinsurers Institute for Business & Home Safety Risk Analysis Consultants Design, Engineering Consultants Geotechnical Consultants Contingency Planning Consultants Media Organizations
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0042 SCEC Webservices www.scec.org www.scecdc.scec.org ~4,500 Visitors per week 1200 view Outreach 1000 view INSTANeT News 1000 view Research 300 view worldwide Eq’s 300 view “About SCEC” ~250,000 Visitors per week
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0043 “Putting Down Roots in Earthquake Country” a USGS-SCEC Product Largely funded by USGS Produced by SCEC Outreach 1.8 million distributed by SCEC, USGS, local community Featured on local TV, at earthquake fairs each April
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0044 SCEC Transition Process Funding as NSF S&T Center ends 02/02 – STC funding base: $1.4M – Cannot be renewed under STC Program Joint proposal to NSF/EAR and USGS to be submitted in 12/00 Transition objectives – Strengthen partnership with USGS – Tie in with NSF EarthScope initiatives – Increase integrated, system-level studies of earthquake phenomena – Augment strong Education & Outreach program
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S OUTHERN C ALIFORNIA E ARTHQUAKE C ENTER SCEC: Decade 1 9/18/0045 The Beginning!
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