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Tracking Earthquake Cascades The Southern California Earthquake Center, Phase 4 (SCEC4): Tracking Earthquake Cascades Proposal Submitted to National Science Foundation and U.S. Geological Survey March 2010 Project Summary.............................................................................................................i I. Introduction...............................................................................................................1 A. Southern California as a Natural Laboratory...................................................................... 1 B. SCEC as a Virtual Organization......................................................................................... 3 C. Earthquake System Science .............................................................................................. 5 D. Intellectual Merit of the Proposed Research ...................................................................... 5 E. Broader Impacts of the Proposed Research ...................................................................... 6 II. Research Accomplishments....................................................................................7 A. Science Accomplishments ................................................................................................. 7 1. Develop the Unified Structural Representation ............................................................ 8 2. Develop an Extended Earthquake Rupture Forecast................................................. 10 3. Predict Broadband Ground Motions ........................................................................... 17 4. Prepare Post-Earthquake Scientific Response Strategies ......................................... 20 B. Communication, Education & Outreach Accomplishments.............................................. 21 1. 2009 Program Evaluation........................................................................................... 21 2. Major Activities and Results ....................................................................................... 21 C. Information Technology Accomplishments....................................................................... 25 III. SCEC4 Project Plan ................................................................................................27 A. SCEC4 Vision Statement ................................................................................................. 27 B. Science Plan .................................................................................................................... 28 1. Fundamental Problems of Earthquake Physics ......................................................... 29 2. Interdisciplinary Research Initiatives .......................................................................... 41 2. System-Science Challenges and SCEC4 Organization ............................................. 44 C. Communication, Education & Outreach Plan................................................................... 47 1. Implementation Interface............................................................................................ 48 2. Public Education and Preparedness .......................................................................... 49 3. K-14 Earthquake Education Initiative ......................................................................... 51 4. Experiential Learning and Career Advancement........................................................ 52 D. Diversity Plan ................................................................................................................... 53 E. Information Technology Plan............................................................................................ 54 IV. Management Plan ...................................................................................................56 A. Organization of the Center ............................................................................................... 56 B. Budgeting Process ........................................................................................................... 58 C. Operations Following a Major Earthquake ....................................................................... 59 V. References ..............................................................................................................61 Project Summary This proposal requests funding for the Southern California Earthquake Center (SCEC) for the 5-year period from 1 Feb 2012 to 31 Jan 2017 (SCEC4). The Center coordinates basic research in earthquake science using Southern California as its principal natural laboratory. The region is data-rich and, with an urbanized population exceeding 20 million, it comprises the lion’s share of national earthquake risk. Ac- cording to the Uniform California Earthquake Rupture Forecast (UCERF2), the mean probability of an M > 7 earthquake in Southern California over the next 30 years is 82%. New research by the Southern San Andreas Fault Evaluation (SoSAFE) project has revised the recurrence interval for the Carrizo sec- tion of the San Andreas fault downward, to less than the open interval since its last rupture in 1857. The entire southern San Andreas is “locked and loaded.” SCEC Mission. SCEC’s theme of earthquake system science is reflected in its mission statement, which emphasizes the connections between information gathering by sensor networks, fieldwork, and laboratory experiments; knowledge formulation through physics-based, system-level modeling; improved under- standing of seismic hazard; and actions to reduce earthquake risk and promote community resilience. The Center is a large consortium of institutions with a national, and increasingly worldwide, distribution that coordinates earthquake system science within Southern California, and with research elsewhere. The 16 current core institutions have all committed resources to SCEC4, and three new core institutions are expected to join, including a consortium of 6 CalState campuses. More than 50 other institutions (11 for- eign) are likely to participate, forming one of the largest research collaborations in geoscience. Several other characteristics describe the Center: - A collaboratory for earthquake system science that includes the Community Modeling Environ- ment (CME), which applies high-performance computing to large-scale earthquake modeling, and the Collaboratory for the Study of Earthquake Predictability (CSEP), a global infrastructure for the prospective testing of earthquake forecasts. - An open “community of trust” that nurtures stu- dents and early-career scientists and shares in- formation and ideas about how earthquakes work. The Center’s working groups, workshops, field ac- tivities, and annual meeting enable scientists to collaborate over sustained periods, building strong interpersonal networks that promote intellectual exchange and mutual support. About two-thirds of the total SCEC science budget directly supports students and early-career scientists (Fig. S1). - A reliable and trusted partner that collaborates with other organizations in reducing risk and pro- moting societal resilience to earthquake disasters. The SCEC Communication, Education, and Out- reach (CEO) program has steadily grown a di- verse network of partnerships. Its California-wide Earthquake Country Alliance (ECA)—now compris- ing more than 200 organizations—promotes preparedness through the popular publications that have branched from Putting Down Roots in Earthquake Country and involves millions of California citizens in earthquake awareness and readiness exercises through its annual ShakeOut exercises. Intellectual Merit of the Proposed Research. Earthquakes emerge from complex, multiscale interac- tions within active fault systems that are opaque, and are thus difficult to observe. They cascade as cha- otic chain reactions through the natural and built environments, and are thus difficult to predict. The pro- posed 5-year research program will pioneer time-dependent seismic hazard analysis—the geoscience required to track earthquake cascades. This science seeks to understand the unusual physics of how i matter and energy interact during the extreme conditions of rock failure. No theory adequately describes the basic features of dynamic rupture, nor is one available that fully explains the dynamical interactions within networks of faults. Progress towards a comprehensive theory will improve the predictive capabili- ties of earthquake system science. SCEC4 will move this science forward through highly integrated collaborations that are coordinated across scientific disciplines and research institutions and enabled by high-performance computing and advanced information technology. It will focus on six fundamental problems of earthquake physics: a. Stress transfer from plate motion to crustal faults: long-term fault slip rates. b. Stress-mediated fault interactions and earthquake clustering: evaluation of mechanisms. c. Evolution of fault resistance during seismic slip: scale-appropriate laws for rupture modeling. d. Structure and evolution of fault zones and systems: relation to earthquake physics. e. Causes and effects of transient deformations: slow slip events and tectonic tremor. f. Seismic wave generation and scattering: prediction of strong ground motions. Broader Impacts of the Proposed Research. The Center will translate basic research into practical products for reducing risk and improving community resilience in Southern California and elsewhere. The SCEC4 program will help to: - transform
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