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In 1999, the Southern California Earthquake Center had a very active year. As the end of SCEC's formal existence as an NSF Science and Technology Center approaches, a number of activities aimed at maintaining a high level of cooperative organization of the earthquake research community are capturing more and more of the attention of SCEC members. We will be writing a new proposal to NSF and the USGS to fund SCEC activities beyond 2/1/2002 during 2000.
The highlights of SCEC activities for the past year include the following categories, which are described in greater detail in the main body of the report.
1. Continuation and Completion of Planned SCEC Activities:
LARSE II. The Southern California Earthquake Center and the U.S. Geological Survey led a seismic-imaging survey known as the Los Angeles Region Seismic Experiment, Phase II (LARSE II). This involved both an active and passive component along a 100-km-long corridor extending from Santa Monica Bay northward to the western Mojave Desert, (through the 1994 Northridge earthquake epicentral area). This is the first time such a transect has been produced through the entire plate boundary zone. The active component of LARSE II involved deployment of 1400 seismographs at 100-m spacing along the main corridor, with shotpoints approximately 1000 m apart. In addition, several lines (10-20 km in length) at various angles to the main corridor were deployed in the San Fernando Valley and Santa Monica areas. Seismographs along the main corridor and along all cross lines recorded all of the shots. Primary imaging targets include the Santa Monica, San Gabriel, and San Andreas faults, blind thrust faults (including the Northridge fault), and the depths and shapes of the sedimentary basins in the San Fernando Valley and Santa Monica areas. Preliminary results indicate the data are generally quite good, and some are remarkable. For example, several of the very small shots (5-25 lbs) in the Santa Monica area and San Fernando Valley were recorded as far north as the Mojave Desert, 60-80 km away. Travel time and amplitude anomalies are evident in first arrivals near the San Andreas fault, and reflections from the middle and lower crust are apparent in raw shot gathers.
SCIGN. The Southern California Integrated GPS Network (SCIGN) has had a very productive and exciting year, with many new stations coming on-line. We are now well past the midpoint on our way to the goal of 250 continuously operating GPS stations in southern California, and are ready to complete the final major phase of network installation in the year 2000.
In addition, we have collected unprecedented data sets bearing on co-seismic and post-seismic deformations associated with the Hector Mine earthquake.
Taking the long-term view, SCIGN and SCEC have participated in the formation of the California Spatial Reference Center, a new organization that will provide an interface between SCIGN and the Land Surveying profession. This is an important step toward getting the State of California and surveying community involved directly in the use and operation of dense GPS networks.
Phase III Report. A major SCEC activity over the past year pertained to the continued development of the so-called "Phase III" report, wherein site-specific characteristics are incorporated into ground motion estimates and henceforth into the seismic hazard analysis. This effort was described in recent reports, and papers are now in review for collective publication in the Bulletin of the Seismological Society of America in 2000. The set of titles and the description of the contents are provided in the attached annual report.
"Legacy" Document. At the SCEC annual meeting, the SCEC community agreed to proceed with the production of a so-called "legacy" document, wherein SCEC's successes and accomplishments will be summarized. This will be used as a mechanism to focus research during the next two years, in such a way as to come to closure on some of the major SCEC challenges, and to outline a roadmap for the future when it comes to the challenges that are only coming now to the fore. A major question that has arisen as a result of the last decade of research is labeled as "earthquake physics". This is a vast subject, to which SCEC has contributed in the last few years and will continue to contribute in the next few years . It is clear that this is a decadal topic that will not be resolved in the few remaining years of SCEC's formal existence, but which will provide a strong focus for cooperative research in the years to come.
2. Earthquake Response to Major Worldwide 1999 Events:
1999 has been a very important years in terms of severe earthquakes with a large human impact. SCEC has had a leading role in the coordination of the scientific response to such earthquakes, most of which have taken place in areas far remote from southern California. It is of extreme importance to recognize (1) the benefit to SCEC science derived from the study of these earthquakes worldwide, both from the seismological point of view and from the earthquake engineering point of view, and (2) the benefits that the SCEC multi-disciplinary approach has brought to the local studies of these significant events. It is very much to SCEC credit that colleagues worldwide have specifically requested cooperation with SCEC scientists, and have been rewarded with rapid response from the SCEC community, with the support of the major SCEC sponsors. In a way, this experience sets a new standard for worldwide response to significant earthquakes, to the study of the seismological aspects (from seismotectonics, to strong-motions, to fault-zone-trapped waves) of such earthquakes, to the analysis of the damages caused by strong-motions, to the assessment of ongoing seismic hazards, as they might be affected by stress transfer. Because of these earthquakes, 1999 showed, beyond the shadow of a doubt, the importance of studying earthquakes world-wide, even though one's focus remains as small an area as southern California.
The Turkish Izmit and Duzce Earthquakes. The August 17, 1999, M7.8 earthquake was one of the major seismic disasters in recent history. SCEC was assigned the leadership role, in coordination with the USGS, for the US portion of the seismological scientific response to this event. This effort was carefully coordinated with our Turkish colleagues, and comprised a geological and seismotectonic response, a seismological deployment focused on aftershock and post-seismic studies (including fault-zone trapped waves), and a geodetic (GPS) effort targeted at the capture of post-seismic deformations. These efforts are described in the working Group reports. SCEC contributions have been prominent at the 199 Fall AGU meeting. Of special interest is the November 12, 1999 Duzce earthquake, which constitutes a stringent-and somewhat unexpected-test of the simplest current theories of stress transfer and event triggering. SCEC scientists will continue research on this pair of events in the coming year.
The Taiwan Chi-Chi Earthquake. Although SCEC did not have a direct responsibility in the US contribution to the response to the September 22, 1999, M7.6 Chi-Chi (Taiwan) earthquake, several SCEC scientists participated in studies of the event itself, of the strong motions that it generated, and of the rapid response infrastructure that the Taiwanese Government had put in place prior to the event. SCEC will act as a mediator-through the SCEC database infrastructure-between Taiwan and US scientists studying the unique, high quality digital strong motion record collected by the Taiwan network. Several SCEC scientists are participating in international cooperative studies of this event.
The Hector Mine Earthquake. The October 16, 1999, Hector Mines, CA earthquake (M7.1) was clearly in "SCEC's backyard". SCEC took the lead in initiating post-earthquake studies, in collaboration with the USGS, CDMG, and with the support of the US Marine Corps. (The entire extent of the surface rupture lied within the Twenty Nine Palms Marine Base, and no significant studies would have been possible without the active support of the base.) The response involved geological studies, GPS geodetic studies, and a uniquely thorough two-dimensional seismic deployment, that was made possible by the presence of a large number of instruments in southern California, because of the LARSE experiment. In addition, INSAR images using the ESA ERS-2 spacecraft radar were analyzed by SCEC members at UCSD and JPL within 4-days of the event, and images were made available to field geologists in time for them to study the distribution of small cracks and fractures off the main fault, which might have been easily missed otherwise. This constitutes a "first" in post-earthquake response, and demonstrates the unique potential of remote sensing techniques in this respect. Hector Mines studies, as well as studies of earthquakes mentioned earlier, were the object of special sessions at the 1999 Fall meeting of the AGU, and will be the object of special sessions at the upcoming SSA 2000 annual meeting.
3. Leadership in Collaborative Earthquake Research
There is a clear trend in earthquake research worldwide toward collaborative initiatives. SCEC is clearly perceived as a leader institution, and in some cases as a model, in this respect. In some instances, SCEC has been able to act as a direct catalyst for such efforts. In a few instances, SCEC has been able to provide the basic organizational infrastructure, based on previous experience. The major examples are listed below:
WG 2000. After the series of collaborative studies and reports labeled "SCEC Phase I-III" reports, we are ready to proceed with a re-visit of the Phase II report, in the light of the results documented in the Phase III collection of scientific papers. This logical step, that will re-evaluate the Phase II conclusions, will not be a new "consensus" report, but will allow a more flexible format, with a broader outlook. This task has just begun and will be a major focus in 2000.
WInSAR. In recent years, Interferometric Spaceborne Synthetic Aperture Radar (InSAR) has become one of the most spectacular new methods for studying shallow earthquakes. At the present time, the only assets available to scientists are the ESA ERS1/2 spacecraft, and the Canadian RadarSat spacecraft The consequence is that US researchers must purchase the data they need from foreign distributors. This year, a consortium of academic groups, as well as JPL and the USGS (both members of SCEC) has bee created in order to acquire ERS data at an advantageous price from the ESA distributors (SpotImage and EurImage). This consortium turned to SCEC for support, and the Board of Directors approved the formation of a new WInSAR (Western US InSAR) Standing committee, that will coordinate the data acquisition requests on behalf of the community, and will coordinate the purchase of these data. WInSAR is governed by a set of bylaws that have been approved by members and by the SCEC Board. (as is SCIGN, for example). This is viewed as an experiment designed to place INSAR data in the hands of researchers, in a cost-effective fashion. The WInSAR officers have been elected, and the first set of data requests is being processed.
EQ 2000. In 1999, SCEC joined forces with the California Division of Mines and Geology (CDMG), the Pacific Earthquake Engineering Center (PEER), the TRINET project, the USGS, and other collaborative seismological efforts in California, to explore the possibility of initiating a broader, most systematic support by the State of earthquake hazards research in California. This is still in the formative stages, and SCEC intends to continue its efforts at leading such an initiative.
GEM and ACES. General Earthquake Models (GEM) refers to the development of models and numerical simulations of earthquake fault systems, combined with theoretical investigations, space-time pattern analysis and applications to both laboratory and observed data. Numerical simulations pose a major challenge, because earthquakes are a multi-scale problem, involving time scales of hundreds to thousands of years and spatial scales of meters to as much as a thousand km. To advance GEM, SCEC has held a series of workshops throughout the past year, as well as managed a limited amount of seed funding granted by NSF for research. In addition, during January 3February 5, 1999 many members of the US GEM community attended the APEC Cooperation on Earthquake Simulations (ACES) workshop in Brisbane, Australia. Over the past year, we have produced several documents pertaining to the GEM program, and a number of scientific papers are in preparation that have developed as a result of the GEM collaboration. In particular, the forthcoming AGU monograph on "Physics of Earthquakes" will contain over 15 papers, most of which have resulted from GEM efforts. All of these results and more are summarized on the GEM web site: http://geodynamics.jpl.nasa.gov/gem.
EarthScope and PBO. The SCEC community took a very active role in the formulation of the new EarthScope initiative for Major Research Equipment (MRE) funding by the National Science Foundation. In particular, SCEC organized and hosted a major national workshop (with international participation) October 2-5, 1999 in Snowbird, Utah. The focus of this workshop was the "Plate Boundary Observatory" initiative, a major component of EarthScope. This workshop will result in a white paper highlighting the major science issues identified by the participants, which will require major equipment acquisition and deployment and collaborative research over the next decade. Particularly noteworthy was the preparation of a letter to NSF and NASA emphasizing the potential role of INSAR in this context. SCEC anticipates to continue to play a leadership role in developing and refining the framework for PBO over the next few months, and will collaborate with the organizers of other EarthScope components, notably, USArray and SAFOD. SCEC Director Tom Henyey is the chair of the EarthScope Working Group, SCEC Administrative Director John McRaney is the secretary of the group, and Acting Science Director Bernard Minster is (along with Henyey and McRaney) on the Executive Committee of the Working Group.
4. Highlights of the 1999 SCEC Education and Outreach Program
The Real Meaning of Seismic Risk Symposia and Workshops SCEC conducted the first workshop in a series designed to encourage compelling exchanges among earth scientists, earthquake engineers, building officials, public policymakers, architects, insurers, developers and the media. Held in partnership with Los Angeles County Urban Search and Rescue and the Los Angeles City Emergency Planning Commission, who sponsored the event. About 100 people attended the daylong symposium.
1999 Summer Internship Program Ten students from California universities and colleges participated in the program and Intern Colloquium. The colloquium included a day of research update presentations by the interns, and a three day field trip to southern California seismological points of interest, where SCEC Scientists met the group to explain each location. The students presented posters at the SCEC annual meeting. Reports from the interns are available for download on the SCEC Website.
DESC Online Education Modules - SCEC's DESC Online Advisory Group, led by Jill Andrews and Meridith Osterfeld (K12 Alliance), has conducted five meetings and completed the overall design, story line and accompanying lessons and activities for a Middle School level module. The first group of lessons is now in the hands of the Web authors (John Marquis and Maggi Glasscoe). Estimated time to completion of the Middle School modules is mid- to late 2000. This particular curriculum is highly popular among K12 teachers; beta versions presented in annual meetings (i.e., California Science Teachers Association) and workshops (i.e., AGU annual meeting) are enthusiastically received and endorsed by teachers.
SCEC Museum Partnerships SCEC has established ongoing partnerships with several museums: California Science Center, Exposition Park, Los Angeles (Earth Science education programs and exhibits, patron programs); San Francisco's Exploratorium (development and filming of "Faultline," a multi-media, interactive exhibit that "aired" on local TV and the Web in October, 1999 to commemorate the 10th anniversary of the 1989 Loma Prieta earthquake); Riverside County Children's Museum (in partnership with UC Riverside to create an educational, family-oriented exhibit on earthquakes in their region); Santa Barbara Museum of Natural History (to plan a new earth sciences exhibit, with features such as a tour of the Mission Ridge fault, which runs through museum grounds; a walking tour of the surrounding area, which includes the fault scarp, an ancient landslide, and a paleo channel; and a CUBE/REDI computer display); and the Denver Museum of Natural History patrons (led a field trip to a series of local faults and the Caltech-USGS seismic network and seismological laboratory displays in Pasadena).
EQNET This effort is best described by direct examination of the WWW page: see www.eqnet.org. This web page has benefited from extensive revisions to improve greatly search capability.
SCEC Science Seminars Post Earthquake Planning for 50 SCEC-affiliated scientists and students to devise a new plan around scientific objectives of a post-earthquake investigation. HAZUS and Faults of LA an overview of FEMA's National Risk Assessment Tool, HAZUS ("HAZards United States"), by two earthquake engineering consultants who participated in the design and implementation process of the tool, followed by a series of presentations on research on LA fault systems. 90 people attended the seminar (73 were SCEC Scientists).
SCEC Science Workshops, Liquefaction Report, and Accompanying Workshops- SCEC produced and printed a new document to help engineers, geologists, and building officials evaluate and take protective measures against liquefaction hazards in southern California. SCEC and CDMG announced the report through a press conference and subsequent workshop held in April 1999. Over 1000 copies were distributed (sold or given to workshop participants). Liquefaction Workshops were held in June and November in partnership with CDMG to aid practitioners, building officials, decision-makers and others in implementing the new guidelines. 190 people attended the first workshop in June. 95 people attended the second workshop in November.
LARSE Activities SCEC E&O personnel assisted with the Public Awareness, Education, Permitting and Siting process, in coordination with USGS: developed publications, coordinated dissemination and press releases; presentations to local government, civic groups, media. This was a very successful effort, which contributed to a glitch-free execution of the experiment.
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