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United States Department of the Interior Geological Survey UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY NATIONAL EARTHQUAKE HAZARDS REDUCTION PROGRAM, SUMMARIES OF TECHNICAL REPORTS VOLUME XXII Prepared by Participants in NATIONAL EARTHQUAKE HAZARDS REDUCTION PROGRAM July 1986 OPEN-FILE REPORT 86-383 This report (map) is preliminary ancj has not been reviewed for conformity with U.S.Geological Survey editorial standards (and stratigraphic nomenclature). Any use of trade names is for descriptive purposes only and does not imply endorsement by the USGS. Menlo Park, California 1986 UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY NATIONAL EARTHQUAKE HAZARDS REDUCTION PROGRAM, SUMMARIES OF TECHNICAL REPORTS VOLUME XXII Prepared by Participants in NATIONAL EARTHQUAKE HAZARDS REDUCTION PROGRAM Compiled by Muriel L. Jacobson Thelma R. Rodriguez The research results described in the following summaries were submitted by the investigators on May 16, 1985 and cover the 6-months period from October 1, 1985 through May 31, 1986. These reports include both work performed under contracts administered by the Geological Survey and work by members of the Geological Survey. The report summaries are grouped into the three major elements of the National Earthquake Hazards Reduction Program. Open File Report No. 86-383 This report has not been reviewed for conformity with USGS editorial standards and stratigraphic nomenclature. Parts of it were prepared under contract to the U.S. Geological Survey and the opinions and conclusions expressed herein do not necessarily represent those of the USGS. Any use of trade names is for descriptive purposes only and does not imply endorsement by the USGS. The data and interpretations in these progress reports may be reevaluated by the investigators upon completion of the research. Readers who wish to cite findings described herein sfyou}.d confirm their accuracy with tjae author. CONTENTS Earthquake Hazards Reduction Program Page ELEMENT I - Recent Tectonics and Earthquake Potential Determine the tectonic framework and earthquake potential of U.S. seismogenic zones with significant hazard potential. Objective (1-1): Regional seismic monitoring. .................. 1 Objective (I-2): Source zone characteristics Identify and map active crustal faults, using geophysical and geological data to interpret the structure and geometry of seismogenic zones. 1. Identify and map active faults in seismic regions. 2. Combine geophysical and geologic data to interpret tectonic setting of seismogenic zones................... 48 Objective (I-3): Earthquake potential Estimate fault slip rates, earthquake magnitudes, and recurrence intervals for seismogenic zones and faults disclosed by research under Objectives T-1 and T-2, using geological and geophysical data. 1. Earthquake potential estimates for regions of the U.S. west of 100°W. 2. Earthquake potential estimates for regions of the U.S. east of 100°W. 3. Support studies in geochemistry, geology, and soils science that enable fault movements to be accurately dated................................................. 129 ELEMENT II. Earthquake Prediction Research Collect observational data and develop the instrumentation, methodologies, and physical understanding needed to predict damaging earthquakes. Page Objective (11-1): Prediction Methodology and Evaluation Develop methods to provide a rational basis for estimates of increased earthquake potential. Evaluate the relevance of various geophysical, geochemical, and hydrological data for earthquake prediction. 1. Develop, operate and evaluate instrumentation for monitoring potential earthquake precursors. 2. Analyze and evaluate seismicity data collected prior to medium and large earthquakes. 3. Obtain and analyze data from seismically active regions of foreign countries through cooperative projects with the host countries. 4. Systematically evaluate data and develop statistics that relate observations of specific phenomena to earthquake occurrence. 5. Develop, study and test prediction methods that can be used to proceed from estimates of long- range earthquake potential to specific short-term predictions............................................. 202 Objective (II-2): Earthquake Prediction Experiments Conduct data collection and analysis experiments in areas of California capable of great earthquakes, where large populations are at risk. The experiments will emphasize improved coordination of data collection , data reporting, review and analysis according to set schedules and standards. 1. Collect and analyze data for an earthquake prediction experiment in southern California, concentrating on the southern San Andreas fault from Parkfield, California to the Salton Sea. 2. Collect and analyze data for an earthquake prediction experiment in central California, concentrating on the San Andreas fault north of Parkfield, California........ 260 Objective (H-3): Theoretical, Laboratory and Fault Zone Studies Improve our understanding of the physics of earthquake processes through theoretical and laboratory studies to guide and test earth­ quake prediction observations and data analysis. Measure physical properties of those zones selected for earthquake experiments, including stress, temperature, elastic and anelastic characteristics, pore pressure, and material properties. Page 1. Conduct theoretical investigations of failure and pre-failure processes and the nature of large- scale earthquake instability. 2. Conduct experimental studies of the dynamics of faulting and the constitutive properties of fault zone materials. 3. Through the use of drilled holes and appropriate down hole instruments, determine the physical state of the fault zone in regions of earthquake prediction experiments................................. 413 Objective (I I-4): Induced Seismicity Studies Determine the physical mechanism responsible for reservoir-induced seismicity and develop techniques for predicting and mitigating this phenomena. 1. Develop, test, and evaluate theories on the physics of induced seismicity. 2. Develop techniques for predicting the character and severity of induced seismicity. 3. Devise hazard assessment and mitigation strategies at sites of induced seismicity........................... 473 ELEMENT III Evaluation of Regional and Urban Earthquake Hazards Delineate, evaluate, and document earthquake hazards and risk in urban regions at seismic risk. Regions of interest, in order of priority, are: 1) The Wasatch Front 2) Southern California 3) Northern California 4) Anchorage Region 5) Puget Sound 6) Mississippi Valley 7) Charleston Region Objective (HI-1): Establishment of information systems. ....... 480 iii Page Objective (MI-2): Mapping and synthesis of geologic hazards Prepare synthesis documents, maps and develop models on surface faulting, liquefaction potential, ground failure and tectonic deformation.................................... 518 Objective (MI-3): Ground motion modeling Develop and apply techniques for estimating strong ground shaking. ............................................ 537 Objective (IM-4): Loss estimation modeling Develop and apply techniques for estimating earthquake losses...................................................... 542 Objective (MI-5) Implementation............................. ELEMENT IV Earthquake Data and Information Services Objective (IV-1): Install, operate, maintain, and improve standardized networks of seismograph stations and process and provide digital seismic data on magnetic tape to network- day tape format. 1. Operate the WWSSN and GDSN and compile network data from worldwide high quality digital seismic stations. 2. Provide network engineering support. 3. Provide network data review and compilation............ 547 Objective (IV-2): Provide seismological data and information services to the public and to the seismological research community. 1. Maintain and improve a real-time data acquisition system for NEIS. (GSG) 2. Develop dedicated NEIS data-processing capability. 3. Provide earthquake information services. 4. Establish a national earthquake catalogue. .............. 567 IV Page ELEMENT V: Engineering Seismology Objective (V-1): Strong Motion Data Acquisition and Management 1. Operate the national network of strong motion instruments. 2. Deploy specialized arrays of instruments to measure strong ground motion. 3. Deploy specialized arrays of instruments to measure structural response................................. 576 Objective (V-2): Strong Ground Motion Analysis and Theory 1. Infer the physics of earthquake sources. Establish near-source arrays for inferring temporal and spatial variations in the physics of earthquake sources. 2. Study earthquake source and corresponding seismic radiation fields to develop improve ground motion estimates used in engineering and strong-motion seismology. 3. Development of strong ground motion analysis techniques that are applicable for earthquake- resistant design...................................... 589 Index 1: Alphabetized by Principal Investigator Index 2: Alphabetized by Institution........... Most of the technical summaries contained in this volume are for research contracts solicited by RFP-1485. The description in the previous table of contents corresponds to respective Elements and Objectives of that RFP. Additionally some of the summaries are for research objectives that were initiated in earlier years. These objectives are covered in the descriptions found in the following table of contents. Initiated before FY83 Page Earthquake Hazards and Risk Assessment
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