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Marilyn P. Maccabe, Editor U.S. Geological Survey 345 Middlefield EARTHQUAKE HAZARDS REDUCTION PROGRAM PROJECT SUMMARIES - 1979-80 Marilyn P. MacCabe, Editor U.S. Geological Survey 345 Middlefield Road Menlo Park, California 94025 Open-File Report 81-41 This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey standards Any use of trade names is for descriptive purposes only and does not imply endorsement by the USGS CONTENTS Introduction ........................... 1 Highlights of Major Accomplishments .................. 2 Earthquake Hazards ....................... 2 Earthquake Prediction ...................... 5 Global Seismology ........................ 7 Induced Seismicity ........................ 9 Project Summaries .......................... 10 Earthquake Hazards Studies .................... 10 Earthquake potential ..................... 10 Tectonic framework, Quaternary geology, and active faults . 10 California ...................... 10 Western U.S. (excluding California) ........... 21 Eastern U.S. ..................... 31 National ...................... 34 Earthquake recurrence and age dating .............. 35 Earthquake effects ...................... 41 Ground Motion .............. ....... 41 Ground failure ...................... 51 Surface faulting ..................... 54 Post-earthquake studies .................. 55 Earthquake losses ...................... 55 Transfer of Research Findings ................. 56 Earthquake Prediction Studies ................... 57 Location of areas where large earthquake are most likely to occur . 57 Syntheses of seismicity, tectonic, and such data ....... 57 Stress level ....................... 57 Earthquake precursors .................... 58 General studies ..................... 58 Seismological studies ................... 60 Ground deformation, tilt, strain studies ........... 65 Gravity studies ..................... 75 Magnetic studies ..................... 77 Electrical studies .................... 78 Geochemical studies ................... 79 Water-level studies .................... 82 Animal behavioral studies ................. 84 Data processing ....................... 85 Numerical Modeling ..................... 87 Induced Seismicity Studies ..................... 88 Studies in Common Support of Hazards, Prediction and Induced Seismicity 91 Seismicity and seismic networks ................ 91 Physical basis of earthquakes ................. 107 Physical properties of the crust and upper mantle ....... 107 Laboratory studies .................... 112 Source mechanics .................... 117 Global Seismology Studies ..................... 119 Research .......................... 119 Seismograph station operation and design ............ 120 Data acquisition and dissemination ............... 122 Index of Principal Investigators ..................... 125 ILLUSTRATIONS Figure 1. Location of completed and current segment fault and geologic maps of the San Andreas fault zone in Los Angeles County . 11 2. Map showing the distribution and tectonic setting of carbon dioxide rich springs and gas wells in the conterminous U.S. and adjacent parts of Canada .................. 15 3. Location map of southern part of Melones fault ....... 18 4. Location map of study area along Garlock fault ....... 19 5. Location map of study areas in southern California ...... 22 6. Major structural features within the Reno quadrangle ..... 23 7. Location map of study areas in southeastern Alaska ...... 27 8. Photograph of Bootlegger Cove formation .......... 29 9. Location map of Quaternary faults and measuring sites for tectonic tilt in the Ogden-Salt Lake City, Utah area .... 30 10. Regional location map of study sites along the Wasatch fault . 40 11. Photograph of Hebgen fault scarp, Montana ......... 42 12. Location map of proposed monitoring sites .......... 64 13. Location map of strainmeter sites along Gulf of Alaska coastline between Katalla and Icy Bay .......... 67 14. Schematic drawing of Dalton Observatory .......... 70 15. Plan of precise level line and dry tilt arrays at Pinon Flat, California .................. 74 16. Radon and helium monitoring sites in southern California ... 80 17. Location map of groundwater radon sampling stations ..... 83 18. Location map of northeastern U.S. seismic network stations . 99 19. Seismic networks in northern Pakistan ........... 102 20. University of Utah seismic network ............. 103 21. Los Angeles Basin seismic network ............. 106 TABLES Table 1. Funding for the major elements of the USGS Earthquake Hazards Reduction Program, 1978 to 1981 ....... 2 2. Percent of funds allocated to regional, national, and topical studies in Earthquake Hazards Program, FY 1980 .... 3 3. Earthquake Prediction Program allocation of funds, FY 1980 6 INTRODUCTION by John R. Filson This report describes activities of the U.S. Geological Survey under the National Earthquake Hazards Reduction Program for fiscal year 1979 and the first half of fiscal year 1980 (October 1, 1978 through March 31, 1980). The national program was authorized by the Earthquake Hazards Reduction Act of 1977. In this program the responsibilities of the Geological Survey are to: Conduct research on the nature of earthquakes, earthquake prediction, hazards evaluation and delineation, and induced seismicity. Evaluate, with the advice of the National Earthquake Prediction Council, earthquake predictions. Prepare national seismic risk maps. Provide data and information on earthquake occurrences and hazards. The USGS earthquake hazards program is divided into four major elements. These elements and a brief description of the goals of each are: Earthquake Hazard and Risk Assessment - to identify the earthquake hazard potential on a national and regional basis and to evaluate the risk due to this hazard. Earthquake Prediction - to forecast the time, place, and magnitude of damaging earthquakes. Global Seismology - to conduct fundamental studies of seismological phenomena and to provide a sound data base for studies in observational seismology and public earthquake information services. Induced Seismicity - to prevent or mitigate the effects of earthquakes induced by the activities of man. Funding for these elements is summarized in table 1. We hope this report allows the reader to assess our accomplishments to date, the current status of our research efforts, and the directions we have taken to attain our goals. TABLE 1. Funding for the major elements of the USGS Earthquake Program, 1978 to 1981 Program element 1978 1979 1980 1981 (thousands of dollars) Earthquake prediction 15,575 15,764 15,190 15,610 Earthquake hazards and 10,422 10,885 11,001 11,277 risk assessment Global seismology and 2,558 2,884 3,532 3,656 earthquake information Induced seismic ity 1,179 1,199 1,202 1,288 Disaster warning 100 100 103 102 Totals 29,734 30,832 30,128 31,933 HIGHLIGHTS OF MAJOR ACCOMPLISHMENTS OCTOBER 1, 1978 to MARCH 31, 1980 (FY 1979-1980) EARTHQUAKE HAZARDS by Robert D. Brown, Jr. The earthquake hazards program consists of over 100 projects carried out by universities, private companies, state geological surveys and the USGS. The projects are classified as national, regional, or topical, according to the focus of the effort (table 2). National hazards studies are directed toward obtaining a reliable probabilistic assessment of earthquake hazard and risk for the nation. Regional studies are concerned with the delineation and assessment of earthquake-related geologic hazards within urban regions subject to high seismic risk. Earthquake hazards to be assessed include ground shaking, liquefaction, landsliding, coastal uplift and subsidence, surface faulting and water waves. As the first step in earthquake hazards assessment, topical studies seek to improve the physical basis for predicting the nature and likelihood of earthquake-related geologic hazards, particularly ground shaking, liquefaction and landsliding; to develop more reliable techniques and procedures for assessing earthquake potential of geologic structures or a geological province; and to develop more refined methods for estimating earthquake losses. TABLE 2. Percent of funds allocated to regional, national, and topical studies in Earthquake Hazards Program, FY 1960 Regional Studies 50 California 20 Western U.S. (excluding CA) IB Eastern U.S. 12 National Studies 15 Topical Studies 35 Earthquake potential 13 Ground motion 12 Ground failure 7 Risk 2 Post earthquake studies 1 100* Accomplishments in FY 1979 and the first half of FY 1980 are summarized below. National Studies Developed computer programs that estimate the probability of different levels of ground motion and accommodate the variability in attenuation, maximum earthquake magnitude, and fault length. Completed the planning and feasibility study for a national earthquake catalog, and began to assemble and analyze data for the catalog. From numerous seismic networks gathered data on earthquake activity in the Pacific Coast States (including Alaska), the Intermountain seismic belt (Utah, Montana, Idaho), the Mississippi Valley, the northeastern United States, and the southeastern United States. Regional Studies California Continued geologic research on known or suspected active fault, to establish recurrence rates and degree of hazard. Expanded geologic and geographical studies to evaluate crustal deformation and its relation to such geologic processes as faulting, folding, and regional warping or uplift. Continued mapping of Quaternary deposits in southern California, and measurements of the wave velocities in both northern
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