DOCSLIB.ORG

Campbell-Bozorgnia NGA Report

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Campbell-Bozorgnia NGA Report PACIFIC EARTHQUAKE ENGINEERING RESEARCH CENTER Campbell-Bozorgnia NGA Ground Motion Relations for the Geometric Mean Horizontal Component of Peak and Spectral Ground Motion Parameters Kenneth W. Campbell EQECAT, Inc. Beaverton, Oregon and Yousef Bozorgnia Pacific Earthquake Engineering Research Center University of California, Berkeley PEER 2007/02 MAY 2007 Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. PEER 2007/02 4. Title and Subtitle 5. Report Date Campbell-Bozorgnia NGA Ground Motion Relations for the May 2007 Geometric Mean Horizontal Component of Peak and Spectral Ground 6. Performing Organization Code Motion Parameters. 7. Author(s) 8. Performing Organization Report No. Kenneth W. Campbell and Yousef Bozorgnia UCB/PEER 2007/02 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Pacific Earthquake Engineering Research Center 325 Davis Hall MC 1792 University of California 11. Contract or Grant No. Berkeley, CA 94720 65A0058 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered California Department of Transportation Technical report through June 2006 Engineering Service Center 1801 30th St., West Building MS-9 14. Sponsoring Agency Code Sacramento, CA 95807 06681 15. Supplementary Notes This study was sponsored by the Pacific Earthquake Engineering Research Center’s Program of Applied Earthquake Engineering Research of Lifelines Systems supported by the California Department of Transportation, the California Energy Commission, and the Pacific Gas and Electric Company. 16. Abstract We present a new empirical ground motion model, commonly referred to as an attenuation relationship, which we developed as part of the PEER Next Generation Attenuation of Ground Motion (NGA) Project. Using a common database of worldwide strong motion recordings, we selected a subset of ground motion data and predictor variables that we believed were appropriate for use in developing our model. Consistent with the requirements of the PEER NGA Project, we developed both a median and aleatory uncertainty model for peak ground acceleration (PGA), peak ground velocity (PGV), peak ground displacement (PGD), and response spectral acceleration (PSA) and displacement (SD) for oscillator periods ranging from 0.01–10.0 s, magnitudes ranging from 4.0–8.0, and distances ranging from 0–200 km. We consider these models to be valid for use in the western United States and in other similar tectonically active regions of shallow crustal faulting worldwide. A comparison of our NGA model with our previous ground motion models (Campbell, 1997; Campbell and Bozorgnia, 1994, 2003) showed that the biggest differences in these models occur for sites located at small-to-moderate distances from large-magnitude earthquakes or near reverse faults with surface rupture, where the NGA model predicts lower ground motion, and for sites located on the hanging wall of dipping strike- slip and normal faults, where the NGA model predicts higher ground motion. We also found that the standard deviation is no longer a direct function of magnitude, which increases aleatory uncertainty for large-magnitude earthquakes and decreases it for small-magnitude earthquakes for stiff sites, compared to our previous models. However, the dependence of the standard deviation on nonlinear site effects in our new model can lead to less aleatory uncertainty for soft sites even at large magnitudes as compared to our previous models. 17. Key Words 18. Distribution Statement NGA, ground motion, Unlimited attenuation, near source, response spectra, site amplification, hanging wall, basin response 19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price Unclassified Unclassified 246 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized Campbell-Bozorgnia NGA Ground Motion Relations for the Geometric Mean Horizontal Component of Peak and Spectral Ground Motion Parameters Kenneth W. Campbell EQECAT, Inc. Beaverton, Oregon and Yousef Bozorgnia Pacific Earthquake Engineering Research Center University of California, Berkeley PEER Report 2007/02 Pacific Earthquake Engineering Research Center College of Engineering University of California, Berkeley May 2007 ABSTRACT We present a new empirical ground motion model, commonly referred to as an attenuation relationship, which we developed as part of the PEER Next Generation Attenuation of Ground Motion (NGA) Project. Using a common database of worldwide strong motion recordings, we selected a subset of ground motion data and predictor variables that we believed were appropriate for use in developing our model. Consistent with the requirements of the PEER NGA Project, we developed both a median and aleatory uncertainty model for peak ground acceleration (PGA), peak ground velocity (PGV), peak ground displacement (PGD), and response spectral acceleration (PSA) and displacement (SD) for oscillator periods ranging from 0.01–10.0 s, magnitudes ranging from 4.0–8.0, and distances ranging from 0–200 km. We consider these models to be valid for use in the western United States and in other similar tectonically active regions of shallow crustal faulting worldwide. A comparison of our NGA model with our previous ground motion models (Campbell, 1997, 2000, 2001; Campbell and Bozorgnia, 1994, 2003a, 2003b, 2003c, 2004) showed that the biggest differences in these models occur for sites located at small-to-moderate distances from large-magnitude earthquakes or near reverse faults with surface rupture, where the NGA model predicts lower ground motion, and for sites located on the hanging wall of dipping strike-slip and normal faults, where the NGA model predicts higher ground motion. We also found that the standard deviation is no longer a direct function of magnitude, which increases aleatory uncertainty for large-magnitude earthquakes and decreases it for small-magnitude earthquakes for stiff sites, compared to our previous models. However, the dependence of the standard deviation on nonlinear site effects in our new model can lead to less aleatory uncertainty for soft sites even at large magnitudes as compared to our previous models. iii ACKNOWLEDGMENTS This study was sponsored by the Pacific Earthquake Engineering Research Center’s Program of Applied Earthquake Engineering Research of Lifelines Systems supported by the California Department of Transportation, the California Energy Commission, and the Pacific Gas and Electric Company. This work made use of the Earthquake Engineering Research Centers Shared Facilities supported by the National Science Foundation, under award number EEC-9701568 through the Pacific Earthquake Engineering Research (PEER) Center. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect those of the National Science Foundation. We would like to thank all of the NGA model developers and supporting researchers for their assistance and lively discussions throughout the project. We would especially like to thank Norm Abrahamson, Dave Boore, Brian Chiou, Ed Idriss, Walt Silva, and Bob Youngs for their many constructive comments during the many interaction meetings that were held throughout the project; and Maury Power, Tom Shantz, and Cliff Roblee for their dedicated efforts in managing the project. We would also like to thank Steve Day, Walt Silva, Paul Somerville, and Paul Spudich for providing us with ground motion simulation and analysis results that assisted us in developing our model. iv CONTENTS ABSTRACT.................................................................................................................................. iii ACKNOWLEDGMENTS ........................................................................................................... iv TABLE OF CONTENTS ..............................................................................................................v LIST OF FIGURES ..................................................................................................................... ix LIST OF TABLES ....................................................................................................................... xi 1 INTRODUCTION.. ...............................................................................................................1 1.1 Scope of the PEER NGA Project....................................................................................1 1.2 Objectives of the PEER NGA Project.............................................................................2 2 STRONG MOTION DATABASE.......................................................................................5 3 GROUND MOTION MODEL.............................................................................................9 3.1 Empirical Ground Motion Model .................................................................................10 3.1.1 Strong Motion Parameter ..................................................................................10 3.1.2 Median Ground Motion Model.........................................................................11 3.1.3 Aleatory Uncertainty Model .............................................................................13 3.1.4 Regression Results............................................................................................17 3.2 Justification of Functional Forms .................................................................................18
Load more

Recommended publications
  • The Commercial Property Owner's Guide to Earthquake Safety
    Commercial Property Owner’s Guide to Earthquake Safety 2006 Edition Published by the California Seismic Safety Commission State of California Arnold Schwarzenegger, Governor SSC No. 06-02 This 2006 Edition of the Commercial Property Owner’s Guide to Earthquake Safety replaces the 1998 Edition on October 1, 2006. Publishing Information The Commercial Property Owner’s Guide to Earthquake Safety was developed and published by the California Seismic Safety Commission. It was distributed under the provisions of the Library Distribution Act and Government Code Section 11096. Copyrighted 2006 by the California Seismic Safety Commission All rights reserved Legislation This guide has been developed and adopted by the California Seismic Safety Commission as required by the Business and Professions Code Section 10147. Ordering Information Copies of this booklet are available from the California Seismic Safety Commission, 1755 Creekside Oaks Drive, Suite 100, Sacramento, CA 95833. To order call (916) 263-5506 or download via our website at http://www.seismic.ca.gov/sscpub.htm On the Cover: The roof of this department store was not well connected to its walls and partially collapsed in Yucca Valley during the 1992 Landers Earthquake. ii The Commercial Property Owner’s Guide to Earthquake Safety CONTENTS Page Page INTRODUCTION ..................................................1 OTHER EARTHQUAKE-RELATED Your Commercial Property and the Law ..............2 CONCERNS ........................................... 26 Recommendations ...............................................3
    [Show full text]
  • New Empirical Relationships Among Magnitude, Rupture Length, Rupture Width, Rupture Area, and Surface Displacement
    Bulletin of the Seismological Society of America, Vol. 84, No. 4, pp. 974-1002, August 1994 New Empirical Relationships among Magnitude, Rupture Length, Rupture Width, Rupture Area, and Surface Displacement by Donald L. Wells and Kevin J. Coppersmith Abstract Source parameters for historical earthquakes worldwide are com­ piled to develop a series of empirical relationships among moment magnitude (M), surface rupture length, subsurface rupture length, downdip rupture width, rupture area, and maximum and average displacement per event. The resulting data base is a significant update of previous compilations and includes the ad­ ditional source parameters of seismic moment, moment magnitude, subsurface rupture length, downdip rupture width, and average surface displacement. Each source parameter is classified as reliable or unreliable, based on our evaluation of the accuracy of individual values. Only the reliable source parameters are used in the final analyses. In comparing source parameters, we note the fol­ lowing trends: (1) Generally, the length of rupture at the surface is equal to 75% of the subsurface rupture length; however, the ratio of surface rupture length to subsurface rupture length increases with magnitude; (2) the average surface dis­ placement per event is about one-half the maximum surface displacement per event; and (3) the average subsurface displacement on the fault plane is less than the maximum surface displacement but more than the average surface dis­ placement. Thus, for most earthquakes in this data base, slip on the fault plane at seismogenic depths is manifested by similar displacements at the surface. Log-linear regressions between earthquake magnitude and surface rupture length, subsurface rupture length, and rupture area are especially well correlated, show­ ing standard deviations of 0.25 to 0.35 magnitude units.
    [Show full text]
  • Changes in Geyser Eruption Behavior and Remotely Triggered Seismicity in Yellowstone National Park Produced by the 2002 M 7.9 Denali Fault Earthquake, Alaska
    Changes in geyser eruption behavior and remotely triggered seismicity in Yellowstone National Park produced by the 2002 M 7.9 Denali fault earthquake, Alaska S. Husen* Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah 84112, USA R. Taylor National Park Service, Yellowstone Center for Resources, Yellowstone National Park, Wyoming 82190, USA R.B. Smith Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah 84112, USA H. Healser National Park Service, Yellowstone Center for Resources, Yellowstone National Park, Wyoming 82190, USA ABSTRACT STUDY AREA Following the 2002 M 7.9 Denali fault earthquake, clear changes in geyser activity and The Yellowstone volcanic field, Wyoming, a series of local earthquake swarms were observed in the Yellowstone National Park area, centered in Yellowstone National Park (here- despite the large distance of 3100 km from the epicenter. Several geysers altered their after called ‘‘Yellowstone’’), is one of the larg- eruption frequency within hours after the arrival of large-amplitude surface waves from est silicic volcanic systems in the world the Denali fault earthquake. In addition, earthquake swarms occurred close to major (Christiansen, 2001; Smith and Siegel, 2000). geyser basins. These swarms were unusual compared to past seismicity in that they oc- Three major caldera-forming eruptions oc- curred simultaneously at different geyser basins. We interpret these observations as being curred within the past 2 m.y., the most recent induced by dynamic stresses associated with the arrival of large-amplitude surface waves. 0.6 m.y. ago. The current Yellowstone caldera We suggest that in a hydrothermal system dynamic stresses can locally alter permeability spans 75 km by 45 km (Fig.
    [Show full text]
  • The Race to Seismic Safety Protecting California’S Transportation System
    THE RACE TO SEISMIC SAFETY PROTECTING CALIFORNIA’S TRANSPORTATION SYSTEM Submitted to the Director, California Department of Transportation by the Caltrans Seismic Advisory Board Joseph Penzien, Chairman December 2003 The Board of Inquiry has identified three essential challenges that must be addressed by the citizens of California, if they expect a future adequately safe from earthquakes: 1. Ensure that earthquake risks posed by new construction are acceptable. 2. Identify and correct unacceptable seismic safety conditions in existing structures. 3. Develop and implement actions that foster the rapid, effective, and economic response to and recovery from damaging earthquakes. Competing Against Time Governor’s Board of Inquiry on the 1989 Loma Prieta Earthquake It is the policy of the State of California that seismic safety shall be given priority consideration in the allo- cation of resources for transportation construction projects, and in the design and construction of all state structures, including transportation structures and public buildings. Governor George Deukmejian Executive Order D-86-90, June 2, 1990 The safety of every Californian, as well as the economy of our state, dictates that our highway system be seismically sound. That is why I have assigned top priority to seismic retrofit projects ahead of all other highway spending. Governor Pete Wilson Remarks on opening of the repaired Santa Monica Freeway damaged in the 1994 Northridge earthquake, April 11, 1994 The Seismic Advisory Board believes that the issues of seismic safety and performance of the state’s bridges require Legislative direction that is not subject to administrative change. The risk is not in doubt. Engineering, common sense, and knowledge from prior earthquakes tells us that the consequences of the 1989 and 1994 earthquakes, as devastating as they were, were small when compared to what is likely when a large earthquake strikes directly under an urban area, not at its periphery.
    [Show full text]
  • Lessons Learned from Oil Pipeline Natech Accidents and Recommendations for Natech Scenario Development
    Lessons learned from oil pipeline natech accidents and recommendations for natech scenario development Final Report Serkan Girgin, Elisabeth Krausmann 2015 Report EUR 26913 EN European Commission Joint Research Centre Institute for the Protection and Security of the Citizen Contact information Elisabeth Krausmann Address: Joint Research Centre, Via E. Fermi 2749, 21027 Ispra (VA), Italy E-mail: [email protected] https://ec.europa.eu/jrc Legal Notice This publication is a Science and Policy Report by the Joint Research Centre, the European Commission’s in-house science service. It aims to provide evidence-based scientific support to the European policy-making process. The scientific output expressed does not imply a policy position of the European Commission. Neither the European Commission nor any person acting on behalf of the Commission is responsible for the use which might be made of this publication. Image credits: Trans-Alaska Pipeline on slider supports at the Denali Fault crossing: ©T Dawson, USGS JRC92700 EUR 26913 EN ISBN 978-92-79-43970-4 ISSN 1831-9424 doi:10.2788/20737 Luxembourg: Publications Office of the European Union, 2015 © European Union, 2015 Reproduction is authorised provided the source is acknowledged. Abstract Natural hazards can impact oil transmission pipelines with potentially adverse consequences on the population and the environment. They can also cause significant economic impacts to pipeline operators. Currently, there is only limited historical information available on the dynamics of natural hazard impact on pipelines and Action A6 of the EPCIP 2012 Programme aimed at shedding light on this issue. This report presents the findings of the second year of the study that focused on the analysis of onshore hazardous liquid transmission pipeline natechs, with special emphasis on natural hazard impact and damage modes, incident consequences, and lessons learned for scenario building.
    [Show full text]
  • UCLA UCLA Electronic Theses and Dissertations
    UCLA UCLA Electronic Theses and Dissertations Title An Improved Framework for the Analysis and Dissemination of Seismic Site Characterization Data at Varying Resolutions Permalink https://escholarship.org/uc/item/6p35w167 Author Ahdi, Sean Kamran Publication Date 2018 Supplemental Material https://escholarship.org/uc/item/6p35w167#supplemental Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA Los Angeles An Improved Framework for the Analysis and Dissemination of Seismic Site Characterization Data at Varying Resolutions A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Civil Engineering by Sean Kamran Ahdi 2018 © Copyright by Sean Kamran Ahdi 2018 ABSTRACT OF THE DISSERTATION An Improved Framework for the Analysis and Dissemination of Seismic Site Characterization Data at Varying Resolutions by Sean Kamran Ahdi Doctor of Philosophy in Civil Engineering University of California, Los Angeles, 2018 Professor Jonathan Paul Stewart, Chair The most commonly used parameter for representing site conditions for ground motion studies is the time-averaged shear-wave velocity in the upper 30 m, or VS30. While it is preferred to compute VS30 from a directly measured shear-wave velocity (VS) profile using in situ geophysical methods, this information is not always available. One major application of VS30 is the development of ergodic site amplification models, for example as part of ground motion model (GMM) development projects, which require VS30 values for all sites. The first part of this dissertation (Chapters 2-4) addresses the development of proxy-based models for estimation of VS30 for application in subduction zone regions.
    [Show full text]
  • Engineering Geology and Seismology for Public Schools and Hospitals in California
    The Resources Agency California Geological Survey Michael Chrisman, Secretary for Resources Dr. John G. Parrish, State Geologist Engineering Geology and Seismology for Public Schools and Hospitals in California to accompany California Geological Survey Note 48 Checklist by Robert H. Sydnor, Senior Engineering Geologist California Geological Survey www.conservation.ca.gov/cgs July 1, 2005 316 pages Engineering Geology and Seismology performance–based analysis, diligent subsurface for Public Schools and Hospitals sampling, careful reading of the extensive geologic in California literature, thorough knowledge of the California Building Code, combined with competent professional geological work. by Robert H. Sydnor Engineering geology aspects of hospital and public California Geological Survey school sites include: regional geology, regional fault July 1, 2005 316 pages maps, site-specific geologic mapping, geologic cross- sections, active faulting, official zones of investigation Abstract for liquefaction and landslides, geotechnical laboratory The 446+ hospitals, 1,400+ skilled nursing facilities testing of samples, expansive soils, soluble sulfate ±9,221 public schools, and 109 community college evaluation for Type II or V Portland-cement selection, campuses in California are regulated under California and flooding. Code of Regulations, Title 24, California Building Code. Seismology aspects include: evaluation of historic These facilities are plan–checked by senior–level seismicity, probabilistic seismic hazard analysis of Registered Structural Engineers within the Office of earthquake ground–motion, use of proper code terms Statewide Health Planning and Development (OSHPD) (Upper–Bound Earthquake ground–motion and Design– for hospitals and skilled nursing facilities, and the Basis ground–motion), classification of the geologic Division of the State Architect (DSA) for public schools, subgrade by shear–wave velocity to select the correct community colleges, and essential services buildings.
    [Show full text]
  • Geologic Mapping and the Trans-Alaska Pipeline Using Geologic Maps to Protect Infrastructure and the Environment
    Case Study Geologic Mapping and the Trans-Alaska Pipeline Using geologic maps to protect infrastructure and the environment Overview The 800-mile-long Trans-Alaska Pipeline, which starts at examining the fault closely and analyzing its rate of Prudhoe Bay on Alaska’s North Slope, can carry 2 million movement, geologists determined that the area around barrels of oil per day south to the port of Valdez for export, the pipeline crossing—had the potential to generate a equal to roughly 10% of the daily consumption in the United very significant earthquake greater than magnitude 8. States in 2017. The pipeline crosses the Denali fault some 90 miles south of Fairbanks. A major earthquake along the fault could cause the pipeline to rupture, spilling crude oil into the surrounding environment. Denali Fault Trace In 2002, a magnitude 7.9 earthquake struck the Denali fault, one of the largest earthquakes ever recorded in North America, which caused violent shaking and large ground movement where the pipeline crossed the fault. However, the pipeline did not spill a drop of oil, and only saw a 3-day shutdown for inspections. Geologic mapping of the pipeline area prior to its construction allowed geologists and engineers to identify and plan for earthquake hazards in the pipeline design, which mitigated damage to pipeline infrastructure and helped prevent a potentially major oil spill during the 2002 earthquake. Geologic Mapping The Trans-Alaska Pipeline after the 2002 earthquake on the Denali Mapping the bedrock geology along the 1,000-mile-long fault. The fault rupture occurred between the second and third Denali fault revealed information on past movement on the beams fault and the likely direction of motion on the fault in future Image credit: Tim Dawson, U.S.
    [Show full text]
  • Liquefaction Limits in Earthquake And
    Floods on Mars Released from Groundwater by Impact Chi-yuen Wang, Michael Manga and Alex Wong Department of Earth and Planetary Science University of California, Berkeley CA 94720 On earth, large earthquakes commonly cause saturated soils to liquefy and streamflow to increase. We suggest that meteoritic impacts on Mars may have repeatedly caused similar liquefaction to enable violent eruption of groundwater. The amount of erupted water may be comparable to that required to produce catastrophic floods and to form outflow channels. Key words: liquefaction, impacts, chaos 1. Introduction Liquefaction frequently occurs on Earth during or immediately after large earthquakes, when saturated soils lose their shear resistance, become fluid-like, and are ejected to the surface, causing lateral spreading of ground and foundering of engineered foundations (e.g., Terzaghi et al., 1996). During the 1964 Alaskan earthquake, for example, ejection of fluidized sediments occurred at distances more than 400 km from the epicenter (Waller, 1968). Increased streamflow is also commonly observed after earthquakes (Montgomery and Manga, 2003). Suggested causes include coseismic liquefaction (Manga et al., 2003), coseismic strain (Muir-Wood and King, 1993), enhanced permeability (Rojstaczer et al., 1995) and rupturing of hydrothermal reservoirs (Wang et al., 2004a). Extensive laboratory and field studies (e.g., Terzaghi et al., 1996) show that saturated soils liquefy during ground shaking as a result of pore-pressure buildup that in turn is due to the compaction of soils in an undrained condition. Furthermore, laboratory experiments (Dobry, 1985; Vucetic, 1994) showed that the threshold of pore-pressure buildup is insensitive to the type of soils (from clays to loose sand) and the environmental conditions.
    [Show full text]
  • The Race to Seismic Safety Protecting California’S Transportation System
    THE RACE TO SEISMIC SAFETY PROTECTING CALIFORNIA’S TRANSPORTATION SYSTEM Submitted to the Director, California Department of Transportation by the Caltrans Seismic Advisory Board Joseph Penzien, Chairman December 2003 The Board of Inquiry has identified three essential challenges that must be addressed by the citizens of California, if they expect a future adequately safe from earthquakes: 1. Ensure that earthquake risks posed by new construction are acceptable. 2. Identify and correct unacceptable seismic safety conditions in existing structures. 3. Develop and implement actions that foster the rapid, effective, and economic response to and recovery from damaging earthquakes. Competing Against Time Governor’s Board of Inquiry on the 1989 Loma Prieta Earthquake It is the policy of the State of California that seismic safety shall be given priority consideration in the allo- cation of resources for transportation construction projects, and in the design and construction of all state structures, including transportation structures and public buildings. Governor George Deukmejian Executive Order D-86-90, June 2, 1990 The safety of every Californian, as well as the economy of our state, dictates that our highway system be seismically sound. That is why I have assigned top priority to seismic retrofit projects ahead of all other highway spending. Governor Pete Wilson Remarks on opening of the repaired Santa Monica Freeway damaged in the 1994 Northridge earthquake, April 11, 1994 The Seismic Advisory Board believes that the issues of seismic safety and performance of the state’s bridges require Legislative direction that is not subject to administrative change. The risk is not in doubt. Engineering, common sense, and knowledge from prior earthquakes tells us that the consequences of the 1989 and 1994 earthquakes, as devastating as they were, were small when compared to what is likely when a large earthquake strikes directly under an urban area, not at its periphery.
    [Show full text]
  • A PALEOSEISMIC STUDY ALONG the CENTRAL DENALI FAULT, CHISTOCHINA GLACIER AREA, SOUTH-CENTRAL ALASKA by R.D
    Division of Geological & Geophysical Surveys REPORT OF INVESTIGATION 2011-1 A PALEOSEISMIC STUDY ALONG THE CENTRAL DENALI FAULT, CHISTOCHINA GLACIER AREA, SOUTH-CENTRAL ALASKA by R.D. Koehler, S.F. Personius, D.P. Schwarz, P.J. Haeussler, and G.G. Seitz Photograph of surface rupture scarps related to the 2002 Denali fault earthquake near Chistochina Glacier, Alaska. Scarps are shadowed and extend across the center of the photo. March 2011 Released by STATE OF ALASKA DEPARTMENT OF NATURAL RESOURCES Division of Geological & Geophysical Surveys 3354 College Rd. Fairbanks, Alaska 99709-3707 $2.00 STATE OF ALASKA Sean Parnell, Governor DEPARTMENT OF NATURAL RESOURCES Daniel S. Sullivan, Commissioner DIVISION OF GEOLOGICAL & GEOPHYSICAL SURVEYS Robert F. Swenson, State Geologist and Director Publications produced by the Division of Geological & Geophysical Surveys can be examined at the following locations. To order publications, contact the Fairbanks office. Alaska Division of Geological & Geophysical Surveys 3354 College Rd., Fairbanks, Alaska 99709-3707 Phone: (907) 451-5020 Fax (907) 451-5050 [email protected] www.dggs.alaska.gov Alaska State Library Alaska Resource Library & Information State Office Building, 8th Floor Services (ARLIS) 3354 College Road 3150 C Street, Suite 100 Juneau, Alaska 99811-0571 Anchorage, Alaska 99503 Elmer E. Rasmuson Library University of Alaska Anchorage Library University of Alaska Fairbanks 3211 Providence Drive Fairbanks, Alaska 99775-1005 Anchorage, Alaska 99508 This publication released by the Division
    [Show full text]
  • A Mechanism for Sustained Groundwater Pressure Changes Induced by Distant Earthquakes Emily E
    JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 108, NO. B8, 2390, doi:10.1029/2002JB002321, 2003 A mechanism for sustained groundwater pressure changes induced by distant earthquakes Emily E. Brodsky,1 Evelyn Roeloffs,2 Douglas Woodcock,3 Ivan Gall,4 and Michael Manga5 Received 25 November 2002; revised 8 March 2003; accepted 3 April 2003; published 22 August 2003. [1] Large, sustained well water level changes (>10 cm) in response to distant (more than hundreds of kilometers) earthquakes have proven enigmatic for over 30 years. Here we use high sampling rates at a well near Grants Pass, Oregon, to perform the first simultaneous analysis of both the dynamic response of water level and sustained changes, or steps. We observe a factor of 40 increase in the ratio of water level amplitude to seismic wave ground velocity during a sudden coseismic step. On the basis of this observation we propose a new model for coseismic pore pressure steps in which a temporary barrier deposited by groundwater flow is entrained and removed by the more rapid flow induced by the seismic waves. In hydrothermal areas, this mechanism could lead to 4 Â 10À2 MPa pressure changes and triggered seismicity. INDEX TERMS: 1829 Hydrology: Groundwater hydrology; 7209 Seismology: Earthquake dynamics and mechanics; 7212 Seismology: Earthquake ground motions and engineering; 7260 Seismology: Theory and modeling; 7294 Seismology: Instruments and techniques; KEYWORDS: earthquakes, triggering, time-dependent hydrology, fractures Citation: Brodsky, E. E., E. Roeloffs, D. Woodcock, I. Gall, and M. Manga, A mechanism for sustained groundwater pressure changes induced by distant earthquakes, J. Geophys. Res., 108(B8), 2390, doi:10.1029/2002JB002321, 2003.
    [Show full text]