DOCSLIB.ORG

Extreme Ground Motions and Yucca Mountain

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Extreme Ground Motions and Yucca Mountain Extreme Ground Motions and Yucca Mountain Open-File Report 2013–1245 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2013 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit http://www.usgs.gov or call 1–888–ASK–USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Suggested citation: Hanks, T.C., Abrahamson, N.A., Baker, J.W., Boore, D.M., Board, M., Brune, J.N., Cornell, C.A., Whitney, J.W, 2013, Extreme ground motions and Yucca Mountain: U.S. Geological Survey Open-File Report 2013–1245, 105 p., http://dx.doi.org/10.3133/ofr20131245. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. ISSN 2331-1258 Cover. Yucca mountain crest with a dusting of snow, looking north. Photo from the Department of Energy, Office of Civilian Radioactive Waste Management. Contents Introduction ................................................................................................................................................................. 1 Extreme Ground Motions and PSHA .......................................................................................................................... 7 Geologic and Tectonic Setting of Yucca Mountain ..................................................................................................... 9 The “Million-Year-Old Landscape” ............................................................................................................................ 16 The Many Dimensions of Extreme Ground Motions ................................................................................................. 20 Physical Limits to Earthquake Ground Motion .......................................................................................................... 25 Unexceeded Ground Motion ..................................................................................................................................... 30 Lithophysal Units ................................................................................................................................................... 30 Precariously Balanced Rocks (PBRs) ................................................................................................................... 33 Event Frequencies .................................................................................................................................................... 39 Exceptionally Large PGAs and PGVs ................................................................................................................... 41 Normal-Faulting Surface Displacements ............................................................................................................... 44 mb-M Stress Drops for Continental Crustal Earthquakes ...................................................................................... 45 Magnitude-Dependent Apparent Stress? .............................................................................................................. 48 Points in Hazard Space ............................................................................................................................................ 50 Simplified Hazard Models ..................................................................................................................................... 51 Physical Limits ...................................................................................................................................................... 53 Unexceeded Ground Motions ............................................................................................................................... 54 Lithophysal Fragilities ............................................................................................................................................ 58 PBR Fragilities ...................................................................................................................................................... 59 Fragile Geologic Structures that Evolve with Time ................................................................................................ 63 Discussion and Implications...................................................................................................................................... 67 The End…of the Beginning ....................................................................................................................................... 70 Acknowledgments ..................................................................................................................................................... 72 References ............................................................................................................................................................... 73 Appendix I. Data for Exposure-Age and Erosion-Rate Determinations ..................................................................... 79 10Be Analytical Methods, Data-Reduction, and Exposure Age Calculations ......................................................... 82 36Cl Analytical Methods and Data Reduction ........................................................................................................ 83 36Cl Exposure Age Calculations ............................................................................................................................ 84 References ............................................................................................................................................................ 84 Appendix II. Erosion-Rate Estimates from Detritus Volumes on the West Face of Yucca Mountain......................... 86 Appendix III. Fragility Data and Calculations for the Lithophysal Units ..................................................................... 90 1.0 Introduction ................................................................................................................................................ 90 2.0 Geology of the YMP Repository Host Rock Mass ...................................................................................... 90 2.1 Topopah Spring Formation ...................................................................................................................... 90 2.2 Nonlithophysal Subunits of the Topopah Spring Formation ..................................................................... 91 2.3 Lithophysal Subunits of the Topopah Spring Formation ........................................................................... 92 3.0 Use of Lithophysae and Tptpll Fracture Fabric as a Marker for Extreme Ground Motion ........................... 93 3.1 Introduction .............................................................................................................................................. 93 3.2 Approach to Establishing Unexceeded Shear-Strains .............................................................................. 94 3.3 Analysis of Expected Failure Observations if Threshold Shear Strains are Exceeded ............................. 98 4.0 Development of a Bounded Horizontal PGV Hazard Curve for the Yucca Mt. Site .................................. 100 4.1 Site Response Modeling and Development of Bounded PGV Distributions ........................................... 100 4.2 Development of a Bounded Horizontal PGV Hazard Curve for Yucca Mountain ................................... 103 References .......................................................................................................................................................... 105 iii Figures 1. Google Earth image overlain on a digital elevation map, color-coded according to elevation, looking northeast over Bare Mountain and Crater Flat to Yucca Mountain and beyond, southwestern Nevada ........ 2 2. Aerial photo looking southeast across the steep west face of Yucca Mountain, the ~10-million-year-old scarp of the Solitario Canyon Fault at its base............................................................................................... 3 3. Plot showing probability-of-exceedance calculations for horizontal peak ground acceleration at Point A, a hypothetical, reference rock-outcrop site at the repository horizon ............................................................. 5 4. Plot showing probability-of-exceedance calculations for horizontal peak ground velocity at Point A, a hypothetical, reference rock-outcrop site at the repository horizon ................................................................ 6 5. Simplified geologic map showing principal faults, blocks, and volcanic centers from Yucca Mountain to Bare Mountain. ............................................................................................................................................ 11 6. Cross section showing interpretation of seismic profiling
Load more

Recommended publications
  • 95-289, "Origins of Secondary Silica with Yucca Mountain, Nye
    ORIGINS OF SECONDARY SILICA WITHIN YUCCA MOUNTAIN, NYE COUNTY, SOUTHWESTERN NEVADA by Richard J. Moscati and Joseph F. Whelan U.S. GEOLOGICAL SURVEY Open-File Report 95-289 Prepared in cooperation with the NEVADA OPERATIONS OFFICE, U.S. DEPARTMENT OF ENERGY, under Interagency Agreement DE-AI08-92NV1 0874 Denver, Colorado 1996 CONTENTS A b stract ................................................................................................................................................................................. ..........................................I Introduction ......................................... ,...............,......................................,.................................;...................................... ....... I A cknow ledgm ents ................................................................................................................................................................. ............................................I Geologic setting .............................................................................................................................. 3 Silica and calcite petrology ................................................................................................................................................... ..........................................3 Analytical methods ........................................................................................................................... 5 Discussion of origins of silica ..............................................................................................................................................
    [Show full text]
  • Weiss Et Al, 1995) This Paper Disputes the Interpretation of Castor Et Al
    EVALUATION OF THE GEOLOGIC RELATIONS AND SEISMOTECTONIC STABILITY OF THE YUCCA MOUNTAIN AREA NEVADA NUCLEAR WASTE SITE INVESTIGATION (NNWSI) PROGRESS REPORT 30 SEPTEMBER 1995 CENTER FOR NEOTECTONIC STUDIES MACKAY SCHOOL OF MINES UNIVERSITY OF NEVADA, RENO DISTRIBUTION OF ?H!S DOCUMENT IS UKLMTED DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document CONTENTS SECTION I. General Task Steven G. Wesnousky SECTION II. Task 1: Quaternary Tectonics John W. Bell Craig M. dePolo SECTION III. Task 3: Mineral Deposits Volcanic Geology Steven I. Weiss Donald C. Noble Lawrence T. Larson SECTION IV. Task 4: Seismology James N. Brune Abdolrasool Anooshehpoor SECTION V. Task 5: Tectonics Richard A. Schweickert Mary M. Lahren SECTION VI. Task 8: Basinal Studies Patricia H. Cashman James H. Trexler, Jr. DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsi- bility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Refer- ence herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recom- mendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.
    [Show full text]
  • Board of County Phone (775) 482-8191 Fax (775) 751-7093 Comnussioners
    Pahrump Office Tonopah Office Nye County Govermnent Center Nye County Courthouse 2100 F. Walt Williams Dove William P. Beko Justice Facility Suite 100 P0 Box 153 Palmimp, NV 89048 Tonopah, NV 89049 Phone (775) 751-7075 Board of County Phone (775) 482-8191 Fax (775) 751-7093 Comnussioners. Fax (775) 482-8198 Nye County, Nevada April 30, 2019 The Honorable John Barrasso The Honorable Thomas R. Carper Chairman, Committee on Environment and Ranking Member, Committee on Public Works Environment and Public Works 410 Dirksen Senate Office Building 456 Dirksen Senate Office Building United States Senate United States Senate Washington, DC 20510 Washington, DC 20510 Dear: Chairman Barrasso and Ranking Member Carper: On behalf of the Nye County Conmiission, along with eight other Nevada counties (out of a total of seventeen) I strongly urge you to support the Senate bill to jump start the licensing hearing for the Yucca Mountain Nuclear Waste Repository. This position is in accordance with the law, supports the objective scientific studies on the safety of the repository and has the support of local governments in Nevada. It is the right thing to do. As you know, funding for the license process has been denied for nine years on purely political grounds. The overwhelming body of scientific studies done on the proposed repository have demonstrated that it can be built and operated safely. This includes the safety reviews done by the professionals at the Nuclear Regulatory Commission (NRC). Further, the funding we are requesting will be used to conduct further scientific reviews by the NRC. The opponents of the repository will have every opportunity to show that the repository is unsafe, if they can make that case based on facts.
    [Show full text]
  • OR Get the Facts About YUCCA MOUNTAIN
    Where is Yucca Mountain? Yucca Mountain is the only site being Yucca Mountain is located in Nevada, about an considered by the Department of Energy hour northwest of Las Vegas. It is in the desert, (DOE) as a “permanent disposal” site for the and the land it occupies includes public land, United States’ highly radioactive nuclear Nevada Test Site land, and Nellis Air Force Base waste. This spent nuclear fuel and high-level land. However, all of this land is part of the waste is currently located at 77 sites across the For more information, contact: Western Shoshone traditional homelands. If a country and would have to be transported by dump is built at Yucca Mountain, the Shoshone truck or rail to Yucca Mountain if that site is will lose access to this sacred place. approved as a geologic repository. Public Citizen’s Critical Mass Energy Under current law, 70,000 metric tons and Environment Program of waste would be allowed to be stored at 215 Pennsylvania Avenue, SE Yucca Mountain, with 63,000 tons of that Washington, DC 20003 being commercial waste and the rest being www.citizen.org/cmep DOE waste. However, that still would not 202-546-4996 OREGON IDAHOIDAHO accommodate all the waste projected to be 202-547-7392 (fax) Get the Facts about Washoe produced in the U.S. (an estimated 107,500 County Humboldt metric tons of both commercial and DOE County YUCCA Elko County waste). OR Scientific study at Yucca Mountain has MOUNTAIN, Pershing revealed a host of potential problems at the RenoReno County Lander Nuclear Information County Eureka site.
    [Show full text]
  • The Initiation and Evolution of Ignimbrite Faults, Gran Canaria, Spain
    The initiation and evolution of ignimbrite faults, Gran Canaria, Spain Aisling Mary Soden B.A. (Hons.), Trinity College Dublin Thesis presented for the degree of Doctor of Philosophy (Ph.D.) University of Glasgow Department of Geographical & Earth Sciences January 2008 © Aisling M. Soden, 2008 Abstract Abstract Understanding how faults initiate and fault architecture evolves is central to predicting bulk fault zone properties such as fault zone permeability and mechanical strength. The study of faults at the Earth’s surface and at near-surface levels is significant for the development of high level nuclear waste repositories, and CO2 sequestration facilities. Additionally, with growing concern over water resources, understanding the impact faults have on contaminant transport between the unsaturated and saturated zone has become increasingly important. The proposal of a high-level nuclear waste repository in the tuffs of Yucca Mountain, Nevada has stimulated interest into research on the characterisation of brittle deformation in non-welded to densely welded tuffs and the nature of fluid flow in these faults and fractures. The majority of research on the initiation and development of faults has focussed on shear faults in overall compressional stress regimes. Dilational structures have been examined in compressional settings e.g. overlapping faults generating extensional oversteps, or in normal faults cutting mechanical layered stratigraphy. Previous work has shown the affect mechanical stratigraphy has on fault dip angle; competent layers have steeply dipping segments and less competent layers have shallowly dipping segments. Displacement is accommodated by shear failure of the shallow segments and hybrid failure of the steeply dipping segments. As the fault walls of the shear failure segment slip past each other the walls of the hybrid failure segment are displaced horizontally as well as vertically thus forming dilation structures such as pull-aparts or extensional bends.
    [Show full text]
  • Water-Resources Investigations Report 84-4267 Prepared In
    HYDROLOGY OF YUCCA MOUNTAIN AND VICINITY, NEVADA-CALIFORNIA- INVESTIGATIVE RESULTS THROUGH MID-1983 U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 84-4267 Prepared in cooperation with the U.S. DEPARTMENT OF ENERGY HYDROLOGY OF YUCCA MOUNTAIN AND VICINITY, NEVADA-CALIFORNIA- INVESTIGATIVE RESULTS THROUGH MID-1983 By R. K. Waddell, 0. H. Robison, and R. K. Blankennagel U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 84-4267 Prepared in cooperation with the U.S. DEPARTMENT OF ENERGY Denver, Colorado 1984 UNITED STATES DEPARTMENT OF THE INTERIOR WILLIAM P. CLARK, Secretary GEOLOGICAL SURVEY Dallas L. Peck, Director For additional information Copies of this report can write to: be purchased from: Chief, Nuclear Hydrology Program Open-File Services Section U.S. Geological Survey Western Distribution Branch Water Resources Division, U.S. Geological Survey Central Region Box 25425, Federal Center Box 25046, Mail Stop 416 Denver, CO 80225 Denver Federal Center Telephone: (303) 236-7476 Denver, CO 80225 CONTENTS Page Abstract. ............................... 1 Introduction. ............................. 2 Purpose and scope. ........................ 2 Physiographic and geologic setting ................ 4 Surface-water hydrology ........................ 5 Stream characteristics ...................... 5 Flood potential. ......................... 6 Regional ground-water hydrology .................... 16 Hydrogeologic units. ....................... 16 Lower clastic aquitard. ................... 25 Lower carbonate aquifer ..................
    [Show full text]
  • Licensing and Development of a Nuclear Waste Repository at Yucca
    PROGRAMMATIC AGREEMENT AMONG THE UNITED STATES DEPARTMENT OF ENERGY OFFICE OFCIVILIAN RADIOACTIVE WASTE MANAGEMENT, THE NEVADA STATE HISTORIC PRESERVATION OFFICE, AND THE ADVISORY COUNCIL ON HISTORIC PRESERVATION FOR LICENSING AND DEVELOPMENT OF A NUCLEAR WASTE REPOSITORY ATYUCCA MOUNTAIN, NYE COUNTY, NEVADA WHEREAS, Congress directed the U.S. Department of Energy (DOE) to characterize and evaluate the suitability of Yucca Mountain as a potential site for a repository for the disposal of spent nuclear fuel andhigh-level radioactive waste, and, if appropriate, construct and operate the facility; and WHEREAS, on July 23,2002, the President signed into law (Public Law 107-200) a joint resolution of the U.S. House of Representatives and the U.S. Senate designating the Yucca Mountain site in Nye County, Nevada, for development as a repository for the disposal of spent nuclear fuel and high-level radioactive waste; and WHEREAS, the DOE Office of Civilian Radioactive Waste Management (OCRWM) has submitted the application to the U.S.Nuclear Regulatory Commission (NRC) for authorization to construct a repository at Yucca Mountain, and the NRC has issued a notice of acceptance for docketingthis license application (73 FR 53284; September 15,2008); and WHEREAS, should the NRC grant a construction authorization for the proposed repository, the NRC may use this Agreement to fulfill its Section 106 obligations. If the NRC determines that it wants to become a party to this Agreement, it shall sign the agreement as an invited signatory and DOE shall be the lead Federal agency and act on the NRC's behalf, pursuant to 36 CFR Part 800.2(a)(2) of the Advisory Council on Historic Preservation's (ACHP) regulations implementing Section 106 of the National Historic Preservation Act (NHPA).
    [Show full text]
  • NEVADA LEGISLATURE LEGISLATIVE COMMITTEE on HIGH-LEVEL RADIOACTIVE WASTE (Nevada Revised Statutes [NRS] 459.0085)
    NEVADA LEGISLATURE LEGISLATIVE COMMITTEE ON HIGH-LEVEL RADIOACTIVE WASTE (Nevada Revised Statutes [NRS] 459.0085) SUMMARY MINUTES AND ACTION REPORT The first meeting of the Nevada Legislature’s Legislative Committee on High-Level Radioactive Waste was held on Friday, February 21, 2014, at 10 a.m. in Room 4412 of the Grant Sawyer State Office Building, 555 East Washington Avenue, Las Vegas, Nevada. The meeting was videoconferenced to Room 2135 of the Legislative Building, 401 South Carson Street, Carson City, Nevada. A copy of this set of “Summary Minutes and Action Report,” including the “Meeting Notice and Agenda” (Exhibit A) and other substantive exhibits, is available on the Nevada Legislature’s website at http://www.leg.state.nv.us/interim/77th2013/committee/. In addition, copies of the audio or video record are available through the Legislative Counsel Bureau’s Publications Office (e-mail: [email protected]; telephone: 775/684-6835). COMMITTEE MEMBERS PRESENT IN CARSON CITY: Assemblywoman Maggie Carlton, Chair Senator David R. Parks, Vice Chair Senator Pete Goicoechea Senator Ruben J. Kihuen Senator Patricia (Pat) Spearman Assemblyman Richard Carrillo Assemblyman Joseph M. Hogan Assemblyman James Oscarson LEGISLATIVE COUNSEL BUREAU STAFF PRESENT: Diane C. Thornton, Senior Research Analyst, Research Division Matthew S. Nichols, Principal Deputy Legislative Counsel, Legal Division Matt Mundy, Senior Deputy Legislative Counsel, Legal Division Gayle Nadeau, Senior Research Secretary, Research Division OPENING REMARKS AND INTRODUCTIONS • Assemblywoman Maggie Carlton, Chair, welcomed the public, announced the protocols for the meeting, and asked the Committee members to introduce themselves. PUBLIC COMMENT • Gary J. Duarte, resident, Sparks, Nevada, and Director, U.S.
    [Show full text]
  • DOÊY Yucca Mountain Studies
    DOÊY Yucca Mountain Studies D ’î 7.-*eUTIQN OF ТНЮ DOCUMENT « UNLIMITED DOE’s Yucca Mountain Studies U.S. Department of Energy YUCCA MOUNTAIN SITE CHARACTERIZATION PROJECT Post Office Box 98608 Las Vegas. NV 8919ЗД608 (702) 794-7900 Office of Civilian Radioactive Waste Management Education and Information Division (RW5) 1000 Independence Avenue, S.W. Washington. D C. 20585 (202) 586-2835 The iollowtnf number Is for OCRWM record* management pvrpewt only and ihould not be turd when ordering Ihis publication. Accession No.: HQO*9203U*00l0 DOE/RW-0349P • December 1992 ■ * C # ТНЛ DOCUMENT I« This booklet is about the disposal o f high-level nuclear waste in the United States. It is fo r readers who have a general rather than a technical background. It discusses wiy scientists and engineers think high-level nuclear waste may be disposed ofsaßly underground It also describes why Yucca Mountain, Nevada, is being studied as a potential repository site andprovides basic information about those studies. The question of how to dispose o f high-level nuclear waste safely has been a scientific andpublic concern since the beginning o f the nuclear age. The first commercial nuclear power plant in the United States began operation in 1957. Since then, the United States has come to rely on nuclear energy as a significant source o f electricity second only to coal Nuclear energy is used to make important contributions to mediane, research, and national security But the b erets o f nuclear power come coupled with great challenges. In this case, the challenge is the safo disposal o f radioactive waste.
    [Show full text]
  • Geology of the USW SD-9 Drill Hole, Yucca Mountain, Nevada
    MO 0100 (2) 1996 Revi«*v grr1 Apprnu-tl 761 ?- for PQE/n-cyrl. SANDIA REPORT £U SAND96-2030 • UC-814 • ft Unlimited Release Printed September 1996 Yucca Mountain Site Characterization Project Geology of the USW SD-9 Drill Hole, Yucca Mountain, Nevada D. A. Engstrom, Christopher A. Rautman Prepared by Sandia National Laboratories Albuquerque, New Mexico 87185 and Livermore, California 94550 for the United States Department of Energy under Contract DE-AC04-94AL85000 0 Approved for public release;|pfetni5ution is unlimited. DISTRIBUTION OF THIS DOCUME^ IS SF2900QI8-81) DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. "Prepared by Yucca Mountain Site Characterization Project (YMSCP) par- ticipants as part of the Civilian Radioactive Waste Management Program (CRWM). The YMSCP is managed by the Yucca Mountain Project Office of the U.S. Department of Energy, DOE Field Office, Nevada (DOE/NV). YMSCP work is sponsored by the Office of Geologic Repositories (OGR) of the DOE Office of Civilian Radioactive Waste Management (OCRWM)." Issued by Sandia National Laboratories, operated for the United States Department of Energy by Sandia Corporation. NOTICE: This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Govern- ment nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, prod- uct, or process disclosed, or represents that its use would not infringe pri- vately owned rights.
    [Show full text]
  • Yucca Mountain—Nevada's Perspective
    YUCCA MOUNTAIN—NEVADA’S PERSPECTIVE MARTA ADAMS* TABLE OF CONTENTS I. INTRODUCTION ........................................................................................... 1 II. SUMMARY.................................................................................................... 3 III. HISTORICAL BACKGROUND .................................................................. 6 A. Designation of Yucca Mountain as the Sole Site for Characterization .................................................................................... 7 B. Nuclear Energy Institute v. United States Environmental Protection Agency (NEI v. EPA) ........................................................ 12 C. Institutional Problems ......................................................................... 14 IV. PENDING LITIGATION ........................................................................... 12 A. Legal Challenges to the Current EPA and NRC Rules for Yucca Mountain .................................................................................. 16 B. Nevada‘s Water Case .......................................................................... 18 C. Nevada‘s Challenge to DOE‘s Transportation Decision ..................... 19 V. NRC‘S LICENSING PROCEEDING .......................................................... 20 A. Construction Authorization Review .................................................... 22 B. NRC Safety Review ............................................................................ 23 C. Hearing ...............................................................................................
    [Show full text]
  • Tectonic Evolution of the Crater Flat Basin, Yucca Mountain Region, Nevada
    U. S. DEPARTMENT OF THE INTERIOR U. S. GEOLOGICAL SURVEY Tectonic evolution of the Crater Flat basin, Yucca Mountain region, Nevada by C. J. Fridrich U. S. Geological Survey Box 25046, Denver, CO Open-File Report 98-33 Prepared in cooperation with the U. S. Department of Energy Yucca Mountain Site Characterization Project 1998 This report is preliminary and has not been reviewed for conformity with U. S. Geological Survey editorial standards. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U. S. Geological Survey. ABSTRACT Yucca Mountain is an arcuate, multiple-fault-block ridge on the rim of Crater Rat in southern Nevada. The ridge and alluvial flat are structurally linked and together constitute the Crater Flat structural basin. This late Cenozoic basin is located on the south flank of the southwest Nevada volcanic field, which in turn lies along the northeast margin of the Walker Lane belt, a northwest-trending zone of irregular topography and structure between the Sierra Nevada and the northern Basin and Range province. The Crater Flat basin is filled dominantly by the major ash-flow tuff sheets erupted from the central caldera complex of the volcanic field, at the north boundary of the basin. Relations in the volcanic rocks, including tilting, faulting, unit- thickness changes, and vertical-axis rotations, provide a detailed record of the tectonic history of Crater Flat and adjacent structural domains. Strata within Crater Flat basin are tilted dominantly eastward to southeastward along a closely spaced system of mostly west- to northwest-dipping normal faults.
    [Show full text]