Publications
Filter Total Items: 1151
Time-domain electromagnetic surveys at Fort Irwin, San Bernardino County, California, 2010–12 Time-domain electromagnetic surveys at Fort Irwin, San Bernardino County, California, 2010–12
Between 2010 and 2012, a total of 79 time-domain electromagnetic (TEM) soundings were collected in 12 groundwater basins in the U.S. Army Fort Irwin National Training Center (NTC) study area to help improve the understanding of the hydrogeology of the NTC. The TEM data are discussed in this chapter in the context of geologic observations of the study area, the details of which are...
Authors
Matthew K. Burgess, Paul A. Bedrosian
Width and dip of the southern San Andreas Fault at Salt Creek from modeling of geophysical data Width and dip of the southern San Andreas Fault at Salt Creek from modeling of geophysical data
We investigate the geometry and width of the southernmost stretch of the San Andreas Fault zone using new gravity and magnetic data along line 7 of the Salton Seismic Imaging Project. In the Salt Creek area of Durmid Hill, the San Andreas Fault coincides with a complex magnetic signature, with high-amplitude, short-wavelength magnetic anomalies superposed on a broader magnetic anomaly...
Authors
Victoria E. Langenheim, Noah D. Athens, Daniel S. Scheirer, Gary S. Fuis, Michael J. Rymer, Mark R. Goldman
40Ar/39Ar geochronology, paleomagnetism, and evolution of the Boring volcanic field, Oregon and Washington, USA 40Ar/39Ar geochronology, paleomagnetism, and evolution of the Boring volcanic field, Oregon and Washington, USA
The 40Ar/39Ar investigations of a large suite of fine-grained basaltic rocks of the Boring volcanic field (BVF), Oregon and Washington (USA), yielded two primary results. (1) Using age control from paleomagnetic polarity, stratigraphy, and available plateau ages, 40Ar/39Ar recoil model ages are defined that provide reliable age results in the absence of an age plateau, even in cases of...
Authors
Robert J. Fleck, Jonathan T. Hagstrum, Andrew T. Calvert, Russell C. Evarts, Richard M. Conrey
By
Geology, Energy, and Minerals Mission Area, Natural Hazards Mission Area, Energy Resources Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Volcano Hazards Program, Volcano Science Center, Geology, Minerals, Energy, and Geophysics Science Center
Preliminary isostatic residual gravity map of the Tremonton 30' x 60' quadrangle, Box Elder and Cache Counties, Utah, and Franklin and Oneida Counties, Idaho Preliminary isostatic residual gravity map of the Tremonton 30' x 60' quadrangle, Box Elder and Cache Counties, Utah, and Franklin and Oneida Counties, Idaho
A new isostatic residual gravity map of the Tremonton 30' x 60' quadrangle of Utah is based on compilation of preexisting data and new data collected by the Utah and U.S. Geological Surveys. Pronounced gravity lows occur over North Bay, northwest of Brigham City, and Malad and Blue Creek Valleys, indicating significant thickness of low-density Tertiary sedimentary rocks and deposits...
Authors
Victoria E. Langenheim, R.Q. Oaks, H. Willis, A.I. Hiscock, Bruce A. Chuchel, Jose J. Rosario, C.L. Hardwick
The Wallula fault and tectonic framework of south-central Washington, as interpreted from magnetic and gravity anomalies The Wallula fault and tectonic framework of south-central Washington, as interpreted from magnetic and gravity anomalies
The Yakima fold and thrust belt (YFTB) in central Washington has accommodated regional, mostly north-directed, deformation of the Cascadia backarc since prior to emplacement of Miocene flood basalt of the Columbia River Basalt Group (CRBG). The YFTB consists of two structural domains. Northern folds of the YFTB strike eastward and terminate at the western margin of a 20-mGal negative...
Authors
Richard J. Blakely, Brian Sherrod, Craig S. Weaver, Ray E. Wells, Alan C. Rohay
Tectonic evolution of the Tualatin basin, northwest Oregon, as revealed by inversion of gravity data Tectonic evolution of the Tualatin basin, northwest Oregon, as revealed by inversion of gravity data
The Tualatin basin, west of Portland (Oregon, USA), coincides with a 110 mGal gravity low along the Puget-Willamette lowland. New gravity measurements (n = 3000) reveal a three-dimensional (3-D) subsurface geometry suggesting early development as a fault-bounded pull-apart basin. A strong northwest-trending gravity gradient coincides with the Gales Creek fault, which forms the...
Authors
Darcy McPhee, Victoria E. Langenheim, Ray E. Wells, Richard J. Blakely
Geomorphic evidence for enhanced Pliocene-Quaternary faulting in the northwestern Basin and Range Geomorphic evidence for enhanced Pliocene-Quaternary faulting in the northwestern Basin and Range
Mountains in the U.S. Basin and Range Province are similar in form, yet they have different histories of deformation and uplift. Unfortunately, chronicling fault slip with techniques like thermochronology and geodetics can still leave sizable, yet potentially important gaps at Pliocene–Quaternary (∼105–106 yr) time scales. Here, we combine existing geochronology with new geomorphic...
Authors
Magdalena A Ellis, Barnes Jason B, Joseph P. Colgan
By
Geology, Energy, and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center
Geophysical investigations of the geologic and hydrothermal framework of the Pilgrim Springs Geothermal Area, Alaska Geophysical investigations of the geologic and hydrothermal framework of the Pilgrim Springs Geothermal Area, Alaska
Pilgrim Hot Springs, located on the Seward Peninsula in west-central Alaska, is characterized by hot springs, surrounding thawed regions, and elevated lake temperatures. The area is of interest because of its potential for providing renewable energy for Nome and nearby rural communities. We performed ground and airborne geophysical investigations of the Pilgrim Springs geothermal area to...
Authors
Jonathan M.G. Glen, Darcy McPhee, Paul A. Bedrosian
Geophysical framework of the Peninsular Ranges batholith—Implications for tectonic evolution and neotectonics Geophysical framework of the Peninsular Ranges batholith—Implications for tectonic evolution and neotectonics
The crustal structure of the Peninsular Ranges batholith can be divided geophysically into two parts: (1) a western mafic part that is dense, magnetic, and characterized by relatively high seismic velocities (>6.25 km/s), low heat flow (
Authors
Victoria E. Langenheim, Robert C. Jachens, Carlos Aiken
Climate Change 2014: Technical Summary Climate Change 2014: Technical Summary
Human interference with the climate system is occurring (WGI AR5 SPM Section D.3; WGI AR5 Sections 2.2, 6.3, 10.3 to 10.6, 10.9). Climate change poses risks for human and natural systems. The assessment of impacts, adaptation, and vulnerability in the Working Group II contribution to the IPCC’s Fifth Assessment Report (WGII AR5) evaluates how patterns of risks and potential benefits are...
Authors
Chrisopher B. Field, Vicente Barros, Katherine Mach, Michael Mastrandrea, Maarten van Aalst, Niel Adger, Douglas J Arent, Jonathan Barnett, Richard Betts, Eren Bilir, Joern Birkmann, Joann Carmin, Dave Chadee, Andrew Challinor, Monalisa Chaterjee, Wolfgang Cramer, Debra Davidson, Yuka Estrada, Jean-Pierre Gatusso, Yasuakai Hijioka, Gary Yohe, Margaret Hiza, Ove Hoegh-Guldberg, He-Qing Huang, Gregory Insarov, Roger Jones, Sari Kovats, Patricia Romero Lankao, Joan Nymand Larsen, Inigo Losada, Jose Marengo, Roger McLean, Linda Mearns, Reinhard Mechler, John Morton, Isabelle Niang, Taikan Oki, Jane Mukarugwiza Olwoch, Maggie Opondo, Elvira Poloczanska, Hans #NAME? Portner, Andy Reisinger, Aromar Revi, Daniela Schmidt, Rebecca Shaw, William Solecki, Daithi Stone, John Stone, Ken Strzepek, Avelino G. Suarez, Petra Tschakert, Riccardo Valentini, Sebastian Vicuna, Alicia Villamizar, Katharine Vincent, Rachel Warren, Leslie White, Thomas Wilbanks, Poh Poh Wong
Magmatism, ash-flow tuffs, and calderas of the ignimbrite flareup in the western Nevada volcanic field, Great Basin, USA Magmatism, ash-flow tuffs, and calderas of the ignimbrite flareup in the western Nevada volcanic field, Great Basin, USA
The western Nevada volcanic field is the western third of a belt of calderas through Nevada and western Utah. Twenty-three calderas and their caldera-forming tuffs are reasonably well identified in the western Nevada volcanic field, and the presence of at least another 14 areally extensive, apparently voluminous ash-flow tuffs whose sources are unknown suggests a similar number of...
Authors
Christopher D. Henry, David A. John
Undiscovered gas resources in the Alum Shale, Denmark, 2013 Undiscovered gas resources in the Alum Shale, Denmark, 2013
Using a geology-based assessment methodology, the U.S. Geological Survey estimates a mean undiscovered volume of 6.9 trillion cubic feet of natural gas in the Alum Shale in Denmark.
Authors
Donald L. Gautier, Ronald R. Charpentier, Stephanie B. Gaswirth, Timothy R. Klett, Janet K. Pitman, Christopher J. Schenk, Marilyn E. Tennyson, Katherine J. Whidden
By
Geology, Energy, and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Central Energy Resources Science Center, Geology, Minerals, Energy, and Geophysics Science Center