Publications
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Improving paleoecology studies for future predictions: Role of spatial and temporal scales for understanding ecology of the arid and semiarid landscape of the Southwest
Paleoecology (or ecological biogeography) describes the past distribution of species or communities and is an informative path used to understand the future in the face of climate change. Paleoecological changes in the Southwest over the past several thousand years happened in the presence of landscape manipulations by humans, a factor that adds relevance but increases difficulty of interpretation
Authors
David M. Miller, Gene-Hua Crystal Ng, Katharine Maher
Gravity, aeromagnetic and rock-property data of the central California Coast Ranges
Gravity, aeromagnetic, and rock-property data were collected to support geologic-mapping, water-resource, and seismic-hazard studies for the central California Coast Ranges. These data are combined with existing data to provide gravity, aeromagnetic, and physical-property datasets for this region. The gravity dataset consists of approximately 18,000 measurements. The aeromagnetic dataset consists
Authors
V. E. Langenheim
Rock-Eval pyrolysis and vitrinite reflectance results from the Sheep Creek 1 well, Susitna basin, south-central Alaska
We used Rock-Eval pyrolysis and vitrinite reflectance to examine the petroleum source potential of rock samples from the Sheep Creek 1 well in the Susitna basin of south-central Alaska. The results show that Miocene nonmarine coal, carbonaceous shale, and mudstone are potential sources of hydrocarbons and are thermally immature with respect to the oil window. In the samples that we studied, coals
Authors
Richard G. Stanley, Paul G. Lillis, Mark J. Pawlewicz, Peter J. Haeussler
By
Energy and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Alaska Science Center, Central Energy Resources Science Center, Geology, Minerals, Energy, and Geophysics Science Center
Arsenic speciation in solids using X-ray absorption spectroscopy
Synchrotron-based X-ray absorption spectroscopy (XAS) is an in situ, minimally-destructive, element-specific, molecular-scale structural probe that has been employed to study the chemical forms (species) of arsenic (As) in solid and aqueous phases (including rocks, soils, sediment, synthetic compounds, and numerous types of biota including humans) for more than 20 years. Although several excellent
Authors
Andrea L. Foster, Chris S. Kim
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 shifting d
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, Iñigo Losada, José Marengo, Roger McLean, Linda Mearns, Reinhard Mechler, John Morton, Isabelle Niang, Taikan Oki, Jane Mukarugwiza Olwoch, Maggie Opondo, Elvira Poloczanska, Hans -O. Pörtner, Andy Reisinger, Aromar Revi, Daniela Schmidt, Rebecca Shaw, William Solecki, Dáithí 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
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. Gravity highs
Authors
Victoria E. Langenheim, R.Q. Oaks, H. Willis, A.I. Hiscock, Bruce A. Chuchel, Jose J. Rosario, C.L. Hardwick
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 identify
Authors
Jonathan M.G. Glen, Darcy McPhee, Paul A. Bedrosian
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 gravity anoma
Authors
Richard J. Blakely, Brian L. Sherrod, Craig S. Weaver, Ray Wells, Alan C. Rohay
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 that is at l
Authors
Victoria E. Langenheim, Noah D. Athens, Daniel S. Scheirer, Gary S. Fuis, Michael J. Rymer, Mark R. Goldman
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 provided in the
Authors
Matthew K. Burgess, Paul A. Bedrosian
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 southwestern boundar
Authors
Darcy McPhee, Victoria E. Langenheim, Ray Wells, Richard J. Blakely
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 observations an
Authors
Magdalena A Ellis, Barnes Jason B, Joseph Colgan
By
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