Publications
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Cenozoic tectonic reorganizations of the Death Valley region, southeast California and southwest Nevada
The Death Valley region, of southeast California and southwest Nevada, is distinct relative to adjacent regions in its structural style and resulting topography, as well as in the timing of basin-range extension. Cenozoic basin-fill strata, ranging in age from greater than or equal to 40 to approximately 2 million years are common within mountain-range uplifts in this region. The tectonic fragment
Authors
Christopher J. Fridrich, Ren A. Thompson
Aeolian and fluvial processes in dryland regions: The need for integrated studies
Aeolian and fluvial processes play a fundamental role in dryland regions of the world and have important environmental and ecological consequences from local to global scales. Although both processes operate over similar spatial and temporal scales and are likely strongly coupled in many dryland systems, aeolian and fluvial processes have traditionally been studied separately, making it difficult
Authors
Jayne Belnap, Seth M. Munson, Jason P. Field
Summary of the stratigraphy and structural elements related to plate convergence of the Quetta-Muslim Bagh-Sibi region, Balochistan, west-central Pakistan
Obduction of an ophiolite complex onto the northwestern continental margin of the India plate occurred during the Late Cretaceous to early Paleocene, followed by collision of the ophiolitic complex of the India plate with the Eurasia plate in the Eocene. Lower Eocene marine strata overlie the ophiolitic complex suggesting that suturing was completed by early Eocene time.
The Quetta-Muslim Bagh-Sib
Authors
Florian Maldonado, Jan M. Mengal, Shahid H. Khan, Peter D. Warwick
U.S. Geological Survey Science for the Wyoming Landscape Conservation Initiative-2010 Annual Report
This is the third report produced by the U.S. Geological Survey (USGS) for the Wyoming Landscape Conservation Initiative (WLCI) to detail annual work activities. The first report described activities for 2007 and 2008, and the second report covered work activities for FY09. This third report covers work activities conducted in FY2010, and it continues the 2009 approach of reporting on all the indi
Authors
Zachary H. Bowen, Cameron L. Aldridge, Patrick J. Anderson, Timothy J. Assal, Laura Biewick, Steven W. Blecker, Gregory K. Boughton, R. Sky Bristol, Natasha B. Carr, Anna D. Chalfoun, Geneva W. Chong, Melanie L. Clark, Jay E. Diffendorfer, Bradley C. Fedy, Katharine Foster, Steven L. Garman, Steve Germaine, JoAnn Holloway, Collin G. Homer, Matthew J. Kauffman, Douglas Keinath, Natalie Latysh, Daniel J. Manier, Robert R. McDougal, Cynthia P. Melcher, Kirk A. Miller, Jessica Montag, Christopher J. Potter, Spencer Schell, Sarah L. Shafer, David B. Smith, Lisa L. Stillings, Michele L. Tuttle, Anna B. Wilson
Geospatial Multi-Agency Coordination (GeoMAC) wildland fire perimeters, 2008
The Geospatial Multi-Agency Coordination (GeoMAC) has been collecting and storing data on wildland fire perimeters since August 2000. The dataset presented via this U.S. Geological Survey Data Series product contains the GeoMAC wildland fire perimeter data for the calendar year 2008, which are based upon input from incident intelligence sources, Global Positioning System (GPS) data, and infrared (
Authors
Sandra P. Walters, Norma J. Schneider, John D. Guthrie
Deglaciation and postglacial treeline fluctuation in the northern San Juan Mountains, Colorado
The San Juan Mountains of southwestern Colorado contain numerous lakes and bogs at and above treeline. In June 1978, Lake Emma, a tarn above present-day treeline, was suddenly drained by the collapse of underground mine workings. This study was initiated because the draining exposed a well-preserved archive of subfossil coniferous wood fragments that provided a unique opportunity to further our un
Authors
Paul E. Carrara
Identification of last interglacial deposits in eastern Beringia: a cautionary note from the Palisades, interior Alaska
Last interglacial sediments in unglaciated Alaska and Yukon (eastern Beringia) are commonly identified by palaeoecological indicators and stratigraphic position ~2-5m above the regionally prominent Old Crow tephra (124 + or - 10ka). We demonstrate that this approach can yield erroneous age assignments using data from a new exposure at the Palisades, a site in interior Alaska with numerous exposure
Authors
Alberto V. Reyes, Grant D. Zazula, Svetlana Kuzmina, Thomas A. Ager, Duane G. Froese
Physical, chemical, and mineralogical data from surficial deposits, groundwater levels, and water composition in the area of Franklin Lake playa and Ash Meadows, California and Nevada
This report presents data and describes the methods used to determine the physical attributes, as well as the chemical and mineralogical composition of surficial deposits; groundwater levels; and water composition in the area of Franklin Lake playa and Ash Meadows, California and Nevada.
The results support studies that examine (1) the interaction between groundwater and the ground surface, and t
Authors
Harland L. Goldstein, George N. Breit, James C. Yount, Richard L. Reynolds, Marith C. Reheis, Gary L. Skipp, Eric M. Fisher, Paul J. Lamothe
Assessing open-system behavior of 14C in terrestrial gastropod shells
In order to assess open-system behavior of radiocarbon in fossil gastropod shells, we measured the 14C activity on 10 aliquots of shell material recovered from Illinoian (~190–130 ka) and pre-Illinoian (~800 ka) loess and lacustrine deposits in the Midwestern USA. Eight of the 10 aliquots yielded measurable 14C activities that ranged from 0.25 to 0.53 percent modern carbon (pMC), corresponding to
Authors
Jason A. Rech, Jeffrey S. Pigati, Sophie B. Lehmann, Chelsea N. McGimpsey, David A. Grimley, Jeffrey C. Nekola
A loess–paleosol record of climate and glacial history over the past two glacial–interglacial cycles (~ 150 ka), southern Jackson Hole, Wyoming
Loess accumulated on a Bull Lake outwash terrace of Marine Oxygen Isotope Stage 6 (MIS 6) age in southern Jackson Hole, Wyoming. The 9 m section displays eight intervals of loess deposition (Loess 1 to Loess 8, oldest), each followed by soil development. Our age-depth model is constrained by thermoluminescence, meteoric 10Be accumulation in soils, and cosmogenic 10Be surface exposure ages. We use
Authors
Kenneth L. Pierce, Daniel R. Muhs, Maynard A. Fosberg, Shannon A. Mahan, Joseph G. Rosenbaum, Joseph M. Licciardi, Milan J. Pavich
Seasonal dynamics of CO2 profiles across a soil chronosequence, Santa Cruz, California
Concentrations of CO2 in soil atmosphere and CO2 efflux were measured across a marine terrace soil chronosequence near Santa Cruz, California. Soil development, specifically the formation of an argillic horizon, has created a two-tier soil gas profile in the older terrace soils. The soil above the argillic horizon has seasonal variations in soil CO2 associated with plant respiration. The older soi
Authors
Marjorie S. Schulz, David A. Stonestrom, Guntram von Kiparski, Corey R. Lawrence, C.A. Masiello, Arthur F. White, John Fitzpatrick
Assessing effects of energy development in Colorado and New Mexico
No abstract available.
Authors
N.B. Carr, J.E. Diffendorfer, N.E. Latysh, K.J. Leib, Anne-Marie Matherne, Christine Turner