Publications
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Late Quaternary stratigraphy and geochronology of the western Killpecker Dunes, Wyoming, USA Late Quaternary stratigraphy and geochronology of the western Killpecker Dunes, Wyoming, USA
New stratigraphic and geochronologic data from the Killpecker Dunes in southwestern Wyoming facilitate a more precise understanding of the dune field's history. Prior investigations suggested that evidence for late Pleistocene eolian activity in the dune field was lacking. However, luminescence ages from eolian sand of ???15,000 yr, as well as Folsom (12,950-11,950 cal yr B.P.) and Agate...
Authors
J. H. Mayer, S. A. Mahan
Composition, dynamics, and fate of leached dissolved organic matter in terrestrial ecosystems: Results from a decomposition experiment Composition, dynamics, and fate of leached dissolved organic matter in terrestrial ecosystems: Results from a decomposition experiment
Fluxes of dissolved organic matter (DOM) are an important vector for the movement of carbon (C) and nutrients both within and between ecosystems. However, although DOM fluxes from throughfall and through litterfall can be large, little is known about the fate of DOM leached from plant canopies, or from the litter layer into the soil horizon. In this study, our objectives were to...
Authors
C.C. Cleveland, J. C. Neff, A.R. Townsend, E. Hood
Three-dimensional geologic framework modeling of faulted hydrostratigraphic units within the Edwards aquifer, northern Bexar County, Texas Three-dimensional geologic framework modeling of faulted hydrostratigraphic units within the Edwards aquifer, northern Bexar County, Texas
This report includes a digital, three-dimensional (3-D) faulted hydrostratigraphic model we have constructed to represent the geologic framework of the Edwards aquifer system in the area of San Antonio, northern Bexar County, Texas. The model is based on mapped geologic relationships that reflect the complex structures of the Balcones fault zone, detailed lithologic descriptions and
Authors
Michael P. Pantea, J. C. Cole
Late Quaternary glaciation of the Upper Soca River Region (Southern Julian Alps, NW Slovenia) Late Quaternary glaciation of the Upper Soca River Region (Southern Julian Alps, NW Slovenia)
Extent of Late Quaternary glaciers in the Upper Soc??a River Region (Southern Julian Alps, SE Europe) has been analyzed using a combination of geological mapping, glaciological modeling, and sediment dating (radiocarbon, U/Th series and Infrared Stimulated Luminescence-IRSL). Field investigations focused mainly on relatively well preserved Quaternary sequences in the Bovec Basin, an...
Authors
Milos Bavec, Slawek M. Tulaczyk, Shannon Mahan, Gregory M. Stock
Use of naturally occurring mercury to determine the importance of cutthroat trout to Yellowstone grizzly bears Use of naturally occurring mercury to determine the importance of cutthroat trout to Yellowstone grizzly bears
Spawning cutthroat trout (Oncorhynchus clarki (Richardson, 1836)) are a potentially important food resource for grizzly bears (Ursus arctos horribilis Ord, 1815) in the Greater Yellowstone Ecosystem. We developed a method to estimate the amount of cutthroat trout ingested by grizzly bears living in the Yellowstone Lake area. The method utilized (i) the relatively high, naturally...
Authors
L.A. Felicetti, C.C. Schwartz, R. O. Rye, K.A. Gunther, J.G. Crock, M.A. Haroldson, L. Waits, C.T. Robbins
Isotopic, geochemical, and temporal characterization of Proterozoic basement rocks in the Quitovac region, northwestern Sonora, Mexico: Implications for the reconstruction of the southwestern margin of Laurentia Isotopic, geochemical, and temporal characterization of Proterozoic basement rocks in the Quitovac region, northwestern Sonora, Mexico: Implications for the reconstruction of the southwestern margin of Laurentia
A detailed geochemical characterization of 19 representative Proterozoic basement rocks in the Quitovac region in northwestern Sonora, Mexico, has identified two distinct Paleoproterozoic basement blocks that coincide spatially with the previously proposed Caborca and "North America" blocks. New U-Pb zircon geochronology revises their age ranges, the Caborca (1.78-1.69 Ga) and "North...
Authors
A. Iriondo, W. R. Premo, Luis M. Martinez-Torres, J. R. Budahn, William W. Atkinson, D. F. Siems, B. Guaras-Gonzalez
Geochemistry of dust in the Exploratory Studies Facility, Yucca Mountain, Nevada Geochemistry of dust in the Exploratory Studies Facility, Yucca Mountain, Nevada
No abstract available.
Authors
Zell E. Peterman, James B. Paces, Leonid A. Neymark, D. Hudson
Summary of Chlorine-36 validation studies at Yucca Mountain, Nevada Summary of Chlorine-36 validation studies at Yucca Mountain, Nevada
No abstract available.
Authors
James B. Paces, Zell E. Peterman, Leonid A. Neymark, G. J. Nimz, M. Gascoyne, Brian D. Marshall
U-series disequilibrium as a test for unsaturated-zone hydrologic models at Yucca Mountain, Nevada U-series disequilibrium as a test for unsaturated-zone hydrologic models at Yucca Mountain, Nevada
No abstract available.
Authors
James B. Paces, Leonid A. Neymark
Reliability of U-Th-Pb dating of secondary silica at Yucca Mountain, Nevada Reliability of U-Th-Pb dating of secondary silica at Yucca Mountain, Nevada
No abstract available.
Authors
Leonid A. Neymark, James B. Paces, Y. V. Amelin
The Rocky Mountain glacial model; the Wind River Range, Wyoming The Rocky Mountain glacial model; the Wind River Range, Wyoming
No abstract available.
Authors
D. E. Dahms, R. D. Hall, Ralph R. Shroba, C. J. Sorenson, E. A. Lynch, M. T. Applegarth
Quaternary vegetation and climate change in the western United States: Developments, perspectives, and prospects Quaternary vegetation and climate change in the western United States: Developments, perspectives, and prospects
This chapter explores the strengths and shortcomings of the major sources of data on Quaternary vegetation and climate change and discusses the use of models as a means to explore past and potential future environmental changes. The flora and major vegetation types of the western United States are present for several million years. Ongoing changes in atmospheric chemistry, climate, and...
Authors
Robert S. Thompson, Sarah Shafer, Laura E. Strickland, Peter K. Van De Water, Katherine H. Anderson