Publications
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Topographic, bioclimatic, and vegetation characteristics of three ecoregion classification systems in North America: Comparisons along continent-wide transects
Ecoregion classification systems are increasingly used for policy and management decisions, particularly among conservation and natural resource managers. A number of ecoregion classification systems are currently available, with each system defining ecoregions using different classification methods and different types of data. As a result, each classification system describes a unique set of ecor
Authors
R.S. Thompson, S.L. Shafer, K. H. Anderson, L.E. Strickland, R.T. Pelltier, P. J. Bartlein, M.W. Kerwin
The Younger Dryas phase of Great Salt Lake, Utah, USA
Field investigations at the Public Shooting Grounds (a wildlife-management area on the northeastern shore of Great Salt Lake) and radiocarbon dating show that the Great Salt Lake rose to the Gilbert shoreline sometime between 12.9 and 11.2 cal ka. We interpret a ripple-laminated sand unit exposed at the Public Shooting Grounds, and dated to this time interval, as the nearshore sediments of Great S
Authors
Charles G. Oviatt, D. M. Miller, J. P. McGeehin, C. Zachary, S. Mahan
Magnetic mineralogy of sediments in Bear Lake and its watershed, Utah, Idaho, and Wyoming: Support for paleoenvironmental and paleomagnetic interpretations
No abstract available.
Authors
Richard L. Reynolds, Joseph G. Rosenbaum
U-Series isotopes as indicators of water/rock interaction in the unsaturated zone at Yucca Mountain, Nevada, USA
No abstract available.
Authors
James B. Paces, Leonid A. Neymark
Constraints on the geological history of the karst system in Southern Missouri, U.S.A. provided by radiogenic, cosmogenic and physical/chemical characteristics of doline fill
The Ozark Plateaus region of southern Missouri is underlain by dominantly carbonate marine platform rocks of Paleozoic age. The region has been sub-aerially exposed since the late Paleozoic and is characterized by extensive karst. To better understand the geologic history of this regional karst system, we examined the stratigraphic record preserved in the fill of a large doline near the largest sp
Authors
David J. Waery, Richard W. Harrison, Robert B. Jacobson, Milan P. Javich, Shannon A. Mahan, David Wronkiewicz
Environments of northwestern North America before the last glacial maximum
No abstract available.
Authors
John J. Clague, Rolf Mathewes, Thomas A. Ager
Topogrid Derived 10 Meter Resolution Digital Elevation Model of the Shenandoah National Park and Surrounding Region, Virginia
Explanation
The purpose of developing a new 10m resolution DEM of the Shenandoah National Park Region was to more accurately depict geologic structure, surfical geology, and landforms of the Shenandoah National Park Region in preparation for automated landform classification. Previously, only a 30m resolution DEM was available through the National Elevation Dataset (NED). During production of t
Authors
Peter G. Chirico, Seth D. Tanner
Reply to the letter to the editor from Huntley re Mayer and Mahan, 2004. Quaternary Research 61, 72–84
No abstract available.
Authors
J. H. Mayer, Shannon A. Mahan
Reply to the comment on “Physical and stable-isotope evidence for formation of secondary calcite and silica in the unsaturated zone, Yucca Mountain, Nevada”, by Y.V. Dublyansky, S.E. Smirnov and G.P. Palyanova
No abstract available.
Authors
Joseph F. Whelan, James B. Paces, Zell E. Peterman, Brian D. Marshall, Leonid A. Neymark
The geochemical and magnetic record of coal combustion products in West Virginia reservoir sediments and soils
Western West Virginia lies downwind from numerous coal-fired power plants along the Ohio River Valley. To test whether geochemical and mineralogical impacts from these power plants are detectable on the West Virginia landscape, we obtained reservoir cores, soils, and rocks from two separate sites in West Virginia, one in Harrison County (Hinkel and Deegan Reservoirs) and the other in Roane County
Authors
Martin B. Goldhaber, Ted Callender, Richard L. Reynolds
Geology of Gunnison Gorge National Conservation Area, Delta and Montrose Counties, Colorado
No abstract available.
Authors
Karl S. Kellogg, Wallace R. Hansen, Karen S. Tucker, D. Paco VanSistine
Reply to discussion on “Tectonic controls of Mississippi Valley-type lead–zinc mineralization in orogenic forelands”
Bradley and Leach (2003) focused on the tectonics of a subset of Mississippi Valley-type (MVT) lead–zinc deposits. Age assignments followed those given in a review of MVT deposits worldwide (Leach et al. 2001)—a paper that provoked a discussion by Kesler and Carrigan (2002) and reply by Leach et al. (2002), similar to the present exchange. While the new discussion by Kesler et al. (2004) does addr
Authors
Dwight Bradley, David L. Leach, David Symons, Poul Emsbo, Wayne R. Premo, George N. Breit, D. F. Sangster