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National Geochemical Database, U.S. Geological Survey RASS (Rock Analysis Storage System) geochemical data for Alaska
E. A. Bailey, D. B. Smith, C. C. Abston, Matthew Granitto, K. A. Burleigh
2000, Open-File Report 99-433
This dataset contains geochemical data for Alaska produced by the analytical laboratories of the Geologic Division of the U.S. Geological Survey (USGS). These data represent analyses of stream-sediment, heavy-mineral-concentrate (derived from stream sediment), soil, and organic material samples. Most of the data comes from mineral resource investigations conducted in the...
TES observations of the martian surface and atmosphere
P. R. Christensen, H. H. Kieffer, J.C. Pearl, B. Conrath, M. C. Malin, R.C. Clark, R.V. Morris, J.L. Banfield, M. D. Lane, M. D. Smith, V.E. Hamilton, R.O. Kuzmin
2000, Book, Second International Conference on Mars Polar Science and Exploration
The TES instrument is a Fourier transform Michelson interferometer operating with 10 or 5 cm-1 sampling int he thermal infared spectral region from 1700 to 200 cm-1 (~6 to 50 μm) where virtually all minerals have characteristic fundamental vibrational absorption bands (1, 2, 3, 4, 5, 6, 7, 8). The...
Relationship of Eastern hemlock (Tsuga canadensis) to the ecology of small streams in Delaware Water Gap National Recreation Area
David P. Lemarie, John A. Young, Craig D. Snyder, Robert M. Ross, David Smith, Randy M. Bennett
2000, General Technical Report NE-267
Hemlock ravines in Delaware Water Gap National Recreation Area (DEWA) are highly valued because of their distinctive aesthetic, recreational and ecological qualities. We conducted a comparative study designed to determine the potential long-term consequences to aquatic communities of the suspected transition from hemlock-dominated forests to mixed hardwood forests as a result of hemlock woolly adelgid (HWA; Adelges...
The state and future of Mars polar science and exploration
S.M. Clifford, D. Crisp, D.A. Fisher, Kenneth E. Herkenhoff, S.E. Smrekar, P. C. Thomas, D. D. Wynn-Williams, R.W. Zurek, J.R. Barnes, B.G. Bills, E.W. Blake, W. M. Calvin, J.M. Cameron, M. H. Carr, P. R. Christensen, B. C. Clark, G.D. Clow, J.A. Cutts, D. Dahl-Jensen, W.B. Durham, F. P. Fanale, J.D. Farmer, F. Forget, K. Gotto-Azuma, R. Grard, R.M. Haberle, W. Harrison, R. Harvey, A.D. Howard, A.P. Ingersoll, P.B. James, J.S. Kargel, H. H. Kieffer, J. Larsen, K. Lepper, M. C. Malin, D. J. McCleese, B. Murray, J.F. Nye, D. A. Paige, S.R. Platt, J.J. Plaut, N. Reeh, J.W. Rice, D.E. Smith, C. R. Stoker, K. L. Tanaka, E. Mosley-Thompson, T. Thorsteinsson, S.E. Wood, A. Zent, M.T. Zuber, H.J. Zwally
2000, Icarus (144) 210-242
As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ∼106 km2 and total as much as 3–4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to be comparatively young—preserving a...
Addendum to `numerical modeling of an enhanced very early time electromagnetic (VETEM) prototype system'
T.J. Cui, W.C. Chew, A.A. Aydiner, D.L. Wright, D.V. Smith, J.D. Abraham
2000, IEEE Antennas and Propagation Magazine (42) 54-57
Two numerical models to simulate an enhanced very early time electromagnetic (VETEM) prototype system that is used for buried-object detection and environmental problems are presented. In the first model, the transmitting and receiving loop antennas accurately analyzed using the method of moments (MoM), and then conjugate gradient (CG) methods with...
Environmental geochemistry at the global scale
J. Plant, D. Smith, B. Smith, L. Williams
2000, Journal of the Geological Society (157) 837-849
Land degradation and pollution caused by population pressure and economic development pose a threat to the sustainability of the Earth's surface, especially in tropical regions where a long history of chemical weathering has made the surface environment particularly fragile. Systematic baseline geochemical data provide a means of monitoring the state...
Wolf-bison interactions in Yellowstone National Park
Douglas W. Smith, L. David Mech, Mary Meagher, Wendy E. Clark, Rosemary Jaffe, Michael K. Phillips, John A. Mack
2000, Journal of Mammalogy (81) 1128-1135
We studied interactions of reintroduced wolves (Canis lupus) with bison (Bison bison) in Yellowstone National Park. Only 2 of 41 wolves in this study had been exposed to bison before their translocation. Wolves were more successful killing elk (Cervus elaphus) than bison, and elk were more abundant than bison, so...
Geologic setting of the Fortymile River area - Polyphase deformational history within part of the eastern Yukon-Tanana uplands of Alaska: A section in Geologic studies in Alaska by the U.S. Geological Survey, 1998
Warren C. Day, Bruce M. Gamble, Mitchell W. Henning, Bruce D. Smith
2000, Professional Paper 1615
The Fortymile River area lies within the Yukon-Tanana lithotectonic terrane of east-central Alaska. This terrane is a mosaic of several lithotectonic assemblages, each with a coherent lithologic, metamorphic, and deformational history. Previous workers have shown that the Fortymile River area is underlain by rocks of the Seventymile, Taylor Mountain, and...
Numerical modeling of an enhanced very early time electromagnetic (VETEM) prototype system
T.J. Cui, W.C. Chew, A.A. Aydiner, D.L. Wright, D.V. Smith, J.D. Abraham
2000, IEEE Antennas and Propagation Magazine (42) 17-27
In this paper, two numerical models are presented to simulate an enhanced very early time electromagnetic (VETEM) prototype system, which is used for buried-object detection and environmental problems. Usually, the VETEM system contains a transmitting loop antenna and a receiving loop antenna, which run on a lossy ground to detect...
Identification of a basaltic component on the Martian surface from Thermal Emission Spectrometer data
P. R. Christensen, J. L. Bandfield, M. D. Smith, V.E. Hamilton, Roger N. Clark
2000, Journal of Geophysical Research: Planets (105) 9609-9621
The Mars Global Surveyor Thermal Emission Spectrometer (TES) instrument collected 4.8×106 spectra of Mars during the initial aerobraking and science‐phasing periods of the mission (September 14, 1997, through April 29, 1998). Two previously developed atmosphere‐removal models were applied to data from Cimmeria Terra (25°S, 213°W). The surface spectra derived for these...
Imaging and modeling new VETEM data
David L. Wright, David V. Smith, Jared D. Abraham, Raymond S. Hutton, E. Kent Bond, Tie Jun Cui, Alaeddin A. Aydiner, Weng Cho Chew
2000, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
In previously reported work (Wright and others, 2000) we found that the very early time electromagnetic (VETEM) prototype system produced data from which high resolution images of a buried former foundry site at the Denver Federal Center were made. The soil covering the site is about 30 mS/m conductivity, and...
Detection of crystalline hematite mineralization on Mars by the Thermal Emission Spectrometer: evidence for near-surface water
P. R. Christensen, J. L. Bandfield, R. N. Clark, K.S. Edgett, V.E. Hamilton, T. Hoefen, H. H. Kieffer, R.O. Kuzmin, M. D. Lane, M. C. Malin, R.V. Morris, J.C. Pearl, R. Pearson, T. L. Roush, S. W. Ruff, M. D. Smith
2000, Journal of Geophysical Research E: Planets (105) 9623-9642
The Thermal Emission Spectrometer (TES) instrument on the Mars Global Surveyor (MGS) mission has discovered a remarkable accumulation of crystalline hematite (α-Fe2O3) that covers an area with very sharp boundaries approximately 350 by 350–750 km in size centered near 2°S latitude between 0° and 5°W longitude (Sinus Meridiani). Crystalline hematite...
Influence of temperature and substrate on infection rate, triactinomyxon production, and release duration from eastern tubifex worms infected with Myxobolus cerebralis
Thomas Waldrop, Vicki Blazer, David Smith, Bane Schill, Christine Densmore
B. Schill, T. Waldrop, V. Blazer, editor(s)
1999, Book, 5th Annual Whirling Disease Symposium: Research and Management Perspectives
Salmonid whirling disease is caused by Myxobolus cerebralis, a metazoan parasite with a two host life cycle involving salmonid fish a an aquatic oligochaete, Tubifex tubifex (Wolf, Markiw and Hiltunen, 1986). Whirling disease has been reported in 22 U.S. states with the greatest losses occurring in the salmonid fisheries...
Preliminary effects of water hardness on triactinomyxon production and development from eastern tubifex worms infected with Myxobolus cerebralis
Thomas B. Waldrop, Christine Densmore, Vicki Blazer, Dave Smith, Bane Schill
B. Schill, T. Waldrop, V. Blazer, editor(s)
1999, Book, 5th Annual Whirling Disease Symposium: Research and Management Perspectives
Whirling disease is caused by Myxobolus cerebralis and requires an intermediate oligochaete host identified as Tubifex tubifex (Wolf, Markiw, and Hiltunen, 1986). M. cerebralis spores ingested by the tubifex worms develop into triactinomyxons (tams) that are eventually released into the water column to infect salmonid fish. There may...
The effects of crude oil and remediation burning on three clones of smooth cordgrass (Spartina alterniflora loisel.)
D.L. Smith, C.E. Proffitt
1999, Estuaries (22) 616-623
Burning has been employed as an oil spill remediation technique in coastal marshes, even though the combined and interactive effects of oil and burning on vegetation are poorly understood. Variation among clones of perennial marsh grasses in response to these perturbations is not known. We performed a greenhouse experiment designed...
Petrology and geochemistry of late-stage intrusions of the A-type, mid-Proterozoic Pikes Peak batholith (Central Colorado, USA): Implications for petrogenetic models
D. R. Smith, J. Noblett, R. A. Wobus, D. Unruh, J. Douglass, R. Beane, C. Davis, S. Goldman, G. Kay, B. Gustavson, B. Saltoun, J. Stewart
1999, Precambrian Research (98) 271-305
The ~1.08 Ga anorogenic, A-type Pikes Peak batholith (Front Range, central Colorado) is dominated by coarse-grained, biotite ?? amphibole syenogranites and minor monzogranites, collectively referred to as Pikes Peak granite (PPG). The batholith is also host to numerous small, late-stage plutons that have been subdivided into two groups (e.g. Wobus,...