Seismic history of the Middle America subduction zone along El Salvador, Guatemala, and Chiapas, Mexico: 1526–2000
Randall A. White, Juan Pablo Ligorria, I.L. Cifuentes
William I. Rose, Julian J. Bommer, Dina L. Lopez, Michael J. Carr, Jon J. Major, editor(s)
2004, Book chapter, Natural hazards in El Salvador
We present a catalog of subduction zone earthquakes along the Pacific coast from central El Salvador to eastern Chiapas, Mexico, from 1526 to 2000. We estimate that the catalog is complete since 1690 for MS ≥7.4 thrust events and M ≥ 7.4 normal-faulting events within the upper 60 km of the...
Porosity and pore-size distribution
John R. Nimmo
2004, Book chapter, Encyclopedia of soils in the environment
No abstract available. ...
Using geochemical data and aquifer simulation to characterize recharge and groundwater flow in the Middle Rio Grande Basin, New Mexico
Niel Plummer, Ward E. Sanford, Laura M. Bexfield, Scott K. Anderholm, Eurybiades Busenberg
James F. Hogan, Fred M. Phillips, Bridget R. Scanlon, editor(s)
2004, Book chapter, Groundwater recharge in a desert environment: The southwestern United States
No abstract available. ...
Selenium loading through the Blackfoot River watershed--linking sources to ecosystem
Theresa S. Presser, Matthew Hardy, Mark Huebner, Paul J. Lamothe
James R. Hein, editor(s)
2004, Book chapter, Handbook of exploration and environmental geochemistry
The upper Blackfoot River watershed in southeast Idaho receives drainage from 11 of 16 phosphate mines that have extracted ore from the Phosphoria Formation, three of which are presently active. Toxic effects from selenium (Se), including death of livestock and deformity in aquatic birds, were documented locally in areas...
Fundamental concepts of recharge in the Desert Southwest: A regional modeling perspective
Alan L. Flint, Lorraine E. Flint, J.A. Hevesi
2004, Book chapter, Groundwater recharge in a desert environment: The southwestern United States
Recharge in arid basins does not occur in all years or at all locations within a basin. In the desert Southwest potential evapotranspiration exceeds precipitation on an average annual basis and, in many basins, on an average monthly basis. Ground-water traveltime from the surface to the water table and recharge...
Seismicity and tectonics of El Salvador
James W. Dewey, Randall A. White, Douglas A. Hernandez
William I. Rose, Julian J. Bommer, Dina L. Lopez, Michael J. Carr, Jon J. Major, editor(s)
2004, Book chapter, Natural hazards in El Salvador
The large-scale plate-tectonics framework of El Salvador was defined in the “plate-tectonics revolution” of the 1960s and 1970s, but important issues related to seismic hazards depend on details that have been only recently, or are not yet, understood. Present evidence suggests that coupling across the interface-thrust zone beneath coastal El...
Age and evolution of the Precambrian crust of the Tobacco Root Mountains, Montana
Paul A. Mueller, Henry Robert Burger, Joseph L. Wooden, Ann L. Heatherington, David W. Mogk, Kimberly D’Arcy
John B. Brady, John T. Cheney, Tekla Harms, editor(s)
2004, Book chapter, Precambrian geology of the Tobacco Root Mountains, Montana
U-Pb analyses of zircons from gneisses, anatectic leucosome, metasedimentary rocks, and a younger (metamorphosed) mafic dike from the Tobacco Root Mountains of southwestern Montana document a Precambrian history that extends from at least 3.90–1.77 Ga. The oldest U-Pb age reported here (3.8 Ga) is from a detrital zircon from a...
Geochemistry of quartzofeldspathic gneisses and metamorphic mafic rocks of the Indian Creek and Pony–Middle Mountain Metamorphic Suites, Tobacco Root Mountains, Montana
David W. Mogk, Henry Robert Burger, Paul A. Mueller, Kimberly D’Arcy, Ann L. Heatherington, Joseph L. Wooden, Reyna L. Abeyta, Jennifer L. Martin, Lisa J. Jacob
John B. Brady, John T. Cheney, Tekla Harms, editor(s)
2004, Book chapter, Precambrian geology of the Tobacco Root Mountains, Montana
Quartzofeldspathic gneisses and metamorphic mafic rocks are the dominant lithologies in the Indian Creek and Pony–Middle Mountain Metamorphic Suites of the Tobacco Root Mountains. Field relations, geochemical discriminant analysis, and isotopic systematics indicate that these rocks derive from a bimodal volcanic suite ca. 3.3 Ga. The quartzofeldspathic gneisses contain sodic...
Oak-black bear relationships in southeastern uplands
Joseph D. Clark
Martin A. Spetich, editor(s)
2004, Report, Upland oak ecology symposium: history, current conditions, and sustainability
Bears (Ursus americanus) primarily occur in upland habitats in the Southeast because uplands were the last to be developed for agriculture and were more likely to become publicly owned. National parks and forests created in the early to mid-1900s served as sources to supply surrounding uplands with bears. Bears could...
Ground-nesting marine birds and potential for human disturbance in Glacier Bay National Park
Mayumi L. Arimitsu, Marc D. Romano, John F. Piatt
John F. Piatt, S.M. Gende, editor(s)
2004, Conference Paper, Proceedings of the Fourth Glacier Bay Science Symposium
Glacier Bay National Park and Preserve contains a diverse assemblage of marine birds that use the area for nesting, foraging and molting. The abundance and diversity of marine bird species in Glacier Bay is unmatched in the region, due in part to the geomorphic and successional characteristics that result in...
Designing monitoring programs in an adaptive management context for regional multiple species conservation plans
A.J. Atkinson, P.C. Trenham, Robert N. Fisher, S.A. Hathaway, B.S. Johnson, S.G. Torres, Y.C. Moore
2004, Report
Increasing numbers of regional, multiple species conservation plans have been developed in California since the early 1990s. However, building effective monitoring and adaptive management programs to support these plans has remained a challenge. In addition to collecting data on the status of resources and the results of management actions, monitoring...
Differential spring migration by male and female Western Sandpipers at interior and coastal stopover sites
Mary Anne Bishop, Nils Warnock, John Y. Takekawa
2004, Ardea (92) 185-196
Western Sandpipers Calidris mauri are differential migrants on their non-breeding areas, with females wintering farther south. Earlier passage of males in the spring has been explained by sexual differences in winter latitude (male-biased sex ratios at more northerly areas) and onset of migration (males departing earlier). We investigated sex differences...
Gray wolves in and adjacent to Voyageurs National Park, Minnesota: Research and synthesis 1987-1991
P.J.P. Gogan, W.T. Route, E.M. Olexa, N. Thomas, D. Kuehn, K.M. Podruzny
2004, Technical Report NPS/MWR/NRTR/2004-01
No abstract available....
Mineral resource of the month: molybdenum
Michael J. Magyar
2004, Geotimes (2004)
Molybdenum is a metallic element that is most frequently used in alloy and stainless steels, which together represent the single largest market for molybdenum. Molybdenum has also proven invaluable in carbon steel, cast iron and superalloys. Its alloying versatility is unmatched because its addition enhances material performance under high-stress conditions...
Limnological and climatic environments at Upper Klamath Lake, Oregon during the past 45 000 years
J.P. Bradbury, Steven M. Colman, W.E. Dean
2004, Journal of Paleolimnology (31) 167-188
Upper Klamath Lake, in south-central Oregon, contains long sediment records with well-preserved diatoms and lithological variations that reflect climate-induced limnological changes. These sediment archives complement and extend high resolution terrestrial records along a north-south transect that includes areas influenced by the Aleutian Low and Subtropical High, which control both marine...
Duration of the Arctic sea ice melt season: Regional and interannual variability, 1979-2001
G. I. Belchansky, David C. Douglas, Nikita G. Platonov
2004, Journal of Climate (17) 67-80
Melt onset dates, freeze onset dates, and melt season duration were estimated over Arctic sea ice, 1979–2001, using passive microwave satellite imagery and surface air temperature data. Sea ice melt duration for the entire Northern Hemisphere varied from a 104-day minimum in 1983 and 1996 to a 124-day maximum in...
Using satellite radiotelemetry data to delineate and manage wildlife populations
Steven C. Amstrup, T. L. McDonald, George M. Durner
2004, Wildlife Society Bulletin (32) 661-679
The greatest promise of radiotelemetry always has been a better understanding of animal movements. Telemetry has helped us know when animals are active, how active they are, how far and how fast they move, the geographic areas they occupy, and whether individuals vary in these traits. Unfortunately, the inability to...
Foraging depths of sea otters and implications to coastal marine communities
James L. Bodkin, George G. Esslinger, Daniel H. Monson
2004, Marine Mammal Science (20) 305-321
We visually observed 1,251 dives, of 14 sea otters instrumented with TDRs in southeast Alaska, and used attribute values from observed dives to classify 180,848 recorded dives as foraging (0.64), or traveling (0.36). Foraging dives were significantly deeper, with longer durations, bottom times, and postdive surface intervals, and greater descent...
A quantitative approach to identifying predators from nest remains
R. Michael Anthony, J.B. Grand, T.F. Fondell, B.F. Manly
2004, Journal of Field Ornithology (75) 40-48
Nesting success of Dusky Canada Geese (Branta canadensis occidentalis) has declined greatly since a major earthquake affected southern Alaska in 1964. To identify nest predators, we collected predation data at goose nests and photographs of predators at natural nests containing artificial eggs in 1997-2000. To document feeding behavior by nest...
Mineral resource of the month: tantalum
Larry D. Cunningham
2004, Geotimes (2004)
Tantalum is a metal that is critical to the United States because of its defense-related applications in aircraft, missiles and radio communications. It is ductile, easily fabricated, highly resistant to corrosion by acids, a good conductor of heat and electricity, and has a high melting point. Tantalum’s first commercial usage...
Mineral resource of the month: lead
David Guberman
2004, Geotimes (2004)
The United States is a major producer and consumer of refined lead, representing almost one quarter of total world production and consumption. Two mines in Alaska and six in Missouri accounted for 97 percent of domestic lead production in 2002. The United States also imports enough refined lead to satisfy...
Use and interpretation of logistic regression in habitat-selection studies
Kim A. Keating, Steve Cherry
2004, Journal of Wildlife Management (68) 774-789
Logistic regression is an important tool for wildlife habitat-selection studies, but the method frequently has been misapplied due to an inadequate understanding of the logistic model, its interpretation, and the influence of sampling design. To promote better use of this method, we review its application and interpretation under 3...
Possible effects of elk harvest on fall distribution of grizzly bears in the Greater Yellowstone Ecosystem
M.A. Haroldson, C.C. Schwartz, S. Cherry, D. Moody
2004, Journal of Wildlife Management (68) 129-137
The tradition of early elk (Cervus elaphus) hunting seasons adjacent to Yellowstone National Park (YNP), USA, provides grizzly bears (Ursus arctos horribilis) with ungulate remains left by hunters. We investigated the fall (Aug–Oct) distribution of grizzly bears relative to the boundaries of YNP and the opening of September elk hunting...
Grizzly bear-human conflicts in the Yellowstone ecosystem, 1992-2000
K.A. Gunther, M.A. Haroldson, S.L. Cain, J. Copeland, K. Frey, C.C. Schwartz
2004, Ursus (15) 10-22
For many years, the primary strategy for managing grizzly bears (Ursus arctos) that came into conflict with humans in the Greater Yellowstone Ecosystem (GYE) was to capture and translocate the offending bears away from conflict sites. Translocation usually only temporarily alleviated the problems and most often did not result in...
Manatees as sentinels of marine ecosystem health: are they the 2000-pound canaries?
R. K. Bonde, A.A. Aguirre, J. Powell
2004, EcoHealth (1) 255-262
The order Sirenia is represented by three species of manatees and one species of dugong distributed in tropical and subtropical regions of the world and considered vulnerable to extinction. The sentinel species concept is useful to identify indicators of the environment and may reflect the quality of health in marine...
