A kinematic model for the southern Alaska orocline based on regional fault patterns
Jonathan M.G. Glen
Aviva J. Sussman, Arlo B. Weil, editor(s)
2004, Book chapter, Orogenic curvature: Integrating paleomagnetic and structural analyses
Among the most prominent physiographic features of southern Alaska are a series of nested arcuate lineations, including the Denali fault, that parallel the concave-southward southern coastline of the state. These features are generally interpreted as major dextral shear zones that formed in the Late Cretaceous to early Tertiary in response...
Biomonitoring of Environmental Status and Trends (BEST) Program: Environmental contaminants and their effects on fish in the Columbia River Basin
Jo Ellen Hinck, Christopher J. Schmitt, Timothy M. Bartish, Nancy D. Denslow, Vicki Blazer, Patrick J. Anderson, James J. Coyle, Gail M. Dethloff, Donald E. Tillitt
2004, Scientific Investigations Report 2004-5154
This project examined and analyzed 560 fish representing eight species from 16 sites in the Columbia River Basin (CRB) from September 1997 to April 1998. Ten of the 16 sampling locations were historical National Contaminant Biomonitoring Program (NCBP) sites where organochlorine and elemental contaminants in fish had been monitored from...
The Colorado front range: anatomy of a Laramide uplift
Karl S. Kellogg, Bruce Bryant, John C. Reed
2004, Book chapter, GSA Field Guide
Along a transect across the Front Range from Denver to the Blue River valley near Dillon, the trip explores the geologic framework and Laramide (Late Cretaceous to early Eocene) uplift history of this basement-cored mountain range. Specific items for discussion at various stops are (1) the sedimentary and structural record...
Structure of the Red Dog District, western Brooks Range, Alaska
Jean-Pierre P. de Vera, K. R. McClay
2004, Economic Geology (99) 1415-1434
The Red Dog district of the western Brooks Range of northern Alaska, which includes the sediment-hosted Zn-Pb-Ag ± Ba deposits at Red Dog, Su-Lik, and Anarraaq, contains one of the world's largest reserves of zinc. This paper presents a new model for the structural development of the area and shows...
40Ar/39Ar Dating of Zn-Pb-Ag Mineralization in the Northern Brooks Range, Alaska
Melanie B. Werdon, Paul W. Layer, Rainer J. Newberry
2004, Economic Geology (99) 1323-1343
The 40Ar/39Ar laser step-heating method potentially can be used to provide absolute ages for a number of formerly undatable, low-temperature ore deposits. This study demonstrates the use of this method by determining absolute ages for Zn-Pb-Ag sediment-hosted massive sulfide deposits and vein-breccia occurrences found throughout a 300-km-long, east-west-trending belt in...
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. ...
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...
Geophysical data reveal the crustal structure of the Alaska Range orogen within the aftershock zone of the Mw 7.9 Denali fault earthquake
M. A. Fisher, N. A. Ratchkovski, W. J. Nokleberg, L. Pellerin, J.M.G. Glen
2004, Bulletin of the Seismological Society of America (94) S107-S131
Geophysical information, including deep-crustal seismic reflection, magnetotelluric (MT), gravity, and magnetic data, cross the aftershock zone of the 3 November 2002 Mw 7.9 Denali fault earthquake. These data and aftershock seismicity, jointly interpreted, reveal the crustal structure of the right-lateral-slip Denali fault and the eastern Alaska Range orogen, as well...
Annual Report for 2003 Wild Horse Research and Field Activities
Jason Ransom, Francis J. Singer, Linda Zeigenfuss
2004, Open-File Report 2004-1264
As stated in the Wild Horse Fertility Control Field Trial Plan, the Bureau of Land Management (BLM) has an immediate need for a safe, effective contraceptive agent to assist in the management of the large number of wild horses on western rangelands. The BLM and the U.S. Geological Survey-Biological Resources...
Burrowing mayflies as indicators of ecosystem health: Status of populations in two western Lake Superior embayments
Thomas A. Edsall, Owen T. Gorman, Lori M. Evrard
2004, Aquatic Ecosystem Health & Management (7) 507-513
The U.S. Environmental Protection Agency and Environment Canada are supporting the development of indicators of ecosystem health that can be used to report on progress in restoring and maintaining the Great Lakes ecosystem, as called for in the Great Lakes Water Quality Agreement between the United States and Canada. One...
Avian nest success in midwestern forests fragmented by agriculture
Melinda G. Knutson, Gerald J. Niemi, Wesley E. Newton, M. A. Friberg
2004, Condor (106) 116-130
We studied how forest-bird nest success varied by landscape context from 1996 to 1998 in an agricultural region of southeastern Minnesota, southwestern Wisconsin, and northeastern Iowa. Nest success was 48% for all nests, 82% for cavity-nesting species, and 42% for cup-nesting species. Mayfield-adjusted nest success for five common species ranged...
Sierra Nevada bioregion
J. W. van Wagtendonk, J. Fites-Kaufman
N. G. Sugihara, J. W. van Wagtendonk, J. Fites-Kaufman, K. E. Shaffer, A. E. Thode, editor(s)
2004, Book chapter, Fire in California ecosystems
This chapter addresses the immediately south of the Cascades in the Sierra Nevada bioregion, extending nearly half the length of the state of California. This bioregion is one of the most striking features of the state of California, extending from the southern Cascade Mountains in the north to the Tehachapi...
Deformation during terrane accretion in the Saint Elias orogen, Alaska
R.L. Bruhn, T.L. Pavlis, George Plafker, L. Serpa
2004, Geological Society of America Bulletin (116) 771-787
The Saint Elias orogen of southern Alaska and adjacent Canada is a complex belt of mountains formed by collision and accretion of the Yakutat terrane into the transition zone from transform faulting to subduction in the northeast Pacific. The orogen is an active analog for tectonic processes that formed much...
Radiated energy and the rupture process of the Denali fault earthquake sequence of 2002 from broadband teleseismic body waves
G. L. Choy, J. Boatwright
2004, Bulletin of the Seismological Society of America (94) S269-S277
Displacement, velocity, and velocity-squared records of P and SH body waves recorded at teleseismic distances are analyzed to determine the rupture characteristics of the Denali fault, Alaska, earthquake of 3 November 2002 (MW 7.9, Me 8.1). Three episodes of rupture can be identified from broadband (∼0.1–5.0 Hz) waveforms. The Denali fault earthquake started...
Differential consumption of eastern red cedar (Juniperus virginiana) by avian and mammalian guilds: Implications for tree invasion
V.J. Horncastle, E. C. Hellgren, P.M. Mayer, David M. Engle, D.M. Leslie
2004, American Midland Naturalist (152) 255-267
Increased abundance and distribution of eastern redcedar (Juniperns virginiannus), a native species in the Great Plains, has been associated with changes in ecosystem functioning and landscape cover. Knowledge of the main consumers and dispersal agents of eastern red cedar cones is essential to understanding the invasive spread of the species....
Divergence among barking frogs (Eleutherodactylus augusti) in the southwestern United States
Caren S. Goldberg, Brian K. Sullivan, John H. Malone, Cecil R. Schwalbe
2004, Herpetologica (60) 312-320
Barking frogs (Eleutherodactylus augusti) are distributed from southern Mexico along the Sierra Madre Occidental into Arizona and the Sierra Madre Oriental into Texas and New Mexico. Barking frogs in Arizona and most of Texas live in rocky areas in oak woodland, while those in New Mexico and far...
Petrography and character of the bedrock surface beneath western Cape Cod, Massachusetts
B.W. Hallett, L.J. Poppe, S.G. Brand
2004, Northeastern Geology and Environmental Sciences (26) 230-241
Cores collected during recent drilling in western Cape Cod, Massachusetts provide insight into the topography and petrology of the underlying bedrock. 62 drill sites spread over a ???140 km2 study area produced cores of granitoids (31), orthogneisses (20), basalts/diabases (4), amphibolites (3), felsic mylonites (2), and dolomitic rock (2). Granitoid...
An evaluation of the individual components and accuracies associated with the determination of impervious area
E.T. Slonecker, J.S. Tilley
2004, GIScience and Remote Sensing (41) 165-184
The percentage of impervious surface area in a watershed has been widely recognized as a key indicator of terrestrial and aquatic ecosystem condition. Although the use of the impervious indicator is widespread, there is currently no consistent or mutually accepted method of computing impervious area and the approach of various...
Vestiges of an Iapetan rift basin in the New Jersey Highlands: Implfications for the Neoproterozoic Laurentian margin
A.E. Gates, R.A. Volkert
2004, Journal of Geodynamics (37) 381-409
Thin, discontinuous remnants of Neoproterozoic intracratonic rift-basin deposits of the Chestnut Hill Formation occur in the western New Jersey Highlands. These deposits form an important link between well-documented Iapetan rift-basins in both the northern and southern Appalachians. The close spatial relations of Chestnut Hill rocks to Paleozoic sedimentary rocks open...
Atmospherically transported elements and deposition in the Southeastern United States: Local or transoceanic?
C. W. Holmes, R. Miller
2004, Conference Paper, Applied Geochemistry
Saharan dust is persistently transported and deposited in ecosystems of the western Atlantic Ocean. This dust is an aggregate of clay and quartz particles cemented with Fe oxides. Samples collected and analyzed from Mali (central Africa), the Azores, the Caribbean and the Eastern United States document the levels of minor...
Earthquake scenario and probabilistic ground-shaking hazard maps for the Albuquerque-Belen-Santa Fe, New Mexico, corridor
I. Wong, S. Olig, M. Dober, W. Silva, D. Wright, P. Thomas, N. Gregor, A. Sanford, K.-W. Lin, D. Love
2004, New Mexico Geology (26) 3-33
New Mexico's population is concentrated along the corridor that extends from Belen in the south to Española in the north and includes Albuquerque and Santa Fe. The Rio Grande rift, which encompasses the corridor, is a major tectonically, volcanically, and seismically active continental rift in the western U.S. Although only...
Reconstruction of the Upper Jurassic Morrison Formation extinct ecosystem - A synthesis
C.E. Turner, F. Peterson
2004, Sedimentary Geology (167) 309-355
A synthesis of recent and previous studies of the Morrison Formation and related beds, in the context of a conceptual climatic/hydrologic framework, permits reconstruction of the Late Jurassic dinosaurian ecosystem throughout the Western Interior of the United States and Canada. Climate models and geologic evidence indicate that a dry climate...
Mapping of the Culann-Tohil region of Io from Galileo imaging data
D.A. Williams, Paul M. Schenk, Jeffrey M. Moore, Laszlo P. Keszthelyi, Elizabeth P. Turtle, Windy L. Jaeger, Jani Radebaugh, Moses P. Milazzo, Rosaly Lopes, Ronald Greeley
2004, Icarus (169) 80-97
We have used Galileo spacecraft data to produce a geomorphologic map of the Culann–Tohil region of Io's antijovian hemisphere. This region includes a newly discovered shield volcano, Tsũi Goab Tholus and a neighboring bright flow field, Tsũi Goab Fluctus, the active Culann Patera and the enigmatic Tohil Mons-Radegast Patera–Tohil Patera complex. Analysis...
Interseismic strain and rotation rates in the northeast Mojave domain, eastern California
J.C. Savage, J. L. Svarc, II W. Prescott
2004, Journal of Geophysical Research B: Solid Earth (109)
The northeast Mojave domain, a type locality for bookshelf faulting, is a region of east striking, left-lateral faults in the northeast corner of the Mojave block, a block otherwise dominated by ∼N40°W striking, right-lateral faults. Paleomagnetic evidence suggests that blocks within the domain have rotated clockwise about a vertical axis...
Delineation of tectonic provinces of New York state as a component of seismic-hazard evaluation
R.H. Fakundiny
2004, Northeastern Geology and Environmental Sciences (26) 142-173
Seismic-hazard evaluations in the eastern United States must be based on interpretations of the composition and form of Proterozoic basement-rock terranes and overlying Paleozoic strata, and on factors that can cause relative movements among their units, rather than Phanerozoic orogenic structures, which may be independent of modern tectonics. The tectonic-province...
