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Page 2297, results 57401 - 57425

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Not all publications have extents, not all extents are completely accurate
USGS assessment of undiscovered oil and gas resources in Paleogene strata of the U.S. Gulf of Mexico coastal plain and state waters
Peter D. Warwick, James L. Coleman, Paul C. Hackley, Daniel O. Hayba, Alexander W. Karlsen, Elisabeth L. Rowan, Sharon M. Swanson
Lorcan Kennan, James Pindell, Norman C. Rosen, editor(s)
2007, Conference Paper, The Paleogene of the Gulf of Mexico and Caribbean basins: Processes, events, and petroleum systems
This report presents a review of the U.S. Geological Survey (USGS) 2007 assessment of the undiscovered oil and gas resources in Paleogene strata underlying the U.S. Gulf of Mexico Coastal Plain and state waters. Geochemical, geologic, geophysical, thermal maturation, burial history, and paleontologic studies have been combined with regional cross...
Quasi-horizontal circulation cells in 3D seawater intrusion
E. Abarca, J. Carrera, X. Sanchez-Vila, Clifford I. Voss
2007, Journal of Hydrology (339) 118-129
The seawater intrusion process is characterized by the difference in freshwater and seawater density that causes freshwater to float on seawater. Many confined aquifers have a large horizontal extension with respect to thickness. In these cases, while buoyancy acts in the vertical direction, flow is confined between the upper and...
A simulation-based approach for estimating premining water quality: Red Mountain Creek, Colorado
Robert L. Runkel, Briant A Kimball, Katherine Walton-Day, Philip L. Verplanck
2007, Applied Geochemistry (22) 1899-1918
Regulatory agencies are often charged with the task of setting site-specific numeric water quality standards for impaired streams. This task is particularly difficult for streams draining highly mineralized watersheds with past mining activity. Baseline water quality data obtained prior to mining are often non-existent and application of generic water quality...
The instantaneous rate dependence in low temperature laboratory rock friction and rock deformation experiments
N.M. Beeler, T.E. Tullis, A. K. Kronenberg, L.A. Reinen
2007, Journal of Geophysical Research B: Solid Earth (112)
[1] Earthquake occurrence probabilities that account for stress transfer and time-dependent failure depend on the product of the effective normal stress and a lab-derived dimensionless coefficient a. This coefficient describes the instantaneous dependence of fault strength on deformation rate, and determines the duration of precursory slip....
Distinctiveness, use, and value of midwestern oak savannas and woodlands as avian habitats
R. Grundel, N.B. Pavlovic
2007, The Auk (124) 969-985
Oak savannas and woodlands historically covered millions of hectares in the midwestern United States but are rare today. We evaluated the ecological distinctiveness and conservation value of savannas and woodlands by examining bird distributions across a fire-maintained woody-vegetation gradient in northwest Indiana encompassing five habitats—open habitats with low canopy cover,...
Distribution of breeding shorebirds on the Arctic Coastal Plain of Alaska
James A. Johnson, Richard B. Lanctot, Brad A. Andres, Jonathan Bart, Stephen C. Brown, Steven J. Kendall, David C. Payer
2007, Arctic (60) 277-293
Available information on the distribution of breeding shorebirds across the Arctic Coastal Plain of Alaska is dated, fragmented, and limited in scope. Herein, we describe the distribution of 19 shorebird species from data gathered at 407 study plots between 1998 and 2004. This information was collected using a single-visit rapid...
Paleoearthquakes on the southern San Andreas Fault, Wrightwood, California, 3000 to 1500 B.C.: A new method for evaluating paleoseismic evidence and earthquake horizons
K.M. Scharer, R.J. Weldon II, T. E. Fumal, G. P. Biasi
2007, Bulletin of the Seismological Society of America (97) 1054-1093
We present evidence of 11–14 earthquakes that occurred between 3000 and 1500 b.c. on the San Andreas fault at the Wrightwood paleoseismic site. Earthquake evidence is presented in a novel form in which we rank (high, moderate, poor, or low) the quality of all...
A multidisciplinary study of the Lower Cretaceous Cedar Mountain Formation, Mussentuchit Wash, Utah: a determination of the paleoenvironment and paleoecology of the Eolambia caroljonesa dinosaur quarry
J.R. Garrison Jr., D. Brinkman, D. J. Nichols, P. Layer, D. Burge, D. Thayn
2007, Cretaceous Research (28) 461-494
A quarry within the Cedar Mountain Formation in Mussentuchit Wash, Emery County, Utah, produced a fossil assemblage containing the remains of at least eight juvenile iguanodontid dinosaurs (Eolambia caroljonesa). The Cedar Mountain Formation lies stratigraphically between the Tithonian-Berriasian (Upper Jurassic) Brushy Basin Member of the Morrison Formation and the Cenomanian...
Influence of fire on black-tailed prairie dog colony expansion in shortgrass steppe
D.J. Augustine, J.F. Cully Jr., T. L. Johnson
2007, Rangeland Ecology and Management (60) 538-542
Factors influencing the distribution and abundance of black-tailed prairie dog (Cynomys ludovicianus) colonies are of interest to rangeland managers because of the significant influence prairie dogs can exert on both livestock and biodiversity. We examined the influence of 4 prescribed burns and one wildfire on the rate and direction of...
Food web structure in exotic and native mangroves: A Hawaii-Puerto Rico comparison
A. W.J. Demopoulos, B. Fry, C. R. Smith
2007, Oecologia (153) 675-686
Plant invasions can fundamentally alter detrital inputs and the structure of detritus-based food webs. We examined the detrital pathways in mangrove food webs in native (Puerto Rican) and introduced (Hawaiian) Rhizophora mangle forests using a dual isotope approach and a mixing model. Based on trophic-level fractionation of 0-1??? for ??...
Numerical investigation of implementation of air-earth boundary by acoustic-elastic boundary approach
Y. Xu, J. Xia, R. D. Miller
2007, Geophysics (72)
The need for incorporating the traction-free condition at the air-earth boundary for finite-difference modeling of seismic wave propagation has been discussed widely. A new implementation has been developed for simulating elastic wave propagation in which the free-surface condition is replaced by an explicit acoustic-elastic boundary. Detailed comparisons of seismograms with...
Diverse dinosaur-dominated ichnofaunas from the Potomac Group (Lower Cretaceous) Maryland
Ray Stanford, Martin G. Lockley, Robert E. Weems
2007, Ichnos: An International Journal for Plant and Animal Traces (14) 155-173
Until recently fossil footprints were virtually unknown from the Cretaceous of the eastern United States. The discovery of about 300 footprints in iron-rich siliciclastic facies of the Patuxent Formation (Potomac Group) of Aptian age is undoubtedly one of the most significant Early Cretaceous track discoveries since the Paluxy track discoveries...
An outbreak of type C botulism in Herring Gulls (Larus argentatus) in Southeastern Sweden
A. Neimanis, D. Gavier-Widen, F. Leighton, T. Bollinger, Tonie E. Rocke, T. Morner
2007, Journal of Wildlife Diseases (43) 327-336
From 2000 to 2004, over 10,000 seabirds, primarily Herring Gulls (Larus argentatus), died from an undetermined cause in the Blekinge archipelago in southeastern Sweden. In June 2004, 24 affected Herring Gulls were examined clinically, killed humanely, and 23 were examined by necropsy. Seven and 10 unaffected Herring Gulls collected from...
Testing alternative ground water models using cross-validation and other methods
L. Foglia, S.W. Mehl, M. C. Hill, P. Perona, P. Burlando
2007, Ground Water (45) 627-641
Many methods can be used to test alternative ground water models. Of concern in this work are methods able to (1) rank alternative models (also called model discrimination) and (2) identify observations important to parameter estimates and predictions (equivalent to the purpose served by some types of sensitivity analysis). Some...
A genetic assessment of the recovery units for the mojave population of the desert tortoise, Gopherus agassizii
R. W. Murphy, K.H. Berry, T. Edwards, A.M. McLuckie
2007, Chelonian Conservation and Biology (6) 229-251
In the 1994 Recovery Plan for the Mojave population of the desert tortoise, Gopherus agassizii, the US Fish and Wildlife Service established 6 recovery units by using the best available data on habitat use, behavior, morphology, and genetics. To further assess the validity of the recovery units, we analyzed genetic...
Potential strategies for recovery of lake whitefish and lake herring stocks in eastern Lake Erie
K. Oldenburg, M.A. Stapanian, P.A. Ryan, E. Holm
2007, Journal of Great Lakes Research (33) 46-58
Lake Erie sustained large populations of ciscoes (Salmonidae: Coregoninae) 120 years ago. By the end of the 19th century, abundance of lake whitefish (Coregonus clupeaformis) had declined drastically. By 1925, the lake herring (a cisco) population (Coregonus artedii) had collapsed, although a limited lake herring fishery persisted in the eastern basin until...
Visible and near-infrared multispectral analysis of rocks at Meridiani Planum, Mars, by the Mars Exploration Rover Opportunity
W. H. Farrand, J.F. Bell III, J. R. Johnson, B.L. Jolliff, A.H. Knoll, S. M. McLennan, S. W. Squyres, W. M. Calvin, J.P. Grotzinger, R.V. Morris, J. Soderblom, S.D. Thompson, W.A. Watters, A. S. Yen
2007, Journal of Geophysical Research E: Planets (112)
Multispectral measurements in the visible and near infrared of rocks at Meridiani Planum by the Mars Exploration Rover Opportunity's Pancam are described. The Pancam multispectral data show that the outcrops of the Burns formation consist of two main spectral units which in stretched 673, 535, 432 nm color composites appear...
A classification of U.S. estuaries based on physical and hydrologic attributes
V.D. Engle, J.C. Kurtz, L.M. Smith, C. Chancy, P. Bourgeois
2007, Environmental Monitoring and Assessment (129) 397-412
A classification of U.S. estuaries is presented based on estuarine characteristics that have been identified as important for quantifying stressor-response relationships in coastal systems. Estuaries within a class have similar physical and hydrologic characteristics and would be expected to demonstrate similar biological responses to stressor loads from the adjacent watersheds....
Spectral element modelling of fault-plane reflections arising from fluid pressure distributions
M. Haney, R. Snieder, J.-P. Ampuero, R. Hofmann
2007, Geophysical Journal International (170) 933-951
The presence of fault-plane reflections in seismic images, besides indicating the locations of faults, offers a possible source of information on the properties of these poorly understood zones. To better understand the physical mechanism giving rise to fault-plane reflections in compacting sedimentary basins, we numerically model the full elastic wavefield...
Stress does not inhibit induced vitellogenesis in juvenile rainbow trout
A.R. Schwindt, G.W. Feist, C.B. Schreck
2007, Environmental Biology of Fishes (80) 453-463
Vitellogenin (Vtg) is a widely used biomarker for xenoestrogen exposure in male fishes. In female fishes Vtg can be negatively affected by stress independent of declines in estrogen. However, few data are available on the effect of stress in male fish abnormally producing Vtg, such as when exposed to xenoestrogens....
Habitat relationships of birds overwintering in a managed coastal prairie
H.Q. Baldwin, J.B. Grace, W.C. Barrow Jr., F.C. Rohwer
2007, Wilson Journal of Ornithology (119) 189-197
Grassland birds are considered to be rapidly declining in North America. Management approaches for grassland birds frequently rely on prescribed burning to maintain habitat in suitable condition. We evaluated the relationships among years since burn, vegetation structure, and overwintering grassland bird abundance in coastal prairie. Le Conte's Sparrows (Ammodramus leconteii)...
Effects of roads on habitat quality for bears in the southern Appalachians: A long-term study
M. J. Reynolds-Hogland, M.S. Mitchell
2007, Journal of Mammalogy (88) 1050-1061
We tested the hypothesis that gravel roads, not paved roads, had the largest negative effect on habitat quality for a population of American black bears (Ursus americanus) that lived in a protected area, where vehicle collision was a relatively minimal source of mortality. We also evaluated whether road use by...
Aqueous exposure to 4-nonylphenol and 17β-estradiol increases stress sensitivity and disrupts ion regulatory ability of juvenile atlantic salmon
Darrren T. Lerner, Bjorn Thrandur Bjornsson, Stephen D. McCormick
2007, Environmental Toxicology and Chemistry (26) 1433-1440
Population declines of wild Atlantic salmon have been attributed to an array of anthropogenic disturbances, including dams, commercial and recreational fishing, habitat loss, and pollution. Environmental contaminants in particular, can act as environmental stressors on fish, typically causing disruption of ion homeostasis due to their close association with the aquatic...