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Page 1797, results 44901 - 44925

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Late Holocene slip rate of the San Andreas fault and its accommodation by creep and moderate-magnitude earthquakes at Parkfield, California
N.A. Toke, J.R. Arrowsmith, Michael J. Rymer, A. Landgraf, D.E. Haddad, M. Busch, J. Coyan, A. Hannah
2011, Geology (39) 243-246
Investigation of a right-laterally offset channel at the Miller's Field paleoseismic site yields a late Holocene slip rate of 26.2 +6.4/−4.3 mm/yr (1σ) for the main trace of the San Andreas fault at Parkfield, California. This is the first well-documented geologic slip rate between the Carrizo and creeping sections of...
Quantifying Uncertainty in Model Predictions for the Pliocene (Plio-QUMP): Initial results
J.O. Pope, M. Collins, A.M. Haywood, Harry J. Dowsett, S.J. Hunter, D.J. Lunt, S.J. Pickering, M.J. Pound
2011, Palaeogeography, Palaeoclimatology, Palaeoecology (309) 128-140
Examination of the mid-Pliocene Warm Period (mPWP; ~ 3.3 to 3.0 Ma BP) provides an excellent opportunity to test the ability of climate models to reproduce warm climate states, thereby assessing our confidence in model predictions. To do this it is necessary to relate the uncertainty in model simulations of mPWP...
Gently dipping normal faults identified with Space Shuttle radar topography data in central Sulawesi, Indonesia, and some implications for fault mechanics
J.E. Spencer
2011, Earth and Planetary Science Letters (308) 267-276
Space-shuttle radar topography data from central Sulawesi, Indonesia, reveal two corrugated, domal landforms, covering hundreds to thousands of square kilometers, that are bounded to the north by an abrupt transition to typical hilly to mountainous topography. These domal landforms are readily interpreted as metamorphic core complexes, an interpretation consistent with a...
Mapping the distribution of materials in hyperspectral data using the USGS Material Identification and Characterization Algorithm (MICA)
Raymond F. Kokaly, T. V. V. King, Todd M. Hoefen
2011, Conference Paper, International Geoscience and Remote Sensing Symposium (IGARSS)
Identifying materials by measuring and analyzing their reflectance spectra has been an important method in analytical chemistry for decades. Airborne and space-based imaging spectrometers allow scientists to detect materials and map their distributions across the landscape. With new satellite-borne hyperspectral sensors planned for the future, for example, HYSPIRI (HYPerspectral InfraRed...
The application of prototype point processes for the summary and description of California wildfires
K. Nichols, F.P. Schoenberg, Jon E. Keeley, A. Bray, D. Diez
2011, Journal of Time Series Analysis (32) 420-429
A method for summarizing repeated realizations of a space‐time marked point process, known as prototyping, is discussed and applied to catalogues of wildfires in California. Prototype summaries are constructed for varying time intervals using California wildfire data from 1990 to 2006. Previous work on prototypes for temporal and space‐time point...
Evidence of segregated spawning in a single marine fish stock: Sympatric divergence of ecotypes in icelandic cod?
T.B. Grabowski, Vilhjalmur Thorsteinsson, B.J. McAdam, G. Marteinsdottir
2011, PLoS ONE (6)
There is increasing recognition of intraspecific diversity and population structure within marine fish species, yet there is little direct evidence of the isolating mechanisms that maintain it or documentation of its ecological extent. We analyzed depth and temperature histories collected by electronic data storage tags retrieved from 104 Atlantic cod...
Evaluation of a black-footed ferret resource utilization function model
D.A. Eads, J.J. Millspaugh, Dean E. Biggins, D.S. Jachowski, T.M. Livieri
2011, Journal of Wildlife Management (75) 1155-1163
Resource utilization function (RUF) models permit evaluation of potential habitat for endangered species; ideally such models should be evaluated before use in management decision‐making. We evaluated the predictive capabilities of a previously developed black‐footed ferret (Mustela nigripes) RUF. Using the population‐level RUF, generated from ferret observations at an adjacent yet...
Constraints on the long-period moment-dip tradeoff for the Tohoku earthquake
V.C. Tsai, Gavin P. Hayes, Z. Duputel
2011, Geophysical Research Letters (38)
Since the work of Kanamori and Given (1981), it has been recognized that shallow, pure dip‐slip earthquakes excite long‐period surface waves such that it is difficult to independently constrain the moment (M0) and the dip (δ) of the source mechanism, with only the product M0 sin(2δ) being well constrained. Because of this,...
Diagnostic methodology is critical for accurately determining the prevalence of ichthyophonus infections in wild fish populations
R. Kocan, H. Dolan, P. Hershberger
2011, Journal of Parasitology (97) 344-348
Several different techniques have been employed to detect and identify Ichthyophonus spp. in infected fish hosts; these include macroscopic observation, microscopic examination of tissue squashes, histological evaluation, in vitro culture, and molecular techniques. Examination of the peer-reviewed literature revealed that when more than 1 diagnostic method is used, they often...
Neoproterozoic extension in the greater dharwar craton: A reevaluation of the "betsimisaraka suture" in madagascar
R. D. Tucker, J.-Y. Roig, C. Delor, Y. Amlin, P. Goncalves, M.H. Rabarimanana, A.V. Ralison, R.W. Belcher
2011, Canadian Journal of Earth Sciences (48) 389-417
The Precambrian shield of Madagascar is reevaluated with recently compiled geological data and new U-Pb sensitive high-resolution ion microprobe (SHRIMP) geochronology. Two Archean domains are recognized: the eastern Antongil-Masora domain and the central Antananarivo domain, the latter with distinctive belts of metamafic gneiss and schist (Tsaratanana Complex). In the eastern...
Feasibility of waveform inversion of Rayleigh waves for shallow shear-wave velocity using a genetic algorithm
C. Zeng, J. Xia, R. D. Miller, G.P. Tsoflias
2011, Journal of Applied Geophysics (75) 648-655
Conventional surface wave inversion for shallow shear (S)-wave velocity relies on the generation of dispersion curves of Rayleigh waves. This constrains the method to only laterally homogeneous (or very smooth laterally heterogeneous) earth models. Waveform inversion directly fits waveforms on seismograms, hence, does not have such a limitation. Waveforms of...
Active aeolian processes on Mars: A regional study in Arabia and Meridiani Terrae
S. Silvestro, D.A. Vaz, L.K. Fenton, Paul E. Geissler
2011, Geophysical Research Letters (38)
We present evidence of widespread aeolian activity in the Arabia Terra/Meridiani region (Mars), where different kinds of aeolian modifications have been detected and classified. Passing from the regional to the local scale, we describe one particular dune field in Meridiani Planum, where two ripple populations are distinguished by means of...
Allelopathic cover crop prior to seeding is more important than subsequent grazing/mowing in Grassland establishment
D.G. Milchunas, Mark W. Vandever, L.O. Ball, S. Hyberg
2011, Rangeland Ecology and Management (64) 291-300
The effects of grazing, mowing, and type of cover crop were evaluated in a previous winter wheat–fallow cropland seeded to grassland under the Conservation Reserve Program in eastern Colorado. Prior to seeding, the fallow strips were planted to forage sorghum or wheat in alternating strips (cover crops), with no grazing, moderate to...
Thorium abundances of basalt ponds in South Pole-Aitken basin: Insights into the composition and evolution of the far side lunar mantle
Justin Hagerty, D. J. Lawrence, B. R. Hawke
2011, Journal of Geophysical Research E: Planets (116) 1-23
Imbrian-aged basalt ponds, located on the floor of South Pole-Aitken (SPA) basin, are used to provide constraints on the composition and evolution of the far side lunar mantle. We use forward modeling of the Lunar Prospector Gamma Ray Spectrometer thorium data, to suggest that at least five different and distinct...
New optically stimulated luminescence ages provide evidence of MIS3 and MIS2 eolian activity on Black Mesa, northeastern Arizona, USA
A.L. Ellwein, Shannon A. Mahan, L. D. McFadden
2011, Quaternary Research (75) 395-398
Eolian deposition on the semiarid southern Colorado Plateau has been attributed to episodic aridity during the Quaternary Period. However, OSL ages from three topographically controlled (e.g. falling) dunes on Black Mesa in northeastern Arizona indicate that eolian sediments there were deposited in deep tributary valleys as early as 35–30 ka,...
The distance that contaminated aquatic subsidies extend into lake riparian zones
D.F. Raikow, D.M. Walters, K.M. Fritz, M.A. Mills
2011, Ecological Applications (21) 983-990
Consumption of emergent aquatic insects by terrestrial invertebrates is a poorly resolved, but potentially important, mechanism of contaminant flux across ecosystem borders leading to contaminant exposure in terrestrial invertivores. We characterized the spatial extent and magnitude of contaminant transfer from aquatic sediments to terrestrial invertebrate predators by examining riparian araneid...
Ungulate herbivory on alpine willow in the Sangre de Cristo Mountains of Colorado
Linda Zeigenfuss, Kathryn A. Schoenecker, L.K.V. Amburg
2011, Western North American Naturalist (71) 86-96
In many areas of the Rocky Mountains, elk (Cervus elaphus) migrate from low-elevation mountain valleys during spring to high-elevation subalpine and alpine areas for the summer. Research has focused on the impacts of elk herbivory on winter-range plant communities, particularly on woody species such as willow and aspen; however, little...
San Andreas fault earthquake chronology and Lake Cahuilla history at Coachella, California
B. Philibosian, T. Fumal, R. Weldon
2011, Bulletin of the Seismological Society of America (101) 13-38
The southernmost ~100 km of the San Andreas fault has not ruptured historically. It is imperative to determine its rupture history to better predict its future behavior. This paleoseismic investigation in Coachella, California, establishes a chronology of at least five and up to seven major earthquakes during the past ~1100...
A novel approach for direct estimation of fresh groundwater discharge to an estuary
Neil K. Ganju
2011, Geophysical Research Letters (38)
Coastal groundwater discharge is an important source of freshwater and nutrients to coastal and estuarine systems. Directly quantifying the spatially integrated discharge of fresh groundwater over a coastline is difficult due to spatial variability and limited observational methods. In this study, I applied a novel approach to estimate net freshwater...
Coal resources for the Chemard Lake (Naborton No. 2) coal zone of the lower Wilcox group (Paleocene), northwestern Louisiana
Peter D. Warwick, Steven M. Podwysocki, Adam C. Schultz
Peter D. Warwick, Alexander K. Karlsen, Matthew D. Merrill, Brett J. Valentine, editor(s)
2011, Book chapter, Geologic assessment of coal in the Gulf of Mexico coastal plain
The lower part of the Wilcox Group of northwest Louisiana contains shallow (less than 500 ft) coal deposits that are mined for use in mine-mouth electric power-generating plants. The coal deposits, which are lignite A in apparent rank (Pierce et al., 2011), occur on the eastern part of the Sabine...
Fire management of Mediterranean landscapes
Jon E. Keeley, William J. Bond, Ross A. Bradstock, Juli G. Pausas, Philip W. Rundel
2011, Book chapter, Fire in Mediterranean ecosystems: Ecology, evolution and management
The hazardous mediterranean climate, highly flammable vegetation, and rugged terrain, all important elements of fire behavior, become problems only in the presence of people. People recreate and build homes in the mediterranean wildlands because of the delightful climate and will continue to do so as long as space is...
Comparisons of watershed sulfur budgets in southeast Canada and northeast US: New approaches and implications
Myron J. Mitchell, Gary Lovett, Scott Bailey, Fred Beall, Doug Burns, Don Buso, Thomas A. Clair, Francois Courchesne, Louis Duchesne, Cathy Eimers, Ivan Fernandez, Daniel Houle, Dean S. Jeffries, Gene E. Likens, Michael D. Moran, Christopher Rogers, Donna Schwede, Jamie Shanley, Kathleen C. Weathers, Robert Vet
2011, Biogeochemistry (103) 181-207
Most of eastern North America receives elevated levels of atmospheric deposition of sulfur (S) that result from anthropogenic SO2 emissions from fossil fuel combustion. Atmospheric S deposition has acidified sensitive terrestrial and aquatic ecosystems in this region; however, deposition has been declining since the 1970s, resulting in some recovery in previously...
Eocene bituminous coal deposits of the Claiborne group, Webb County, Texas
Robert W. Hook, Peter D. Warwick
Peter D. Warwick, Alexander K. Karlsen, Matthew D. Merrill, Brett J. Valentine, editor(s)
2011, Book chapter, Geologic assessment of coal in the Gulf of Mexico coastal plain
Two bituminous coal zones, the San Pedro and the Santo Tomas, in the middle Eocene Claiborne Group of Webb County, south Texas (Figure 1), are among the coal resources that are not evaluated quantitatively as part of the current Gulf Coastal Plain coal resource assessment. Coal beds within these zones...
Upper Cretaceous bituminous coal deposits of the Olmos Formation, Maverick County, Texas
Robert W. Hook, Peter D. Warwick, John R. SanFilipo
Peter D. Warwick, Alexander K. Karlsen, Matthew D. Merrill, Brett J. Valentine, editor(s)
2011, Book chapter, Geologic assessment of coal in the Gulf of Mexico coastal plain
This report describes the bituminous coal deposits of the Olmos Formation (Navarro Group, Upper Cretaceous; Figures 1, 2) of Maverick County in south Texas. Although these were not evaluated quantitatively as part of the current Gulf Coastal Plain coal-resource assessment, a detailed review is presented in this chapter.Prior to the...