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Page 194, results 4826 - 4850

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Not all publications have extents, not all extents are completely accurate
The flow dynamics of an extremely large volume pyroclastic flow, the 2.08-Ma Cerro Galán Ignimbrite, NW Argentina, and comparison with other flow types
Ray A.F. Cas, Heather M. Wright, Christopher B. Folkes, Chiara Lesti, Massimiliano Porreca, Guido Giordano, Jose G. Viramonte
2011, Bulletin of Volcanology (73) 1583-1609
The 2.08-Ma Cerro Galán Ignimbrite (CGI) represents a >630-km3 dense rock equivalent (VEI 8) eruption from the long-lived Cerro Galán magma system (∼6 Ma). It is a crystal-rich (35–60%), pumice (<10% generally) and lithic-poor (<5% generally) rhyodacitic ignimbrite, lacking a preceding plinian fallout deposit. The CGI is preserved up to 80 km...
Pseudospectral modeling and dispersion analysis of Rayleigh waves in viscoelastic media
K. Zhang, Y. Luo, J. Xia, C. Chen
2011, Soil Dynamics and Earthquake Engineering (31) 1332-1337
Multichannel Analysis of Surface Waves (MASW) is one of the most widely used techniques in environmental and engineering geophysics to determine shear-wave velocities and dynamic properties, which is based on the elastic layered system theory. Wave propagation in the Earth, however, has been recognized as viscoelastic and the propagation of...
Soil carbon sequestration potential for "grain for green" project in Loess Plateau, China
R. Chang, B. Fu, Gaisheng Liu, S. Liu
2011, Environmental Management (48) 1158-1172
Conversion of cropland into perennial vegetation land can increase soil organic carbon (SOC) accumulation, which might be an important mitigation measure to sequester carbon dioxide from the atmosphere. The “Grain for Green” project, one of the most ambitious ecological programmes launched in modern China, aims at transforming the low-yield slope...
Tracking solutes and water from subsurface drip irrigation application of coalbed methane-produced waters, Powder River Basin, Wyoming
Mark A. Engle, Carleton R. Bern, Richard W. Healy, J.I. Sams, J.W. Zupancic, K.T. Schroeder
2011, Environmental Geosciences (18) 169-187
One method to beneficially use water produced from coalbed methane (CBM) extraction is subsurface drip irrigation (SDI) of croplands. In SDI systems, treated CBM water (injectate) is supplied to the soil at depth, with the purpose of preventing the buildup of detrimental salts near the surface. The technology is...
Provenance of Des Moines lobe till records ice-stream catchment evolution during Laurentide deglaciation
B.A. Lusardi, C.E. Jennings, K.L. Harris
2011, Boreas (40) 585-597
Mapping and analysis of deposits of the Des Moines lobe of the Laurentide Ice Sheet, active after the Last Glacial Maximum (LGM), reveal several texturally and lithologically distinct tills within what had been considered to be a homogeneous deposit. Although the differences between tills are subtle, minor distinctions are predictable...
Perceptions of strengths and deficiencies: Disconnects between graduate students and prospective employers
M.D. Sundberg, P. Deangelis, K. Havens, K. Holsinger, K. Kennedy, A.T. Kramer, R. Muir, Peggy Olwell, K. Schierenbeck, L. Stritch, B. Zorn-Arnold
2011, BioScience (61) 133-138
The US Botanical Capacity Assessment Project (BCAP) was initiated as a first step to gauge the nation's collective ability to meet the environmental challenges of the 21st century. The project, in which the authors of this article are involved, specifically aimed to identify multisector contributions to and gaps in botanical...
Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts
T. Liebich, S. D. McCormick, D. Kircheis, Kevin Johnson, R. Regal, T. Hrabik
2011, Journal of Fish Biology (79) 502-519
The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream‐water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose,...
Modeling routes of chronic wasting disease transmission: Environmental prion persistence promotes deer population decline and extinction
Emily S. Almberg, Paul C. Cross, Christopher J. Johnson, Dennis M. Heisey, Bryan J. Richards
2011, PLoS ONE (6)
Chronic wasting disease (CWD) is a fatal disease of deer, elk, and moose transmitted through direct, animal-to-animal contact, and indirectly, via environmental contamination. Considerable attention has been paid to modeling direct transmission, but despite the fact that CWD prions can remain infectious in the environment for years, relatively little information...
Continuity of Landsat observations: Short term considerations
Michael A. Wulder, Joanne C. White, Jeffery G. Masek, John L. Dwyer, David P. Roy
2011, Remote Sensing of Environment (115) 747-751
As of writing in mid-2010, both Landsat-5 and -7 continue to function, with sufficient fuel to enable data collection until the launch of the Landsat Data Continuity Mission (LDCM) scheduled for December of 2012. Failure of one or both of Landsat-5 or -7 may result in a lack of Landsat...
Stratigraphy and chronology of offshore to nearshore deposits associated with the Provo shoreline, Pleistocene Lake Bonneville, Utah
H.S. Godsey, Charles G. Oviatt, D. M. Miller, M.A. Chan
2011, Palaeogeography, Palaeoclimatology, Palaeoecology (310) 442-450
Stratigraphic descriptions and radiocarbon data from eleven field locations are presented in this paper to establish a chronostratigraphic framework for offshore to nearshore deposits of Lake Bonneville. Based on key marker beds and geomorphic position, the deposits are interpreted to have accumulated during the period from the late transgressive phase,...
An analysis of modern pollen rain from the Maya lowlands of northern Belize
T. Bhattacharya, T. Beach, David B. Wahl
2011, Review of Palaeobotany and Palynology (164) 109-120
In the lowland Maya area, pollen records provide important insights into the impact of past human populations and climate change on tropical ecosystems. Despite a long history of regional paleoecological research, few studies have characterized the palynological signatures of lowland ecosystems, a fact which lowers confidence in ecological inferences made...
Nutrient loadings to streams of the Continental United States from municipal and industrial effluent
M.A. Maupin, T. Ivahnenko
2011, Journal of the American Water Resources Association (47) 950-964
Data from the United States Environmental Protection Agency Permit Compliance System national database were used to calculate annual total nitrogen (TN) and total phosphorus (TP) loads to surface waters from municipal and industrial facilities in six major regions of the United States for 1992, 1997, and 2002. Concentration and effluent...
Hillslope chemical weathering across Paraná, Brazil: a data mining-GIS hybrid approach
Fabio Iwashita, Michael J. Friedel, Carlos Roberto de Souza Filho, Stephen J. Fraser
2011, Geomorphology (132) 167-175
Self-organizing map (SOM) and geographic information system (GIS) models were used to investigate the nonlinear relationships associated with geochemical weathering processes at local (~100 km2) and regional (~50,000 km2) scales. The data set consisted of 1) 22 B-horizon soil variables: P, C, pH, Al, total acidity, Ca, Mg, K, total cation exchange...
Mountain treelines: A roadmap for research orientation
George P. Malanson, Lynn M. Resler, Maaike Y. Bader, Fredrich-Karl Holtmeier, David R. Butler, Daniel J. Weiss, Lori D. Daniels, Daniel B. Fagre
2011, Arctic, Antarctic, and Alpine Research (43) 167-177
For over 100 years, mountain treelines have been the subject of varied research endeavors and remain a strong area of investigation. The purpose of this paper is to examine aspects of the epistemology of mountain treeline research-that is, to investigate how knowledge on treelines has been acquired and the changes...
Lagrangian mass-flow investigations of inorganic contaminants in wastewater-impacted streams
L. B. Barber, Ronald C. Antweiler, J.L. Flynn, S.H. Keefe, D.W. Kolpin, D.A. Roth, D.J. Schnoebelen, Howard E. Taylor, P. L. Verplanck
2011, Environmental Science & Technology (45) 2575-2583
Understanding the potential effects of increased reliance on wastewater treatment plant (WWTP) effluents to meet municipal, agricultural, and environmental flow requires an understanding of the complex chemical loading characteristics of the WWTPs and the assimilative capacity of receiving waters. Stream ecosystem effects are linked to proportions of WWTP effluent under...
Epistemic uncertainty in California-wide synthetic seismicity simulations
F. F. Pollitz
2011, Bulletin of the Seismological Society of America (101) 2481-2498
The generation of seismicity catalogs on synthetic fault networks holds the promise of providing key inputs into probabilistic seismic-hazard analysis, for example, the coefficient of variation, mean recurrence time as a function of magnitude, the probability of fault-to-fault ruptures, and conditional probabilities for foreshock-mainshock triggering. I employ a seismicity simulator...
An introduction to the practical and ethical perspectives on the need to advance and standardize the intracoelomic surgical implantation of electronic tags in fish
R.S. Brown, M.B. Eppard, K.J. Murchie, Jennifer L. Nielsen, S. J. Cooke
2011, Reviews in Fish Biology and Fisheries (21) 1-9
The intracoelomic surgical implantation of electronic tags (including radio and acoustic telemetry transmitters, passive integrated transponders and archival biologgers) is frequently used for conducting studies on fish. Electronic tagging studies provide information on the spatial ecology, behavior and survival of fish in marine and freshwater systems. However, any surgical procedure,...
Geological effects and implications of the 2010 tsunami along the central coast of Chile
R.A. Morton, G. Gelfenbaum, M.L. Buckley, B. M. Richmond
2011, Sedimentary Geology (242) 34-51
Geological effects of the 2010 Chilean tsunami were quantified at five near-field sites along a 200 km segment of coast located between the two zones of predominant fault slip. Field measurements, including topography, flow depths, flow directions, scour depths, and deposit thicknesses, provide insights into the processes and morphological changes associated...
Process-based modeling of tsunami inundation and sediment transport
A. Apotsos, G. Gelfenbaum, B. Jaffe
2011, Journal of Geophysical Research F: Earth Surface (116)
The infrequent and unpredictable nature of tsunamis precludes the use of field experiments to measure the hydrodynamic and sediment transport processes that occur. Instead, these processes are often approximated from laboratory, numerical, and theoretical studies or inferred from observations of the resultant sediment deposits. Here Delft3D, a three-dimensional numerical model,...
Factors driving spatial and temporal variation in production and production/biomass ratio of stream-resident brown trout (Salmo trutta) in Cantabrian streams
J. Lobon-Cervia, G. Gonzalez, P. Budy
2011, Freshwater Biology (56) 2272-2287
1.The objective was to identify the factors driving spatial and temporal variation in annual production (PA) and turnover (production/biomass) ratio (P/BA) of resident brown trout Salmo trutta in tributaries of the Rio Esva (Cantabrian Mountains, Asturias, north-western Spain). We examined annual production (total production of all age-classes over a year)...
Derivation of S and Pb in phanerozoic intrusion-related metal deposits from neoproterozoic sedimentary pyrite, Great Basin, United States
Peter G. Vikre, S.R. Poulson, Alan E. Koenig
2011, Economic Geology (106) 883-912
The thick (≤8 km), regionally extensive section of Neoproterozoic siliciclastic strata (terrigenous detrital succession, TDS) in the central and eastern Great Basin contains sedimentary pyrite characterized by mostly high δ34S values (−11.6 to 40.8‰, >70% exceed 10‰; 51 analyses) derived from reduction of seawater sulfate, and by markedly radiogenic Pb isotopes...
Cosmogenic nuclide and uranium-series dating of old, high shorelines in the western Great Basin, USA
G. Kurth, F. M. Phillips, Marith C. Reheis, J.L. Redwine, James B. Paces
2011, Geological Society of America Bulletin (123) 744-768
Closed-basin pluvial lakes are sensitive recorders of effective moisture, and they provide a terrestrial signal of climate change that can be compared to marine and ice records of glacial-interglacial cycles. Although the most recent deep-lake cycle in the western Great Basin (at ca. 16 ka) has been studied intensively, comparatively...
Columbus crater and other possible groundwater-fed paleolakes of Terra Sirenum, Mars
J.J. Wray, R.E. Milliken, Colin M. Dundas, Gregg A. Swayze, J. C. Andrews-Hanna, A.M. Baldridge, M. Chojnacki, J.L. Bishop, B.L. Ehlmann, S.L. Murchie, Roger N. Clark, F.P. Seelos, L.L. Tornabene, S. W. Squyres
2011, Journal of Geophysical Research E: Planets (116)
Columbus crater in the Terra Sirenum region of the Martian southern highlands contains light‐toned layered deposits with interbedded sulfate and phyllosilicate minerals, a rare occurrence on Mars. Here we investigate in detail the morphology, thermophysical properties, mineralogy, and stratigraphy of these deposits; explore their regional context; and interpret the crater's...
Formation pressure testing at the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: Operational summary, history matching, and interpretations
B. Anderson, S. Hancock, S. Wilson, C. Enger, Timothy S. Collett, R. Boswell, R. Hunter
2011, Marine and Petroleum Geology (28) 478-492
In February 2007, the U.S. Department of Energy, BP Exploration (Alaska), and the U.S. Geological Survey, collected open-hole pressure-response data, as well as gas and water sample collection, in a gas hydrate reservoir (the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well) using Schlumberger's Modular Dynamics Formation Tester (MDT)...