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Page 1799, results 44951 - 44975

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Fire-adaptive trait evolution
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
Until relatively recently the importance of fire and the origin of fire-adaptive traits have received minimal attention from paleoecologists, and appreciation of this importance has varied across the different mediterranean-type climate (MTC) ecosystems. For example, Axelrod (1973) and Raven & Axelrod (1978) wrote extensive treatises on the origins of the...
Permafrost-associated natural gas hydrate occurrences on the Alaska North Slope
Timothy S. Collett, Myung W. Lee, Warren F. Agena, John J. Miller, Kristen A. Lewis, M.V. Zyrianova, R. Boswell, T.L. Inks
2011, Marine and Petroleum Geology (28) 279-294
In the 1960s Russian scientists made what was then a bold assertion that gas hydrates should occur in abundance in nature. Since this early start, the scientific foundation has been built for the realization that gas hydrates are a global phenomenon,...
Late Quaternary environmental change inferred from phytoliths and other soil-related proxies: Case studies from the central and southern Great Plains, USA
C.E. Cordova, W.C. Johnson, R.D. Mandel, M.W. Palmer
2011, Catena (85) 87-108
This study investigates stable carbon isotopes (δ13C), opal phytolith assemblages, burnt phytoliths, microscopic charcoal and Sporormiella spores from modern soils and paleosols in Kansas and Oklahoma. Grass and dicot phytoliths in combination with δ13C are used as proxies for reconstructing the structure of grasslands and woodlands. Burnt grass phytoliths and microscopic charcoal...
Book review: Nonlinear ocean waves and the inverse scattering transform
Eric L. Geist
2011, Pure and Applied Geophysics (168) 1889-1890
Nonlinear Ocean Waves and the Inverse Scattering Transform is a comprehensive examination of ocean waves built upon the theory of nonlinear Fourier analysis. The renowned author, Alfred R. Osborne, is perhaps best known for the discovery of internal solitons in the Andaman Sea during the...
A Digital Hydrologic Network Supporting NAWQA MRB SPARROW Modeling--MRB_E2RF1
J. W. Brakebill, S.E. Terziotti
2011, Report
A digital hydrologic network was developed to support SPAtially Referenced Regression on Watershed attributes (SPARROW) models within selected regions of the United States. These regions correspond with the U.S. Geological Survey's National Water Quality Assessment (NAWQA) Program Major River Basin (MRB) study units 2, 3, 4, 5, and 7 (Preston...
Targeted surveillance for highly pathogenic avian influenza in migratory waterfowl across the conterminous United States: chapter 12
Matthew L. Farnsworth, William L. Kendall, Paul F. Doherty Jr., Ryan S. Miller, Gary C. White, James D. Nichols, Kenneth P. Burnham, Alan B. Franklin
S. Majumdar, F.J. Brenner, J.E. Huffman, R. G. McLean, A.I. Panah, P.J. Pietrobon, S.P. Keeler, S. Shive, editor(s)
2011, Book chapter, Pandemic influenza viruses: Science, surveillance and public health
Introduction of Asian strain H5N1 Highly Pathogenic avian influenca via waterfowl migration is one potential route of entry into the United States. In conjunction with state, tribe, and laboratory partners, the United States Department of Agriculture collected and tested 124,603 wild bird samples in 2006 as part of a national...
Asbestos
Robert Virta
2011, Book chapter, Kirk-Othmer Encyclopedia of Chemical Technology
The term asbestos is a generic designation referring usually to six types of naturally occurring mineral fibers that are or have been commercially exploited. These fibers belong to two mineral groups: serpentines and amphiboles. The serpentine group is represented by a single asbestiform variety-chrysotile. There also are five commercial asbestiform...
Solid sample locations for Fanno Creek, Oregon
Steven Sobieszczyk
2011, Report
Fanno Creek is a tributary to the Tualatin River and flows though parts of the southwest Portland metropolitan area. The stream is heavily influenced by urban runoff and shows characteristic flashy streamflow and poor water quality commonly associated with urban streams. This data set represents the locations where solid samples...
Stream Centerline for Fanno Creek, Oregon
Steven Sobieszczyk
2011, Report
Fanno Creek is a tributary to the Tualatin River and flows though parts of the southwest Portland metropolitan area. The stream is heavily influenced by urban runoff and shows characteristic flashy streamflow and poor water quality commonly associated with urban streams. This data set represents the stream centerline of the...
Water sample locations for Fanno Creek, Oregon
Steven Sobieszczyk
2011, Report
Fanno Creek is a tributary to the Tualatin River and flows though parts of the southwest Portland metropolitan area. The stream is heavily influenced by urban runoff and shows characteristic flashy streamflow and poor water quality commonly associated with urban streams. This data set represents the locations where water-quality samples...
Copper localization, elemental content, and thallus colour in the copper hyperaccumulator lichen Lecanora sierrae from California
O. W. Purvis, J. P. Bennett, J. Spratt
2011, Lichenologist (43) 165-173
An unusual dark blue-green lichen, Lecanora sierrae, was discovered over 30 years ago by Czehura near copper mines in the Lights Creek District, Plumas County, Northern California. Using atomic absorption spectroscopy, Czehura found that dark green lichen samples from Warren Canyon contained 4% Cu in ash and suggested that its...
A Digital Hydrologic Network Supporting NAWQA MRB SPARROW Modeling--MRB_E2RF1WS
J. W. Brakebill, S.E. Terziotti
2011, Report
A digital hydrologic network was developed to support SPAtially Referenced Regression on Watershed attributes (SPARROW) models within selected regions of the United States. These regions correspond with the U.S. Geological Survey's National Water Quality Assessment (NAWQA) Program Major River Basin (MRB) study units 2, 3, 4, 5, and 7 (Preston...
Linking biomarkers to reproductive success of caged fathead minnows in streams with increasing urbanization
J. Crago, Steven R. Corsi, D. Weber, R. Bannerman, R. Klaper
2011, Chemosphere (82) 1669-1674
Reproductive and oxidative stress biomarkers have been recommended as tools to assess the health of aquatic organisms. Though validated in the laboratory, there are few studies that tie a change in gene expression to adverse reproductive or population outcomes in the field. This paper looked at 17 streams with varying...
Use of waveform lidar and hyperspectral sensors to assess selected spatial and structural patterns associated with recent and repeat disturbance and the abundance of sugar maple (Acer saccharum Marsh.) in a temperate mixed hardwood and conifer forest
J.E. Anderson, Mark J. Ducey, A. Fast, M.E. Martin, L. Lepine, M.-L. Smith, T.D. Lee, R.O. Dubayah, M.A. Hofton, P. Hyde, Birgit Peterson, J.B. Blair
2011, Journal of Applied Remote Sensing (5)
Waveform lidar imagery was acquired on September 26, 1999 over the Bartlett Experimental Forest (BEF) in New Hampshire (USA) using NASA's Laser Vegetation Imaging Sensor (LVIS). This flight occurred 20 months after an ice storm damaged millions of hectares of forestland in northeastern North America. Lidar measurements of the amplitude...
Methane oxidation in a crude oil contaminated aquifer: Delineation of aerobic reactions at the plume fringes
R.T. Amos, Barbara A. Bekins, Geoffrey N. Delin, Isabelle M. Cozzarelli, D.W. Blowes, J. D. Kirshtein
2011, Journal of Contaminant Hydrology (125) 13-25
High resolution direct-push profiling over short vertical distances was used to investigate CH4 attenuation in a petroleum contaminated aquifer near Bemidji, Minnesota. The contaminant plume was delineated using dissolved gases, redox sensitive components, major ions, carbon isotope ratios in CH4 and CO2, and the presence of methanotrophic bacteria. Sharp redox gradients were observed near the...
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...
Quantification of a greenhouse hydrologic cycle from equatorial to polar latitudes: The mid-Cretaceous water bearer revisited
M.B. Suarez, Luis A. Gonzalez, Greg A. Ludvigson
2011, Palaeogeography, Palaeoclimatology, Palaeoecology (307) 301-312
This study aims to investigate the global hydrologic cycle during the mid-Cretaceous greenhouse by utilizing the oxygen isotopic composition of pedogenic carbonates (calcite and siderite) as proxies for the oxygen isotopic composition of precipitation. The data set builds on the Aptian–Albian sphaerosiderite δ18O data set presented by Ufnar et...
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)...
Bounding species distribution models
Thomas J. Stohlgren, Catherine S. Jarnevich, Wayne E. Esaias, Jeffery T. Morisette
2011, Current Zoology (57) 642-647
Species distribution models are increasing in popularity for mapping suitable habitat for species of management concern. Many investigators now recognize that extrapolations of these models with geographic information systems (GIS) might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best...
Causes of systematic over- or underestimation of low streamflows by use of index-streamgage approaches in the United States
K. Eng, J.E. Kiang, Y.-Y. Chen, D.M. Carlisle, G.E. Granato
2011, Hydrological Processes (25) 2211-2220
Low-flow characteristics can be estimated by multiple linear regressions or the index-streamgage approach. The latter transfers streamflow information from a hydrologically similar, continuously gaged basin ('index streamgage') to one with a very limited streamflow record, but often results in biased estimates. The application of the index-streamgage approach can be generalized...
Formulation of a correlated variables methodology for assessment of continuous gas resources with an application to the Woodford play, Arkoma Basin, eastern Oklahoma
Ricardo A. Olea, D.W. Houseknecht, C.P. Garrity, T. A. Cook
2011, Boletin Geologico y Minero (122) 483-496
Shale gas is a form of continuous unconventional hydrocarbon accumulation whose resource estimation is unfeasible through the inference of pore volume. Under these circumstances, the usual approach is to base the assessment on well productivity through estimated ultimate recovery (EUR). Unconventional resource assessments that consider uncertainty are typically done by...
Didymosphenia geminata: Algal blooms in oligotrophic streams and rivers
P.V. Sundareshwar, S. Upadhayay, M. Abessa, S. Honomichl, B. Berdanier, S. A. Spaulding, C. Sandvik, A. Trennepohl
2011, Geophysical Research Letters (38)
In recent decades, the diatom Didymosphenia geminata has emerged as nuisance species in river systems around the world. This periphytic alga forms large "blooms" in temperate streams, presenting a counterintuitive result: the blooms occur primarily in oligotrophic streams and rivers, where phosphorus (P) availability typically limits primary production. The goal...
Tiny intraplate earthquakes triggered by nearby episodic tremor and slip in Cascadia
J.E. Vidale, A.J. Hotovec, A. Ghosh, K. C. Creager, J. Gomberg
2011, Geochemistry, Geophysics, Geosystems (12)
Episodic tremor and slip (ETS) has been observed in many subduction zones, but its mechanical underpinnings as well as its potential for triggering damaging earthquakes have proven difficult to assess. Here we use a seismic array in Cascadia of unprecedented density to monitor seismicity around a moderate 16 day ETS...
Geology and petroleum potential of the north and east margins of the Siberian Craton, north of the Arctic Circle
T. R. Klett, C. J. Wandrey, Janet K. Pitman
2011, Geological Society Memoir 413-431
The Siberian Craton consists of crystalline rocks and superimposed Precambrian sedimentary rocks deposited in rift basins. Palaeozoic rocks, mainly carbonates, were deposited along the margins of the craton to form an outwardly younger concentric pattern that underlies an outward-thickening Mesozoic sedimentary section. The north and east margins of the Siberian...
Long-term biases in geomagnetic K and aa indices
Jeffrey J. Love
2011, Annales Geophysicae (29) 1365-1375
Analysis is made of the geomagnetic-activity aa index and its source K-index data from groups of ground-based observatories in Britain, and Australia, 1868.0–2009.0, solar cycles 11–23. The K data show persistent biases, especially for high (low) K-activity levels at British (Australian) observatories. From examination of multiple subsets of the K data we infer that the biases are not...