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Page 1477, results 36901 - 36925

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Not all publications have extents, not all extents are completely accurate
Step-changes in the physical, chemical and biological characteristics of the Gulf of Maine, as documented by the GNATS time series
William M. Balch, D.T. Drapeau, B.C. Bowler, Thomas G. Huntington
2012, Marine Ecology Progress Series (450) 11-35
We identify step-changes in the physical, chemical and biological characteristics of the Gulf of Maine (GoM) using the Gulf of Maine North Atlantic Time Series (GNATS), a series of oceanographic measurements obtained between September 1998 and December 2010 along a transect in the GoM running from Portland, ME, to Yarmouth,...
Integrated characterization of the geologic framework of a contaminated site in West Trenton, New Jersey
Karl J. Ellefsen, William C. Burton, Pierre J. Lacombe
2012, Journal of Applied Geophysics (79) 71-81
Fractured sedimentary bedrock and groundwater at the former Naval Air Warfare Center in West Trenton, New Jersey (United States of America) are contaminated with chlorinated solvents. Predicting contaminant migration or removing the contaminants requires an understanding of the geology. Consequently, the geologic framework near the site was characterized with four...
A state-based national network for effective wildlife conservation
Vicky J. Meretsky, Lynn A. Maguire, Frank W. Davis, David M. Stoms, J. Michael Scott, Dennis Figg, Dale D. Goble, Brad Griffith, Scott E. Henke, Jacqueline Vaughn, Steven L. Yaffee
2012, BioScience (62) 970-976
State wildlife conservation programs provide a strong foundation for biodiversity conservation in the United States, building on state wildlife action plans. However, states may miss the species that are at the most risk at rangewide scales, and threats such as novel diseases and climate change increasingly act at regional and...
Mycoplasma testudineum in free-ranging desert tortoises, Gopherus agassizii
Elliott R. Jacobson, Kristin H. Berry
2012, Journal of Wildlife Diseases (48) 1063-1068
We performed clinico-pathological evaluations of 11 wild Agassiz's desert tortoises (Gopherus agassizii) from a translocation project in the central Mojave Desert, California, USA. Group 1 consisted of nine tortoises that were selected primarily due to serologic status, indicating exposure to Mycoplasma testudineum (seven) or both M. agassizii and M. testudineum...
Ancient impact and aqueous processes at Endeavour Crater, Mars
S. W. Squyres, R. E. Arvidson, J.F. Bell III, F.J. Calef III, B.C. Clark, B. A. Cohen, L.A. Crumpler, P. A. de Souza Jr., W. H. Farrand, Ralf Gellert, J. Grant, Kenneth E. Herkenhoff, J.A. Hurowitz, J. R. Johnson, B.L. Jolliff, A.H. Knoll, R. Li, S. M. McLennan, D. W. Ming, D. W. Mittlefehldt, T. J. Parker, G. Paulsen, M.S. Rice, S. W. Ruff, C. Schroder, A. S. Yen, K. Zacny
2012, Science (336) 570-576
The rover Opportunity has investigated the rim of Endeavour Crater, a large ancient impact crater on Mars. Basaltic breccias produced by the impact form the rim deposits, with stratigraphy similar to that observed at similar-sized craters on Earth. Highly localized zinc enrichments in some breccia materials suggest hydrothermal alteration of...
Analysis of rainfall-induced slope instability using a field of local factor of safety
Ning Lu, Başak Şener-Kaya, Alexandra Wayllace, Jonathan W. Godt
2012, Water Resources Research (48)
Slope-stability analyses are mostly conducted by identifying or assuming a potential failure surface and assessing the factor of safety (FS) of that surface. This approach of assigning a single FS to a potentially unstable slope provides little insight on where the failure initiates or the ultimate geometry and location of...
A remote-sensing, GIS-based approach to identify, characterize, and model spawning habitat for fall-run chum salmon in a sub-arctic, glacially fed river
Lisa Wirth, Amanda Rosenberger, Anupma Prakash, Rudiger Gens, F. Joseph Margraf, Toshihide Hamazaki
2012, Transactions of the American Fisheries Society (141) 1349-1363
At northern limits of a species’ distribution, fish habitat requirements are often linked to thermal preferences, and the presence of overwintering habitat. However, logistical challenges and hydrologic processes typical of glacial systems could compromize the identification of these habitats, particularly in large river environments. Our goal was to identify and...
Phosphorite-hosted zinc and lead mineralization in the Sekarna deposit (Central Tunisia)
Hechmi Garnit, Salah Bouhel, Donatella Barca, Craig A. Johnson, Chaker Chtara
2012, Mineralium Deposita (47) 545-562
The Sekarna Zn–Pb deposit is located in Central Tunisia at the northeastern edge of the Cenozoic Rohia graben. Mineralization comprises two major ore types: (1) disseminated Zn–Pb sulfides that occur as lenses in sedimentary phosphorite layers and (2) cavity-filling zinc oxides (calamine-type ores) that crosscut Late Cretaceous and Early Eocene...
Predator evasion by white-tailed deer fawns
Troy W. Grovenburg, Kevin L. Monteith, Robert W. Klaver, Jonathan A. Jenks
2012, Animal Behaviour (84) 59-65
Despite their importance for understanding predator–prey interactions, factors that affect predator evasion behaviours of offspring of large ungulates are poorly understood. Our objective was to characterize the influence of selection and availability of escape cover and maternal presence on predator evasion by white-tailed deer, Odocoileus virginianus, fawns in the northern...
Gravity fluctuations induced by magma convection at Kilauea Volcano, Hawai'i
Daniele Carbone, Michael P. Poland
2012, Geology (40) 803-806
Convection in magma chambers is thought to play a key role in the activity of persistently active volcanoes, but has only been inferred indirectly from geochemical observations or simulated numerically. Continuous microgravity measurements, which track changes in subsurface mass distribution over time, provide a potential method for characterizing convection in...
The IUGS/IAGC Task Group on Global Geochemical Baselines
David B. Smith, Xueqiu Wang, Shaun Reeder, Alecos Demetriades
2012, Earth Science Frontiers (19) 1-6
The Task Group on Global Geochemical Baselines, operating under the auspices of both the International Union of Geological Sciences (IUGS) and the International Association of Geochemistry (IAGC), has the long-term goal of establishing a global geochemical database to document the concentration and distribution of chemical elements in the Earth’s surface...
On the use of wave parameterizations and a storm impact scaling model in National Weather Service Coastal Flood and decision support operations
Anthony Mignone, H. Stockdon, M. Willis, J.W. Cannon, R. Thompson
2012, Conference Paper, 92nd American Meteorological Society Annual Meeting, January 22-26, 2012
National Weather Service (NWS) Weather Forecast Offices (WFO) are responsible for issuing coastal flood watches, warnings, advisories, and local statements to alert decision makers and the general public when rising water levels may lead to coastal impacts such as inundation, erosion, and wave battery. Both extratropical and tropical cyclones can...
Stable isotopes identify dietary changes associated with beak deformities in Black-Capped Chickadees (Poecile atricapillus)
Caroline R. Van Hemert, Colleen M. Handel, Diane M. O’Brien
2012, The Auk (129) 460-466
A large number of beak deformities of unknown etiology have recently been reported in Black-capped Chickadees (Poecile atricapillus) and other resident avian species in Alaska. We investigated the potential association between diet and beak deformities. We analyzed carbon (δ13C) and nitrogen (δ15N) isotopes in whole blood of Black-capped Chickadees captured...
Primary mapping and stratigraphic data and field methods for the Snowmastodon Project
Carol Lucking, Kirk R. Johnson, Jeffery S. Pigati, Ian Miller
2012, Technical Report 2012-04
During the Snowmastodon Project, many different people collected data for a wide array of purposes under a variety of conditions. Early in the process and in an attempt to provide project-wide consistency, Kirk Johnson appointed Carol Lucking as the project’s data manager both in the field and the lab. She...
Data-driven modeling of surface temperature anomaly and solar activity trends
Michael J. Friedel
2012, Environmental Modelling and Software (37) 217-232
A novel two-step modeling scheme is used to reconstruct and analyze surface temperature and solar activity data at global, hemispheric, and regional scales. First, the self-organizing map (SOM) technique is used to extend annual modern climate data from the century to millennial scale. The SOM component planes are used to...
Methods for simulating solute breakthrough curves in pumping groundwater wells
J. Jeffrey Starn, Amvrossios C. Bagtzoglou, Gary A. Robbins
2012, Computers & Geosciences (48) 244-255
In modeling there is always a trade-off between execution time and accuracy. For gradient-based parameter estimation methods, where a simulation model is run repeatedly to populate a Jacobian (sensitivity) matrix, there exists a need for rapid simulation methods of known accuracy that can decrease execution time, and thus make the...
A historical estimate of apparent survival of American oystercatcher (Haematopus palliatus) in Virginia
Erica Nol, Sean P. Murphy, Michael D. Cadman
2012, Waterbirds (35) 631-635
Using mark-recapture models, apparent survival was estimated from older banding and re-sighting data (1978–1983) of American Oystercatchers (Haematopus palliatus) nesting on beaches and in salt marshes of coastal Virginia, USA. Oystercatchers nesting in salt marshes exhibited higher apparent survival (0.94 ±0.03) than birds nesting on beaches (0.81 ±0.06), a difference...
The effects of feral cats on insular wildlife: the Club-Med syndrome
Steve C. Hess, Raymond M. Danner
R. M. Timm, editor(s)
2012, Conference Paper, Proceedings of the Vertebrate Pest Conference
Domestic cats have been introduced to many of the world‘s islands where they have been particularly devastating to insular wildlife which, in most cases, evolved in the absence of terrestrial predatory mammals and feline diseases. We review the effects of predation, feline diseases, and the life history characteristics of feral...
Geology and sequence stratigraphy of undiscovered oil and gas resources in conventional and continuous petroleum systems in the Upper Cretaceous Eagle Ford Group and related strata, U.S. Gulf Coast Region
Russell F. Dubiel, Ofori N. Pearson, Janet K. Pitman, Krystal M. Pearson, Scott A. Kinney
2012, Gulf Coast Association of Geological Societies Transactions (62) 57-72
The U.S. Geological Survey (USGS) recently assessed the technically recoverable undiscovered oil and gas onshore and in State waters of the Gulf Coast region of the United States. The USGS defined three assessment units (AUs) with potential undiscovered conventional and continuous oil and gas resources in Upper Cretaceous (Cenomanian to...
Late Quaternary sedimentological and climate changes at Lake Bosumtwi Ghana: new constraints from laminae analysis and radiocarbon age modeling
Timothy M. Shanahan, J. Warren Beck, Jonathan T. Overpeck, Nicholas P. McKay, Jeffrey S. Pigati, John A. Peck, Christopher A. Scholz, Clifford W. Heil Jr., John W. King
2012, Palaeogeography, Palaeoclimatology, Palaeoecology (361-362) 49-60
The Lake Bosumtwi sediment record represents one of the longest and highest-resolution terrestrial records of paleoclimate change available from sub-Saharan Africa. Here we report a new sediment age model framework for the last ~ 45 cal kyr of sedimentation using a combination of high-resolution radiocarbon dating, Bayesian age-depth modeling and...
Holocene dune formation at Ash Meadows National Wildlife Area, Nevada, USA
Nicholas Lancaster, Shannon Mahan
2012, Quaternary Research (78) 266-274
Small isolated dune fields in the northern Mojave Desert are important centers of biodiversity and archaeological occupation sites. Currently dunes at Ash Meadows, Nevada, are stabilized by vegetation and are experiencing erosion of their upwind margins, indicating a negative sediment budget. New OSL ages from dunes at Ash Meadows indicate...
Emerging contaminants at a closed and an operating landfill in Oklahoma
William J. Andrews, Jason R. Masoner, Isabelle M. Cozzarelli
2012, Groundwater Monitoring & Remediation (32) 120-130
Landfills are the final depositories for a wide range of solid waste from both residential and commercial sources, and therefore have the potential to produce leachate containing many organic compounds found in consumer products such as pharmaceuticals, plasticizers, disinfectants, cleaning agents, fire retardants, flavorings, and preservatives, known as emerging contaminants...
Modeling responses of large-river fish populations to global climate change through downscaling and incorporation of predictive uncertainty
Mark L. Wildhaber, Christopher K. Wikle, Christopher J. Anderson, Kristie J. Franz, Edward H. Moran, Rima Dey
Helmut Mader, Julia Kraml, editor(s)
2012, Conference Paper, 9th International Symposium on Ecohydraulics 2012 Proceedings
Climate change operates over a broad range of spatial and temporal scales. Understanding its effects on ecosystems requires multi-scale models. For understanding effects on fish populations of riverine ecosystems, climate predicted by coarse-resolution Global Climate Models must be downscaled to Regional Climate Models to watersheds to river hydrology...