Well log characterization of natural gas-hydrates
Timothy S. Collett, Myung W. Lee
2012, Book
In the last 25 years there have been significant advancements in the use of well-logging tools to acquire detailed information on the occurrence of gas hydrates in nature: whereas wireline electrical resistivity and acoustic logs were formerly used to identify gas-hydrate occurrences in wells drilled in Arctic permafrost environments, more...
Magnitude Estimates of M7.3-7.8 for the 1811-1812 New Madrid and M7.0 for the 1886 Charleston Earthquakes from a Monte Carlo Analysis of Mean MMIs
Chris H. Cramer, Oliver S. Boyd
2012, Book, Eastern Section-SSA 2012 Meeting Report
No abstract available...
A fine-scale assessment of using barriers to conserve native stream salmonids: a case study in Akokala Creek, Glacier National Park, USA
Clint C. Muhlfeld, Vincent S. D'Angelo, S.T. Kalinowski, Erin L. Landguth, C.C. Downs, J. Tohtz, Jeffrey L. Kershner
2012, Open Fish Science Journal (5) 9-20
Biologists are often faced with the difficult decision in managing native salmonids of where and when to install barriers as a conservation action to prevent upstream invasion of nonnative fishes. However, fine-scale approaches to assess long-term persistence of populations within streams and watersheds chosen for isolation management are often lacking....
Shrews, rats, and a polecat in "the pardoner’s tale"
Sandy Feinstein, Neal Woodman
Carolynn Van Dyke, editor(s)
2012, Book chapter, Rethinking Chaucerian beasts
While historically existing animals and literary animal characters inform allegorical and metaphorical characterization in The Canterbury Tales, figurative usage does not erase recognition of the material animal. "The Pardoner's Tale," for one, challenges the terms of conventional animal metaphors by refocusing attention on common animals as common animals and common...
USGS National Wildlife Health Center mortality report
Barbara L. Bodenstein
2012, Wildlife Disease Association Newsletter 10-11
No abstract available....
Geostatistical population-mixture approach to unconventional-resource assessment with an application to the Woodford Gas Shale, Arkoma Basin, eastern Oklahoma
Ricardo A. Olea, Ronald Charpentier, Troy A. Cook, David W. Houseknecht, Christopher P. Garrity
David W. Houseknecht, Ronald R. Charpentier, editor(s)
2012, SPE Reservoir Evaluation & Engineering (15) 554-562
Evaluation of resources such as tight sands and gas shales requires the formulation of assessment models that are different from those used for the inference of conventional resources. Formulations in present use are based in classical statistics that ignore the partly organized and partly random geographical variation of attributes related...
Effect of organic-matter type and thermal maturity on methane adsorption in shale-gas systems
Tongwei Zhang, Geoffrey S. Ellis, Stephen C. Ruppel, Kitty Milliken, Rongsheng Yang
2012, Organic Geochemistry (47) 120-131
A series of methane (CH4) adsorption experiments on bulk organic rich shales and their isolated kerogens were conducted at 35 °C, 50 °C and 65 °C and CH4 pressure of up to 15 MPa under dry conditions. Samples from the Eocene Green River Formation, Devonian–Mississippian Woodford Shale and Upper Cretaceous...
A circumpolar monitoring framework for polar bears
Dag Vongraven, Jon Aars, Steven C. Amstrup, Stephen N. Atkinson, Stanislav Belikov, Erik W. Born, T.D. DeBruyn, Andrew E. Derocher, George M. Durner, Michael J. Gill, Nicholas J. Lunn, Martyn E. Obbard, Jack Omelak, Nikita Ovsyanikov, Elizabeth L. Peacock, E.E. Richardson, Vicki Sahanatien, Ian Stirling, Øystein Wiig
2012, Ursus (23) 1-66
Polar bears (Ursus maritimus) occupy remote regions that are characterized by harsh weather and limited access. Polar bear populations can only persist where temporal and spatial availability of sea ice provides adequate access to their marine mammal prey. Observed declines in sea ice availability will continue as long as greenhouse...
Spatiotemporal analysis of black spruce forest soils and implications for the fate of C
Jennifer W. Harden, Kristen L. Manies, Jonathan O'Donnell, Kristofer Johnson, Steve Frolking, Zhaosheng Fan
2012, Journal of Geophysical Research (117)
Post-fire storage of carbon (C) in organic-soil horizons was measured in one Canadian and three Alaskan chronosequences in black spruce forests, together spanning stand ages of nearly 200 yrs. We used a simple mass balance model to derive estimates of inputs, losses, and accumulation rates of C on timescales of...
The Spar Lake strata-Bound Cu-Ag deposit formed across a mixing zone between trapped natural gas and metals-bearing brine
Timothy S. Hayes, Gary P. Landis, Joseph F. Whelan, Robert O. Rye, Richard J. Moscati
2012, Economic Geology (107) 1223-1249
Ore formation at the Spar Lake red bed-associated strata-bound Cu deposit took place across a mixing and reaction zone between a hot oxidized metals-transporting brine and a reservoir of “sour” (H2S-bearing) natural gas trapped in the host sandstones. Fluid inclusion volatile analyses have very high CH4 concentrations (≥1 mol %...
The effects of permafrost thaw on soil hydrologic, thermal, and carbon dynamics in an Alaskan peatland
Jonathan A. O’Donnell, M. Torre Jorgenson, Jennifer W. Harden, A. David McGuire, Mikhail Z. Kanevskiy, Kimberly P. Wickland
2012, Ecosystems (15) 213-229
Recent warming at high-latitudes has accelerated permafrost thaw in northern peatlands, and thaw can have profound effects on local hydrology and ecosystem carbon balance. To assess the impact of permafrost thaw on soil organic carbon (OC) dynamics, we measured soil hydrologic and thermal dynamics and soil OC stocks across a...
Selecting sagebrush seed sources for restoration in a variable climate: ecophysiological variation among genotypes
Matthew J. Germino
2012, Report, Great Basin Native Plant Selection and Increase Project 2011 Progress Report
Big sagebrush (Artemisia tridentata) communities dominate a large fraction of the United States and provide critical habitat for a number of wildlife species of concern. Loss of big sagebrush due to fire followed by poor restoration success continues to reduce ecological potential of this ecosystem type, particularly in the Great...
On modeling weak sinks in MODPATH
Daniel B. Abrams, Henk Haitjema, Leon J. Kauffman
2012, Ground Water (51) 597-602
Regional groundwater flow systems often contain both strong sinks and weak sinks. A strong sink extracts water from the entire aquifer depth, while a weak sink lets some water pass underneath or over the actual sink. The numerical groundwater flow model MODFLOW may allow a sink cell to act as...
Bacterial and enchytraeid abundance accelerate soil carbon turnover along a lowland vegetation gradient in interior Alaska
M. P. Waldrop, Jennifer W. Harden, M.R. Turetsky, D.G. Petersen, A. D. McGuire, M.J.I. Briones, Amber C. Churchill, D.H. Doctor, L.E. Pruett
2012, Soil Biology and Biochemistry (50) 188-198
Boreal wetlands are characterized by a mosaic of plant communities, including forests, shrublands, grasslands, and fens, which are structured largely by changes in topography and water table position. The soil associated with these plant communities contain quantitatively and qualitatively different forms of soil organic matter (SOM) and nutrient availability that...
Root zone water quality model (RZWQM2): Model use, calibration and validation
Liwang Ma, Lajpat Ahuja, B. T. Nolan, Robert Malone, Thomas Trout, Z. Qi
2012, Transactions of the ASABE (55) 1425-1446
The Root Zone Water Quality Model (RZWQM2) has been used widely for simulating agricultural management effects on crop production and soil and water quality. Although it is a one-dimensional model, it has many desirable features for the modeling community. This article outlines the principles of calibrating the model component by...
Predation rates, timing, and predator composition for Scoters (Melanitta spp.) in marine habitats
Eric J. Anderson, Daniel Esler, Boyd W. Sean, Joseph Evenson, David R. Nysewander, David H. Ward, Rian D. Dickson, Brian D. Uher-Koch, C.S. Vanstratt, Jerry W. Hupp
2012, Canadian Journal of Zoology (90) 42-50
Studies of declining populations of sea ducks have focused mainly on bottom-up processes with little emphasis on the role of predation. We identified 11 potential predators of White-winged Scoters (Melanitta fusca (L., 1758)) and Surf Scoters (Melanitta perspicillata (L., 1758)) in North American marine habitats. However, of 596 Scoters marked...
California spotted owls
Suzanne C. Roberts, M. North
2012, General Technical Report PSW-GTR-237-5
California spotted owls (Strix occidentalis occidentalis) are habitat specialists that are strongly associated with late-successional forests. For nesting and roosting, they require large trees and snags embedded in a stand with a complex forest structure (Blakesley et al. 2005, Gutiérrez et al. 1992, Verner et al. 1992b). In mixed-conifer forests...
Soil-occupancy effects of invasive and native grassland plant species on composition and diversity of mycorrhizal associations
Nicholas R. Jordan, Laura Aldrich-Wolfe, Sheri C. Huerd, Diane L. Larson, Gary Muehlbauer
2012, Invasive Plant Science and Management (5) 494-505
Diversified grasslands that contain native plant species can produce biofuels, support sustainable grazing systems, and produce other ecosystem services. However, ecosystem service production can be disrupted by invasion of exotic perennial plants, and these plants can have soil-microbial “legacies” that may interfere with establishment and maintenance of diversified grasslands even...
Range overlap and individual movements during breeding season influence genetic relationships of caribou herds in south-central Alaska
Gretchen H. Roffler, Layne G. Adams, Sandra L. Talbot, George K. Sage, Bruce W. Dale
2012, Canadian Journal of Zoology (93) 1318-1330
North American caribou (Rangifer tarandus) herds commonly exhibit little nuclear genetic differentiation among adjacent herds, although available evidence supports strong demographic separation, even for herds with seasonal range overlap. During 1997–2003, we studied the Mentasta and Nelchina caribou herds in south-central Alaska using radiotelemetry to determine individual movements and range...
Diversity of nitrogen isotopes and protein status in caribou: implications for monitoring northern ungulates
David D. Gustine, Perry S. Barboza, James P. Lawler, Layne G. Adams, Kathy L. Parker, Steve M. Arthur, Brad S. Shults
2012, Journal of Mammalogy (93) 778-790
Nutritional condition is an important determinant of productivity and survival in caribou (Rangifer tarandus). We used samples of excreta (n = 1,150) to estimate diet composition from microhistology and 2 isotopic proxies of protein status for 2 ecotypes of caribou in 4 herds in late winter (2006–2008). Isotopes of nitrogen...
The science, information, and engineering needed to manage water availability and quality in 2050
Robert M. Hirsch
2012, Book chapter, Toward a sustainable water future: Visions for 2050
This chapter explores four water resources issues: 1) hydrologic variability, hazards, water supply and ecosystem preservation; 2) urban landscape design; 3) non-point source water quality, and 4) climate change, resiliency, and nonstationarity. It also considers what science, technology, and engineering practice may be needed in the coming decades to...
Explosive eruptions triggered by rockfalls at Kīlauea volcano, Hawaii
Tim R. Orr, Weston A. Thelen, Matthew R. Patrick, Donald A. Swanson, David C. Wilson
2012, Geology (41) 207-210
Ongoing eruptive activity at Kīlauea volcano’s (Hawai‘i) summit has been controlled in part by the evolution of its vent from a 35-m-diameter opening into a collapse crater 150 m across. Geologic observations, in particular from a network of webcams, have provided an unprecedented look at collapse crater development, lava lake...
Near-surface, marine seismic-reflection data defines potential hydrogeologic confinement bypass in a tertiary carbonate aquifer, southeastern Florida
Kevin J. Cunningham, Cameron Walker, Richard L. Westcott
2012, SEG Technical Program Expanded Abstracts (2012) 1-6
Approximately 210 km of near-surface, high-frequency, marine seismic-reflection data were acquired on the southeastern part of the Florida Platform between 2007 and 2011. Many high-resolution, seismic-reflection profiles, interpretable to a depth of about 730 m, were collected on the shallow-marine shelf of southeastern Florida in water as shallow as 1...
Small population size of Pribilof Rock Sandpipers confirmed through distance-sampling surveys in Alaska
Daniel R. Ruthrauff, T. Lee Tibbitts, Robert E. Gill Jr., Maksim N. Dementyev, Colleen M. Handel
2012, Condor (114) 544-551
The Rock Sandpiper (Calidris ptilocnemis) is endemic to the Bering Sea region and unique among shorebirds in the North Pacific for wintering at high latitudes. The nominate subspecies, the Pribilof Rock Sandpiper (C. p. ptilocnemis), breeds on four isolated islands in the Bering Sea and appears to spend the winter...
Heavy tails and earthquake probabilities
William L. Ellsworth
2012, Seismological Research Letters (83) 483-485
The 21st century has already seen its share of devastating earthquakes, some of which have been labeled as “unexpected,” at least in the eyes of some seismologists and more than a few journalists. A list of seismological surprises could include the 2004 Sumatra-Andaman Islands; 2008 Wenchuan, China; 2009 Haiti; 2011...