A first look at the petroleum geology of the Lomonosov Ridge microcontinent, Arctic Ocean
Thomas E. Moore, Arthur Grantz, Janet K. Pitman, Philip J. Brown
2011, Geological Society Memoir (35) 751-769
The Lomonosov microcontinent is an elongated continental fragment that transects the Arctic Ocean between North America and Siberia via the North Pole. Although it lies beneath polar pack ice, the geological framework of the microcontinent is inferred from sparse seismic reflection data, a few cores, potential field data and the...
Fish entrainment rates through towboat propellers in the Upper Mississippi and Illinois rivers
Killgore K. Jack, Leandro E. Miranda, C.E. Murphy, D.M. Wolff, J.J. Hoover, T.M. Keevin, S.T. Maynord, M.A. Cornish
2011, Transactions of the American Fisheries Society (140) 570-581
A specially designed net was used to study fish entrainment and injury through towboat propellers in 13 pools of the Upper Mississippi and Illinois rivers. The net was attached to the stern of a 48.8‐m‐long towboat with twin propellers (in Kort propulsion nozzles), and sampling typically took place while the...
When a habitat freezes solid: Microorganisms over-winter within the ice column of a coastal Antarctic lake
C.M. Foreman, M. Dieser, M. Greenwood, R.M. Cory, J. Laybourn-Parry, John T. Lisle, C. Jaros, P.L. Miller, Y.-P. Chin, Diane M. McKnight
2011, FEMS Microbiology Ecology (76) 401-412
A major impediment to understanding the biology of microorganisms inhabiting Antarctic environments is the logistical constraint of conducting field work primarily during the summer season. However, organisms that persist throughout the year encounter severe environmental changes between seasons. In an attempt to bridge this gap, we collected ice core samples...
Aeolian nutrient fluxes following wildfire in sagebrush steppe: Implications for soil carbon storage
N.J. Hasselquist, M.J. Germino, Joel B. Sankey, L.J. Ingram, N.F. Glenn
2011, Biogeosciences Discussions (8) 8323-8349
. Pulses of aeolian transport following fire can profoundly affect the biogeochemical cycling of nutrients in semi-arid and arid ecosystems. Our objective was to determine horizontal nutrient fluxes occurring in the saltation zone during an episodic pulse of aeolian transport that occurred following a wildfire in a semi-arid sagebrush steppe...
What is the role of fresh groundwater and recirculated seawater in conveying nutrients to the coastal ocean?
Yishai Weinstein, Yoseph Yechieli, Yehuda Shalem, William C. Burnett, Peter W. Swarzenski, Barak Herut
2011, Environmental Science and Technology (45) 5195-5200
Submarine groundwater discharge (SGD) is a major process operating at the land-sea interface. Quantifying the SGD nutrient loads and the marine/terrestrial controls of this transport is of high importance, especially in oligotrophic seas such as the eastern Mediterranean. The fluxes of nutrients in groundwater discharging from the seafloor at Dor...
Simulating adsorption of U(VI) under transient groundwater flow and hydrochemistry: Physical versus chemical nonequilibrium model
J. Greskowiak, M.B. Hay, H. Prommer, C. Liu, V.E.A. Post, R. Ma, J.A. Davis, C. Zheng, J.M. Zachara
2011, Water Resources Research (47)
Coupled intragrain diffusional mass transfer and nonlinear surface complexation processes play an important role in the transport behavior of U(VI) in contaminated aquifers. Two alternative model approaches for simulating these coupled processes were analyzed and compared: (1) the physical nonequilibrium approach that explicitly accounts for aqueous speciation and instantaneous surface...
Spatiotemporal earthquake clusters along the North Anatolian fault zone offshore Istanbul
Fatih Bulut, William L. Ellsworth, Marco Bohnhoff, Mustafa Aktar, Georg Dresen
2011, Bulletin of the Seismological Society of America (101) 1759-1768
We investigate earthquakes with similar waveforms in order to characterize spatiotemporal microseismicity clusters within the North Anatolian fault zone (NAFZ) in northwest Turkey along the transition between the 1999 İzmit rupture zone and the Marmara Sea seismic gap. Earthquakes within distinct activity clusters are relocated with cross-correlation derived relative travel...
The high life: Transport of microbes in the atmosphere
D.J. Smith, Dale W. Griffin, D.A. Jaffe
2011, Eos, Transactions, American Geophysical Union (92) 249-250
Microbes (bacteria, fungi, algae, and viruses) are the most successful types of life on Earth because of their ability to adapt to new environments, reproduce quickly, and disperse globally. Dispersal occurs through a number of vectors, such as migrating animals or the hydrological cycle, but transport by wind may be...
Sea ice loss enhances wave action at the Arctic coast
I. Overeem, R. Scott Anderson, C.W. Wobus, Gary D. Clow, Frank E. Urban, N. Matell
2011, Geophysical Research Letters (38)
Erosion rates of permafrost coasts along the Beaufort Sea accelerated over the past 50 years synchronously with Arctic‐wide declines in sea ice extent, suggesting a causal relationship between the two. A fetch‐limited wave model driven by sea ice position and local wind data from northern Alaska indicates that the exposure...
Effects of black bear relocation on elk calf recruitment at Great Smoky Mountains National Park
J. Yarkovich, J. D. Clark, J.L. Murrow
2011, Journal of Wildlife Management (75) 1145-1154
Previous research from 2001 to 2006 on an experimentally released elk (Cervus elaphus) population at Great Smoky Mountains National Park (GSMNP or Park) indicated that calf recruitment (i.e., calves reaching 1 yr of age per adult female elk) was low (0.306, total SE = 0.090) resulting in low or negative population growth...
The use (and misuse) of sediment traps in coral reef environments: Theory, observations, and suggested protocols
C. D. Storlazzi, M.E. Field, Michael H. Bothner
2011, Coral Reefs (30) 23-38
Sediment traps are commonly used as standard tools for monitoring “sedimentation” in coral reef environments. In much of the literature where sediment traps were used to measure the effects of “sedimentation” on corals, it is clear from deployment descriptions and interpretations of the resulting data that information derived from sediment...
Transitions of interaction outcomes in a uni-directional consumer-resource system
Y. Wang, Donald L. DeAngelis
2011, Journal of Theoretical Biology (280) 43-49
A uni-directional consumer–resource system of two species is analyzed. Our aim is to understand the mechanisms that determine how the interaction outcomes depend on the context of the interaction; that is, on the model parameters. The dynamic behavior of the model is described and, in particular, it is demonstrated that no periodic...
Patterns of coral disease across the Hawaiian Archipelago: Relating disease to environment
G.S. Aeby, G.J. Williams, E.C. Franklin, J. Kenyon, E.F. Cox, S. Coles, Thierry M. Work
2011, PLoS ONE (6)
In Hawaii, coral reefs occur across a gradient of biological (host abundance), climatic (sea surface temperature anomalies) and anthropogenic conditions from the human-impacted reefs of the main Hawaiian Islands (MHI) to the pristine reefs of the northwestern Hawaiian Islands (NWHI). Coral disease surveys were conducted at 142 sites from across...
The effect of travel loss on evolutionarily stable distributions of populations in space
Donald L. DeAngelis, G.S.K. Wolkowicz, Y. Lou, Y. Jiang, M. Novak, R. Svanback, M.S. Araujo, Y.S. Jo, E.A. Cleary
2011, American Naturalist (178) 15-29
A key assumption of the ideal free distribution (IFD) is that there are no costs in moving between habitat patches. However, because many populations exhibit more or less continuous population movement between patches and traveling cost is a frequent factor, it is important to determine the effects of costs on...
Three-dimensional model of an ultramafic feeder system to the Nikolai Greenstone mafic large igneous province, central Alaska Range
Jonathan M.G. Glen, Jeanine M. Schmidt, G. G. Connard
2011, Geochemistry, Geophysics, Geosystems (12)
The Amphitheater Mountains and southern central Alaska Range expose a thick sequence of Triassic Nikolai basalts that is underlain by several mafic‐ultramafic complexes, the largest and best exposed being the Fish Lake and Tangle (FL‐T) mafic‐ultramafic sills that flank the Amphitheater Mountains synform. Three‐dimensional (3‐D) modeling of gravity and magnetic...
The stratigraphic filter and bias in measurement of geologic rates
R. Schumer, D. Jerolmack, Brandon McElroy
2011, Geophysical Research Letters (38)
Erosion and deposition rates estimated from the stratigraphic record frequently exhibit a power‐law dependence on measurement interval. This dependence can result from a power‐law distribution of stratigraphic hiatuses. By representing the stratigraphic filter as a stochastic process called a reverse ascending ladder, we describe a likely origin of power‐law hiatuses,...
Whole-edifice ice volume change A.D. 1970 to 2007/2008 at Mount Rainier, Washington, based on LiDAR surveying
T. W. Sisson, J.E. Robinson, D.D. Swinney
2011, Geology (39) 639-642
Net changes in thickness and volume of glacial ice and perennial snow at Mount Rainier, Washington State, have been mapped over the entire edifice by differencing between a highresolution LiDAR (light detection and ranging) topographic survey of September-October 2007/2008 and the 10 m lateral resolution U.S. Geological Survey digital elevation...
Pore networks in continental and marine mudstones: Characteristics and controls on sealing behavior
J.E. Heath, T.A. Dewers, B.J.O.L. McPherson, R. Petrusak, T.C. Chidsey, A.J. Rinehart, P.S. Mozley
2011, Geosphere (7) 429-454
Mudstone pore networks are strong modifiers of sedimentary basin fluid dynamics and have a critical role in the distribution of hydrocarbons and containment of injected fluids. Using core samples from continental and marine mudstones, we investigate properties of pore types and networks from a variety of geologic environments, together with...
Spatial modeling for groundwater arsenic levels in North Carolina
D. Kim, M.L. Miranda, J. Tootoo, P. Bradley, A.E. Gelfand
2011, Environmental Science & Technology (45) 4824-4831
To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized...
Characterizing land surface change and levee stability in the Sacramento-San Joaquin Delta using UAVSAR radar imagery
C. Jones, G. Bawden, S. Deverel, J. Dudas, S. Hensley
2011, Conference Paper, International Geoscience and Remote Sensing Symposium (IGARSS)
The islands of the Sacramento-San Joaquin Delta have been subject to subsidence since they were first reclaimed from the estuary marshlands starting over 100 years ago, with most of the land currently lying below mean sea level. This area, which is the primary water resource of the state of California,...
Modal-pushover-based ground-motion scaling procedure
Erol Kalkan, Anil K. Chopra
2011, Journal of Structural Engineering (137) 298-310
Earthquake engineering is increasingly using nonlinear response history analysis (RHA) to demonstrate the performance of structures. This rigorous method of analysis requires selection and scaling of ground motions appropriate to design hazard levels. This paper presents a modal-pushover-based scaling (MPS) procedure to scale ground motions for use in a nonlinear...
Positive feedback and momentum growth during debris-flow entrainment of wet bed sediment
Richard M. Iverson, Mark E. Reid, Matthew Logan, Richard G. Lahusen, Jonathan W. Godt, Julia P. Griswold
2011, Nature Geoscience (4) 116-121
Debris flows typically occur when intense rainfall or snowmelt triggers landslides or extensive erosion on steep, debris-mantled slopes. The flows can then grow dramatically in size and speed as they entrain material from their beds and banks, but the mechanism of this growth is unclear. Indeed, momentum conservation implies that...
Increased fitness of rice plants to abiotic stress via habitat adapted symbiosis: A strategy for mitigating impacts of climate change
R. S. Redman, Y.-O. Kim, C.J.D.A. Woodward, C. Greer, L. Espino, S.L. Doty, R. J. Rodriguez
2011, PLoS ONE (6)
Climate change and catastrophic events have contributed to rice shortages in several regions due to decreased water availability and soil salinization. Although not adapted to salt or drought stress, two commercial rice varieties achieved tolerance to these stresses by colonizing them with Class 2 fungal endophytes isolated from plants growing...
Adaptive finite volume methods with well-balanced Riemann solvers for modeling floods in rugged terrain: Application to the Malpasset dam-break flood (France, 1959)
D.L. George
2011, International Journal for Numerical Methods in Fluids (66) 1000-1018
The simulation of advancing flood waves over rugged topography, by solving the shallow-water equations with well-balanced high-resolution finite volume methods and block-structured dynamic adaptive mesh refinement (AMR), is described and validated in this paper. The efficiency of block-structured AMR makes large-scale problems tractable, and allows the use of accurate and...
Geology and petroleum potential of the Lincoln Sea Basin, offshore North Greenland
K. Sorensen, D. Gautier, Janet K. Pitman, H. Ruth Jackson, T. Dahl-Jensen
2011, Geological Society Memoir (35) 673-684
A seismic refraction line crossing the Lincoln Sea was acquired in 2006. It proves the existence of a deep sedimentary basin underlying the Lincoln Sea. This basin appears to be comparable in width and depth to the Sverdrup Basin of the Canadian Arctic Islands. The stratigraphy of the Lincoln Sea...
