Evaluation of Maryland abutment scour equation through selected threshold velocity methods
S.T. Benedict
2010, Transportation Research Record 153-167
The U.S. Geological Survey, in cooperation with the Maryland State Highway Administration, used field measurements of scour to evaluate the sensitivity of the Maryland abutment scour equation to the critical (or threshold) velocity variable. Four selected methods for estimating threshold velocity were applied to the Maryland abutment scour equation, and...
Ecoregions and stream morphology in eastern Oklahoma
D. K. Splinter, D.C. Dauwalter, R. A. Marston, W.L. Fisher
2010, Geomorphology (122) 117-128
Broad-scale variables (i.e., geology, topography, climate, land use, vegetation, and soils) influence channel morphology. How and to what extent the longitudinal pattern of channel morphology is influenced by broad-scale variables is important to fluvial geomorphologists and stream ecologists. In the last couple of decades, there has been an increase in...
Debris flows resulting from glacial-lake outburst floods in tibet, China
P. Cui, C. Dang, Z. Cheng, K. Scott
2010, Physical Geography (31) 508-527
During the last 70 years of general climatic amelioration, 18 glacial-lake outburst floods (GLOFs) and related debris flows have occurred from 15 moraine-dammed lakes in Tibet, China. Catastrophic loss of life and property has occurred because of the following factors: the large volumes of water discharged, the steep gradients of...
Comment on "analysis of pumping test data for determining unconfined-aquifer parameters: Composite analysis or not?": Paper published in Hydrogeology Journal (2009) 17:1133-1147, by Hund-Der Yeh and Yen-Chen Huang
Allen F. Moench
2010, Hydrogeology Journal (18) 1975-1977
No abstract available....
Detrital zircon analysis of Mesoproterozoic and neoproterozoic metasedimentary rocks of northcentral idaho: Implications for development of the Belt-Purcell basin
R. S. Lewis, J.D. Vervoort, R. F. Burmester, P.J. Oswald
2010, Canadian Journal of Earth Sciences (47) 1383-1404
The authors analyzed detrital zircon grains from 10 metasedimentary rock samples of the Priest River complex and three other amphibolite-facies metamorphic sequences in north-central Idaho to test the previous assignment of these rocks to the Mesoproterozoic Belt-Purcell Supergroup. Zircon grains from two samples of the Prichard Formation (lower Belt) and...
Effect of imperfect detectability on adaptive and conventional sampling: Simulated sampling of freshwater mussels in the upper Mississippi River
D. R. Smith, B. R. Gray, T.J. Newton, D. Nichols
2010, Environmental Monitoring and Assessment (170) 499-507
Adaptive sampling designs are recommended where, as is typical with freshwater mussels, the outcome of interest is rare and clustered. However, the performance of adaptive designs has not been investigated when outcomes are not only rare and clustered but also imperfectly detected. We address this combination of challenges using data...
Depositional setting, petrology and chemistry of Permian coals from the Paraná Basin: 2. South Santa Catarina Coalfield, Brazil
W. Kalkreuth, M. Holz, A. Mexias, M. Balbinot, J. Levandowski, J. Willett, R. Finkelman, H. Burger
2010, International Journal of Coal Geology (84) 213-236
In Brazil economically important coal deposits occur in the southern part of the Paraná Basin, where coal seams occur in the <a title="Learn more about Permian from ScienceDirect's AI-generated Topic...
High tsunami frequency as a result of combined strike-slip faulting and coastal landslides
M.J. Hornbach, N. Braudy, R.W. Briggs, M.-H. Cormier, M.B. Davis, J.B. Diebold, N. Dieudonne, R. Douilly, C. Frohlich, S.P.S. Gulick, H. E. Johnson III, P. Mann, C. McHugh, K. Ryan-Mishkin, C.S. Prentice, L. Seeber, C.C. Sorlien, M.S. Steckler, S.J. Symithe, F. W. Taylor, J. Templeton
2010, Nature Geoscience (3) 783-788
Earthquakes on strike-slip faults can produce devastating natural hazards. However, because they consist predominantly of lateral motion, these faults are rarely associated with significant uplift or tsunami generation. And although submarine slides can generate tsunami, only a few per cent of all tsunami are believed to be triggered in this...
Geochemical and mineralogical evidence for Sahara and Sahel dust additions to Quaternary soils on Lanzarote, eastern Canary Islands, Spain
D.R. Muhs, J. Budahn, G. Skipp, J.M. Prospero, D. Patterson, E. Arthur Bettis III
2010, Terra Nova (22) 399-410
Africa is the most important source of dust in the world today, and dust storms are frequent on the nearby Canary Islands. Previous workers have inferred that the Sahara is the most important source of dust to Canary Islands soils, with little contribution from the Sahel region. Soils overlying a...
Locating non-volcanic tremor along the San Andreas Fault using a multiple array source imaging technique
T. Ryberg, C.H. Haberland, G. S. Fuis, W.L. Ellsworth, D.R. Shelly
2010, Geophysical Journal International (183) 1485-1500
Non-volcanic tremor (NVT) has been observed at several subduction zones and at the San Andreas Fault (SAF). Tremor locations are commonly derived by cross-correlating envelope-transformed seismic traces in combination with source-scanning techniques. Recently, they have also been located by using relative relocations with master events, that is low-frequency earthquakes that...
Patterns of ancestry and genetic diversity in reintroduced populations of the slimy sculpin: Implications for conservation
D.D. Huff, L.M. Miller, B. Vondracek
2010, Conservation Genetics (11) 2379-2391
Reintroductions are a common approach for preserving intraspecific biodiversity in fragmented landscapes. However, they may exacerbate the reduction in genetic diversity initially caused by population fragmentation because the effective population size of reintroduced populations is often smaller and reintroduced populations also tend to be more geographically isolated than native populations....
Holocene aggradation of the Dry Tortugas coral reef ecosystem
J. C. Brock, M. Palaseanu-Lovejoy, R.Z. Poore, A. Nayegandhi, C. W. Wright
2010, Coral Reefs (29) 857-868
Radiometric age dating of reef cores acquired at the Dry Tortugas coral reef ecosystem (DTCRE) was merged with lidar topographic mapping to examine Holocene reef development linked to spatial variation in growth and erosion under the control of sea level. Analysis of variance of lidar topography confirmed the presence of...
An evaluation of the influence of substrate on the response of juvenile freshwater mussels (fatmucket, Lampsilis siliquoidea) in acute water exposures to ammonia
J. Miao, M.C. Barnhart, Eric L. Brunson, Douglas K. Hardesty, Christopher G. Ingersoll, Ning Wang
2010, Environmental Toxicology and Chemistry (29) 2112-2116
Acute 96-h ammonia toxicity to three-month-old juvenile mussels (Lampsilis siliquoidea) was evaluated in four treatments (water-only, water-only with feeding, water and soil, and water and sand) using an exposure unit designed to maintain consistent pH and ammonia concentrations in overlying water and in pore water surrounding the substrates. Median effect...
Algal blooms and "Marine snow": Mechanisms that enhance preservation of organic carbon in ancient fine-grained sediments
Joe H.S. Macquaker, Margaret A. Keller, Sarah J. Davies
2010, Journal of Sedimentary Research (80) 934-942
Combined petrographic and geochemical methods are used to investigate the microfabrics present in thin sections prepared from representative organic carbon-rich mudstones collected from three successions (the Kimmeridge Clay Formation, the Jet Rock Member of the Whitby Mudstone Formation, and the pebble shale and Hue Shale). This study was initiated...
Natural chlorate in the environment: Application of a new IC-ESI/MS/MS method with a Cl18O3- internal standard
Balaji Rao, Paul B. Hatzinger, J.K. Bohlke, Neil C. Sturchio, Brian J. Andraski, Frank D. Eckardt, W. Andrew Jackson
2010, Environmental Science & Technology (44) 8429-8434
A new ion chromatography electrospray tandem mass spectrometry (IC-ESI/MS/MS) method has been developed for quantification and confirmation of chlorate (ClO3−) in environmental samples. The method involves the electro-chemical generation of isotopically labeled chlorate internal standard (Cl18O3−) using 18O water (H218O). The standard was added to all samples prior to analysis...
Carbon and hydrogen isotopic evidence for the origin of combustible gases in water-supply wells in north-central Pennsylvania
K. M. Revesz, K. J. Breen, A.J. Baldassare, R.C. Burruss
2010, Applied Geochemistry (25) 1845-1859
The origin of the combustible gases in groundwater from glacial-outwash and fractured-bedrock aquifers was investigated in northern Tioga County, Pennsylvania. Thermogenic methane (CH4) and ethane (C2H6) and microbial CH4 were found. Microbial CH4 is from natural in situ processes in the shale bedrock and occurs chiefly in the bedrock aquifer....
Urbanization in a great plains river: Effects on fishes and food webs
J.L. Eitzmann, C.P. Paukert
2010, River Research and Applications (26) 948-959
Spatial variation of habitat and food web structure of the fish community was investigated at three reaches in the Kansas River, USA to determine if ??13C variability and ??15N values differ longitudinally and are related to urbanization and instream habitat. Fish and macroinvertebrates were collected at three river reaches in...
Tree-ring 14C links seismic swarm to CO2 spike at Yellowstone, USA
William C. Evans, D. Bergfeld, J. P. McGeehin, J.C. King, H. Heasler
2010, Geology (38) 1075-1078
Mechanisms to explain swarms of shallow seismicity and inflation-deflation cycles at Yellowstone caldera (western United States) commonly invoke episodic escape of magma-derived brines or gases from the ductile zone, but no correlative changes in the surface efflux of magmatic constituents have ever been documented. Our analysis of individual growth rings...
A complex-systems approach to predicting effects of sea level rise and nitrogen loading on nitrogen cycling in coastal wetland ecosystems
Laurel G. Larsen, Serena Moseman, Alyson Santoro, Kristine Hopfensperger, Amy Burgin
2010, Book chapter, Eco-DAS VIII Symposium Proceedings
To effectively manage coastal ecosystems, we need an improvedunderstanding of how tidal marsh ecosystem services will respond to sea-level rise and increased nitrogen (N) loading to coastal areas. Here we review existing literature to better understand how these interacting perturbations s will likely impact N removal by tidal marshes. We...
In vitro studies evaluating leaching of mercury from mine waste calcine using simulated human body fluids
John E. Gray, Geoffrey S. Plumlee, Suzette A. Morman, Pablo L. Higueras, James G. Crock, Heather A. Lowers, Mark L. Witten
2010, Environmental Science & Technology (44) 4782-4788
In vitro bioaccessibility (IVBA) studies were carried out on samples of mercury (Hg) mine-waste calcine (roasted Hg ore) by leaching with simulated human body fluids. The objective was to estimate potential human exposure to Hg due to inhalation of airborne calcine particulates and hand-to-mouth ingestion of Hg-bearing calcines. Mine waste...
Three-dimensional benchmark for variable-density flow and transport simulation: matching semi-analytic stability modes for steady unstable convection in an inclined porous box
Clifford I. Voss, Craig T. Simmons, Neville I. Robinson
2010, Hydrogeology Journal (18) 5-23
This benchmark for three-dimensional (3D) numerical simulators of variable-density groundwater flow and solute or energy transport consists of matching simulation results with the semi-analytical solution for the transition from one steady-state convective mode to another in a porous box. Previous experimental and analytical studies of natural convective flow in an...
Sensitivity of early life stages of freshwater mussels (Unionidae) to acute and chronic toxicity of lead, cadmium, and zinc in water
Ning Wang, Christopher G. Ingersoll, Chris D. Ivey, Douglas K. Hardesty, Thomas W. May, T. Augspurger, A.D. Roberts, E. Van Genderen, M.C. Barnhart
2010, Environmental Toxicology and Chemistry (29) 2053-2063
Toxicity of lead, cadmium, or zinc to early life stages of freshwater mussels (fatmucket, Lampsilis siliquoidea; Neosho mucket, L. rafinesqueana) was evaluated in 48‐h exposures with mussel larvae (glochidia), in 96‐h exposures with newly transformed (5‐d‐old) and two‐ or six‐month‐old juvenile mussels, or in 28‐d exposures with two‐ or four‐month‐old mussels in...
Sap flux-scaled transpiration by tamarisk (Tamarix spp.) before, during and after episodic defoliation by the saltcedar leaf beetle (Diorhabda carinulata)
K. R. Hultine, P.L. Nagler, K. Morino, S.E. Bush, K.G. Burtch, P.E. Dennison, E. P. Glenn, J.R. Ehleringer
2010, Agricultural and Forest Meteorology (150) 1467-1475
The release of the saltcedar beetle (Diorhabda carinulata) has resulted in the periodic defoliation of tamarisk (Tamarix spp.) along more than 1000 river km in the upper Colorado River Basin and is expected to spread along many other river reaches throughout the upper basin, and possibly into the lower Colorado...
Molecular investigations into a globally important carbon pool: Permafrost-protected carbon in Alaskan soils
M. P. Waldrop, K.P. Wickland, Rickie White, A.A. Berhe, J.W. Harden, V.E. Romanovsky
2010, Global Change Biology (16) 2543-2554
The fate of carbon (C) contained within permafrost in boreal forest environments is an important consideration for the current and future carbon cycle as soils warm in northern latitudes. Currently, little is known about the microbiology or chemistry of permafrost soils that may affect its decomposition once soils thaw. We...
Whole-rock Pb and Sm-Nd isotopic constraints on the growth of southeastern Laurentia during Grenvillian orogenesis
C. M. Fisher, S. L. Loewy, C. F. Miller, P. Berquist, W. R. Van Schmus, R. D. Hatcher Jr., J. L. Wooden, P. D. Fullagar
2010, Geological Society of America Bulletin (122) 1646-1659
The conventional view that the basement of the southern and central Appalachians represents juvenile Mesoproterozoic crust, the final stage of growth of Laurentia prior to Grenville collision, has recently been challenged. New whole-rock Pb and Sm‑Nd isotopic data are presented from Mesoproterozoic basement in the southern and central Appalachians and...
