Channel formation by flow stripping: large-scale scour features along the Monterey East Channel and their relation to sediment waves
A. Fildani, W. R. Normark, S. Kostic, G. Parker
2006, Sedimentology (53) 1265-1287
The Monterey East system is formed by large-scale sediment waves deposited as a result of flows stripped from the deeply incised Monterey fan valley (Monterey Channel) at the apex of the Shepard Meander. The system is dissected by a linear series of steps that take the form of scour-shaped depressions...
Modeling the probability of arsenic in groundwater in New England as a tool for exposure assessment
J. D. Ayotte, B. T. Nolan, J.R. Nuckols, K.P. Cantor, G.R. Robinson Jr., D. Baris, L. Hayes, M. Karagas, W. Bress, D.T. Silverman, J.H. Lubin
2006, Environmental Science & Technology (40) 3578-3585
We developed a process-based model to predict the probability of arsenic exceeding 5 ??g/L in drinking water wells in New England bedrock aquifers. The model is being used for exposure assessment in an epidemiologic study of bladder cancer. One important study hypothesis that may explain increased bladder cancer risk is...
Modeling and validation of a 3D velocity structure for the Santa Clara Valley, California, for seismic-wave simulations
S. Hartzell, S. Harmsen, R. A. Williams, D. Carver, A. Frankel, G. Choy, P.-C. Liu, R.C. Jachens, T.M. Brocher, C. M. Wentworth
2006, Bulletin of the Seismological Society of America (96) 1851-1881
A 3D seismic velocity and attenuation model is developed for Santa Clara Valley, California, and its surrounding uplands to predict ground motions from scenario earthquakes. The model is developed using a variety of geologic and geophysical data. Our starting point is a 3D geologic model developed primarily from geologic mapping...
Modeling regional initiation of rainfall-induced shallow landslides in the eastern Umbria Region of central Italy
D. Salciarini, J. W. Godt, W. Z. Savage, P. Conversini, R.L. Baum, J. A. Michael
2006, Landslides (3) 181-194
We model the rainfall-induced initiation of shallow landslides over a broad region using a deterministic approach, the Transient Rainfall Infiltration and Grid-based Slope-stability (TRIGRS) model that couples an infinite-slope stability analysis with a one-dimensional analytical solution for transient pore pressure response to rainfall infiltration. This model permits the evaluation of...
Homogeneity of small-scale earthquake faulting, stress, and fault strength
J.L. Hardebeck
2006, Bulletin of the Seismological Society of America (96) 1675-1688
Small-scale faulting at seismogenic depths in the crust appears to be more homogeneous than previously thought. I study three new high-quality focal-mechanism datasets of small (M < ??? 3) earthquakes in southern California, the east San Francisco Bay, and the aftershock sequence of the 1989 Loma Prieta earthquake. I quantify...
Bluff evolution along coastal drumlins: Boston Harbor Islands, Massachusetts
E. A. Himmelstoss, D. M. FitzGerald, P.S. Rosen, J.R. Allen
2006, Journal of Coastal Research (22) 1230-1240
A series of partially drowned drumlins forms the backbone of the inner islands within Boston Harbor. The shoreline of these rounded glacial deposits is composed of actively retreating bluffs formed by continual wave attack. Comparisons of bluffs reveal variability in their height and lateral extent, as well as in the...
Evaluating the relative contributions of hydroperiod and soil fertility on growth of south Florida mangroves
K. W. Krauss, T.W. Doyle, R.R. Twilley, V. H. Rivera-Monroy, J.K. Sullivan
2006, Hydrobiologia (569) 311-324
Low and high water periods create contrasting challenges for trees inhabiting periodically flooded wetlands. Low to moderate flood durations and frequencies may bring nutrient subsidies, while greater hydroperiods can be energetically stressful because of oxygen deficiency. We tested the hypothesis that hydroperiod affects the growth of mangrove seedlings and saplings...
Multidecadal climate variability of global lands and oceans
G.J. McCabe, M.A. Palecki
2006, International Journal of Climatology (26) 849-865
Principal components analysis (PCA) and singular value decomposition (SVD) are used to identify the primary modes of decadal and multidecadal variability in annual global Palmer Drought Severity Index (PDSI) values and sea-surface temperature (SSTs). The PDSI and SST data for 1925-2003 were detrended and smoothed (with a 10-year moving average)...
Influence of deflection on a fold-to-fault progression: field evidence from near Marietta, South Carolina
C.W. Clendenin, J.M. Garihan
2006, Journal of Structural Geology (28) 1316-1326
Four periods of deformation (D1-D4) are recognized in the Lion Park Road borrow pit near Marietta, South Carolina. Although each period is characterized by distinct structures, D3 produced two structural styles (D3a, D3b) resulting from layer-parallel shortening. D3a is characterized by detachment folding at the tip of an underlying thrust....
Satellite-derived, melt-season surface temperature of the Greenland Ice Sheet (2000-2005) and its relationship to mass balance
D.K. Hall, R.S. Williams Jr., K.A. Casey, N.E. DiGirolamo, Z. Wan
2006, Geophysical Research Letters (33)
Mean, clear-sky surface temperature of the Greenland Ice Sheet was measured for each melt season from 2000 to 2005 using Moderate-Resolution Imaging Spectroradiometer (MODIS)–derived land-surface temperature (LST) data-product maps. During the period of most-active melt, the mean, clear-sky surface temperature of the ice sheet was highest in 2002 (−8.29 ±...
Effect of dispersal at range edges on the structure of species ranges
V. Bahn, R.J. O’Connor, W.B. Krohn
2006, Oikos (115) 89-96
Range edges are of particular interest to ecology because they hold key insights into the limits of the realized niche and associated population dynamics. A recent feature of Oikos summarized the state of the art on range edge ecology. While the typical question is what causes range edges, another important...
Nest success of mountain plovers relative to anthropogenic edges in eastern Colorado
C.W. Mettenbrink, V.J. Dreitz, F.L. Knopf
2006, Southwestern Naturalist (51) 191-196
We monitored nest success of mountain plovers (Charadrius montanus) relative to distance from the nearest anthropogenic edges, such as fence lines, roads, and perimeters of crop fields, in 2003 and 2004. We located and observed 163 mountain plover nests in eastern Colorado (USA). At least one egg hatched in 81...
A landscape-scale model of yellow-billed loon (Gavia adamsii) habitat preferences in northern alaska
Susan L. Earnst, Robert Platte, Laura Bond
2006, Hydrobiologia (567) 227-236
We modeled yellow-billed loon (Gavia adamsii) habitat preferences in a 23,500 km2 area of northern Alaska using intensive aerial surveys and landscape-scale habitat descriptors. Of the 757 lakes censused, yellow-billed loons occupied 15% and Pacific loons (G. pacifica) 42%. Lake area, depth, proportion of shoreline in aquatic vegetation,...
Modeling effects of multinode wells on solute transport
Leonard F. Konikow, G.Z. Hornberger
2006, Ground Water (44) 648-660
Long-screen wells or long open boreholes with intraborehole flow potentially provide pathways for contaminants to move from one location to another in a ground water flow system. Such wells also can perturb a flow field so that the well will not provide water samples that are representative of ground water...
Modeling the transport and inactivation of E. coli and enterococci in the near-shore region of Lake Michigan
L. Liu, M.S. Phanikumar, S.L. Molloy, R.L. Whitman, D.A. Shively, M.B. Nevers, D.J. Schwab, J.B. Rose
2006, Environmental Science & Technology (40) 5022-5028
To investigate the transport and fate of fecal pollution at Great Lakes beaches and the health risks associated with swimming, the near-shore waters of Lake Michigan and two tributaries discharging into it were examined for bacterial indicators of human fecal pollution. The enterococcus human fecal pollution marker, which targets a...
Mountain hydrology of the western United States
Roger C. Bales, Noah P. Molotch, Thomas H. Painter, Michael D. Dettinger, Robert Rice, Jeff Dozier
2006, Water Resources Research (42)
Climate change and climate variability, population growth, and land use change drive the need for new hydrologic knowledge and understanding. In the mountainous West and other similar areas worldwide, three pressing hydrologic needs stand out: first, to better understand the processes controlling the partitioning of energy and water fluxes within...
Relative contributions of transient and steady state infiltration during ephemeral streamflow
Kyle W. Blasch, Ty P.A. Ferré, John P. Hoffmann, John B. Fleming
2006, Water Resources Research (42)
Simulations of infiltration during three ephemeral streamflow events in a coarse‐grained alluvial channel overlying a less permeable basin‐fill layer were conducted to determine the relative contribution of transient infiltration at the onset of streamflow to cumulative infiltration for the event. Water content, temperature, and piezometric measurements from 2.5‐m vertical profiles...
Simulating the influences of various fire regimes on caribou winter habitat
T. Scott Rupp, Mark Olson, Layne G. Adams, Bruce W. Dale, Kyle Joly, Jonathan Henkelman, William B. Collins, Anthony M. Starfield
2006, Ecological Applications (16) 1730-1743
Caribou are an integral component of high‐latitude ecosystems and represent a major subsistence food source for many northern people. The availability and quality of winter habitat is critical to sustain these caribou populations. Caribou commonly use older spruce woodlands with adequate terrestrial lichen, a preferred winter forage, in the understory....
Foraging patterns and prey selection in an increasing and expanding sea otter population
K.L. Laidre, R.J. Jameson
2006, Journal of Mammalogy (87) 799-807
Focal observations of sea otter (Enhydra lutris kenyoni) foraging patterns and prey selection were collected in coastal Washington between 1993 and 1999. Records consisted of 13,847 individual dives from 841 feeding bouts ranging from 1 min to >4 h. Average dive time was 55 s ?? 0.9 SE and average...
Evaluating redband trout habitat in sagebrush desert basins in southwestern Idaho
B.W. Zoellick, B.S. Cade
2006, North American Journal of Fisheries Management (26) 268-281
We estimated abundance quantiles of redband trout Oncorhynchus mykiss gairdneri relative to five site-specific habitat variables (stream shading, bank cover, bank stability, fine sediment in the stream substrate, and cover for adults) and one landscape variable (distance from stream headwaters) on 30 streams in southwestern Idaho during 1993–1998. In addition,...
National Institute of Invasive Species Science (NIISS)
Tom Stohlgren
2006, Fact Sheet 2006-3036
The National Institute of Invasive Species Science (www.NIISS.org) is a consortium of governmental and nongovernmental partners, led by the U.S. Geological Survey (USGS), whose aim is to provide reliable information and advanced decision support tools for documenting, understanding, predicting, assessing, and addressing the threat of invasive species in the United...
Comparison of trace element concentrations in livers of diseased, emaciated and non-diseased southern sea otters from the California coast
K. Kannan, T. Agusa, E. Perrotta, N. J. Thomas, S. Tanabe
2006, Chemosphere (65) 2160-2167
Infectious diseases have been implicated as a cause of high rates of adult mortality in southern sea otters. Exposure to environmental contaminants can compromise the immuno-competence of animals, predisposing them to infectious diseases. In addition to organic pollutants, certain trace elements can modulate the immune system in marine mammals. Nevertheless,...
Numerical modeling of magnetic moments for UXO applications
V. Sanchez, Y. Li, M. Nabighian, D. Wright
2006, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
The surface magnetic anomaly observed in UXO clearance is mainly dipolar and, consequently, the dipole is the only magnetic moment regularly recovered in UXO applications. The dipole moment contains information about intensity of magnetization but lacks information about shape. In contrast, higher-order moments, such as quadrupole and octupole, encode asymmetry...
Adequacy of selected evapotranspiration approximations for hydrologic simulation
D. M. Sumner
2006, Journal of the American Water Resources Association (42) 699-711
Evapotranspiration (ET) approximations, usually based on computed potential ET (PET) and diverse PET-to-ET conceptualizations, are routinely used in hydrologic analyses. This study presents an approach to incorporate measured (actual) ET data, increasingly available using micrometeorological methods, to define the adequacy of ET approximations for hydrologic simulation. The approach is demonstrated...
Cenozoic tectonic evolution of the basin and range province in northwestern Nevada
J.P. Colgan, T.A. Dumitru, P.W. Reiners, J. L. Wooden, E. L. Miller
2006, American Journal of Science (306) 616-654
A regional synthesis of new and existing geologic and thermochronologic data document late Cretaceous - early Cenozoic regional erosion, Oligocene - Miocene volcanism, and subsequent late Miocene extension of the Basin and Range Province in northwestern Nevada and northeastern California. Across an ???220-km-wide region between the Santa Rosa and Warner...
