Unique geologic insights from "non-unique" gravity and magnetic interpretation
R. W. Saltus, R.J. Blakely
2011, GSA Today (21) 4-11
Interpretation of gravity and magnetic anomalies is mathematically non-unique because multiple theoretical solutions are always possible. The rigorous mathematical label of "nonuniqueness" can lead to the erroneous impression that no single interpretation is better in a geologic sense than any other. The purpose of this article is to present a...
Simulating the potential effects of climate change in two Colorado basins and at two Colorado ski areas
William Battaglin, Lauren E. Hay, Steve Markstrom
2011, Earth Interactions (15) 1-23
The mountainous areas of Colorado are used for tourism and recreation, and they provide water storage and supply for municipalities, industries, and agriculture. Recent studies suggest that water supply and tourist industries such as skiing are at risk from climate change. In this study, a distributed-parameter watershed model, the Precipitation-Runoff...
Distinguishing between stress-induced and structural anisotropy at Mount Ruapehu volcano, New Zealand
J. H. Johnson, M.K. Savage, J. Townend
2011, Journal of Geophysical Research B: Solid Earth (116)
We have created a benchmark of spatial variations in shear wave anisotropy around Mount Ruapehu, New Zealand, against which to measure future temporal changes. Anisotropy in the crust is often assumed to be caused by stress-aligned microcracks, and the polarization of the...
Monitoring direct and indirect climate effects on whitebark pine ecosystems at Crater Lake National park
S.B. Smith, D.C. Odion, D.A. Sarr, K.M. Irvine
2011, Park Science (28)
Whitebark pine (Pinus albicaulis) is the distinctive, often stunted, and picturesque tree line species in the American West. As a result of climate change, mountain pine beetles (Dendroctonus ponderosae) have moved up in elevation, adding to nonnative blister rust (Cronartium ribicola) disease as a major cause of mortality in whitebark...
Water and heat transport in boreal soils: Implications for soil response to climate change
Z. Fan, J. C. Neff, J.W. Harden, T. Zhang, H. Veldhuis, C.I. Czimczik, G.C. Winston, J. A. O'Donnell
2011, Science of the Total Environment (409) 1836-1842
Soil water content strongly affects permafrost dynamics by changing the soil thermal properties. However, the movement of liquid water, which plays an important role in the heat transport of temperate soils, has been under-represented in boreal studies. Two different heat transport models with and without convective heat transport were compared...
A predator-prey model with a holling type I functional response including a predator mutual interference
G. Seo, D.L. DeAngelis
2011, Journal of Nonlinear Science (21) 811-833
The most widely used functional response in describing predator-prey relationships is the Holling type II functional response, where per capita predation is a smooth, increasing, and saturating function of prey density. Beddington and DeAngelis modified the Holling type II response to include interference of predators that increases with predator density....
Modeling hydrologic and geomorphic hazards across post-fire landscapes using a self-organizing map approach
Michael J. Friedel
2011, Environmental Modelling and Software (26) 1660-1674
Few studies attempt to model the range of possible post-fire hydrologic and geomorphic hazards because of the sparseness of data and the coupled, nonlinear, spatial, and temporal relationships among landscape variables. In this study, a type of unsupervised artificial neural network, called a self-organized map (SOM), is trained using data...
Second California Assessment: Integrated climate change impacts assessment of natural and managed systems. Guest editorial
G. Franco, D.R. Cayan, S. Moser, M. Hanemann, M. A. Jones
2011, Climatic Change (109) 1-19
Since 2006 the scientific community in California, in cooperation with resource managers, has been conducting periodic statewide studies about the potential impacts of climate change on natural and managed systems. This Special Issue is a compilation of revised papers that originate from the most recent assessment that concluded in 2009....
Integration of paleoseismic data from multiple sites to develop an objective earthquake chronology: Application to the Weber segment of the Wasatch fault zone, Utah
C. B. DuRoss, S. F. Personius, A. J. Crone, S.S. Olig, W.R. Lund
2011, Bulletin of the Seismological Society of America (101) 2765-2781
We present a method to evaluate and integrate paleoseismic data from multiple sites into a single, objective measure of earthquake timing and recurrence on discrete segments of active faults. We apply this method to the Weber segment (WS) of the Wasatch fault zone using data from four fault-trench studies completed...
Evidence for low-grade metamorphism, hydrothermal alteration, and diagenesis on Mars from phyllosilicate mineral assemblages
Bethany L. Ehlmann, John F Mustard, Roger N. Clark, Gregg A. Swayze, Scott L. Murchie
2011, Clays and Clay Minerals (59) 359-377
The enhanced spatial and spectral resolution provided by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on the Mars Reconnaissance Orbiter (MRO) has led to the discovery of numerous hydrated silicate minerals on Mars, particularly in the ancient, cratered crust comprising the southern highlands. Phases recently identified using visible/near-infrared spectra...
Evaluation of Nobuto filter paper strips for the detection of avian influenza virus antibody in waterfowl
Robert J. Dusek, Jeffrey S. Hall, Sean W. Nashold, Joshua L. Teslaa, Hon S. Ip
2011, Avian Diseases (55) 674-676
The utility of using Nobuto paper strips for the detection of avian influenza antibodies was examined in mallards (Anas platyrhynchos) experimentally infected with low pathogenic avian influenza viruses. Blood was collected 2 wk after infection and was preserved either as serum or whole blood absorbed onto Nobuto strips. Analysis of...
Methodology to assess water presence on speleothems during periods of low precipitation, with implications for recharge sources - Kartchner Caverns, Arizona
Kyle W. Blasch
2011, Journal of Cave and Karst Studies (73) 63-74
Beginning in January 2005, recharge processes and the presence of water on speleothems were monitored in Kartchner Caverns during a 44-month period when annual rainfall rates were 6 to 18 percent below the long-term mean. Electrical-resistance sensors designed to detect the presence of water were used to identify ephemeral streamflow...
Ontogenetic and diel variation in stream habitat use by brook trout (Salvelinus fontinalis) in a headwater stream
J. H. Johnson, R. M. Ross, D. S. Dropkin, Lori A. Redell
2011, Journal of Freshwater Ecology (26) 143-152
Although considerable information exists on habitat use by stream salmonids, only a small portion has quantitatively examined diurnal and nocturnal habitat variation. We examined diel variation in habitat use by age-0 and age-1+ brook trout (Salvelinus fontinalis) during summer and autumn in a headwater stream in northern Pennsylvania. Habitat variables...
Self-potential investigations of a gravel bar in a restored river corridor
N. Linde, J. Doetsch, D. Jougnot, O. Genoni, Y. Durst, B. J. Minsley, T. Vogt, N. Pasquale, J. Luster
2011, Hydrology and Earth System Sciences (15) 729-742
Self-potentials (SP) are sensitive to water fluxes and concentration gradients in both saturated and unsaturated geological media, but quantitative interpretations of SP field data may often be hindered by the superposition of different source contributions and time-varying electrode potentials. Self-potential mapping and close to two months of SP monitoring on...
Scattered P'P' waves observed at short distances
Paul S. Earle, Sebastian Rost, Peter M. Shearer, Christine Thomas
2011, Bulletin of the Seismological Society of America (101) 2843-2854
We detect previously unreported 1 Hz scattered waves at epicentral distances between 30° and 50° and at times between 2300 and 2450 s after the earthquake origin. These waves likely result from off-azimuth scattering of PKPbc to PKPbc in the upper mantle and crust and provide a new tool for...
Nest success of snowy plovers (Charadrius nivosus) in the Southern high plains of Texas
S.T. Saalfeld, Warren C. Conway, D.A. Haukos, W.P. Johnson
2011, Waterbirds (34) 389-399
Snowy Plovers (Charadrius nivosus) nesting on edges of saline lakes within the Southern High Plains (SHP) of Texas are threatened by habitat degradation due to reduced artesian spring flow, making many saline lakes unsuitable for nesting and migrating shorebirds. Factors influencing nest success were evaluated, current nest success estimates in...
Pore morphology effect in microlog for porosity prediction in a mature field
W.J. Teh, G.P. Willhite, J.H. Doveton, J.S. Tsau
2011, Conference Paper, SPE Eastern Regional Meeting
In an matured field, developed during the 1950s, no porosity logs were available from sources other than invaded zone resistivity Rxo . The microresistivity porosity is calibrated with the core porosity to yield an accurate estimate of the porosity. However, the procedure of calibrating the porosity with Rxo for a...
Shortnose sturgeon use small coastal rivers: The importance of habitat connectivity
Gayle B. Zydlewski, M.T. Kinnison, P.E. Dionne, Joseph D. Zydlewski, Gail S. Wippelhauser
2011, Journal of Applied Ichthyology (27) 41-44
Contrary to conventional wisdom for shortnose sturgeon (Acipenser brevirostrum), we document shortnose sturgeon use of habitats beyond large rivers. Telemetry data from 2008 to 2010 in the Gulf of Maine demonstrates that adult shortnose sturgeon (up to 70%) frequently move between Maine’s two largest rivers, the Kennebec and Penobscot Rivers....
Mapping and monitoring Louisiana's mangroves in the aftermath of the 2010 Gulf of Mexico Oil spill
S. Giri, J. Long, L. Tieszen
2011, Journal of Coastal Research (27) 1059-1064
Information regarding the present condition, historical status, and dynamics of mangrove forests is needed to study the impacts of the Gulf of Mexico oil spill and other stressors affecting mangrove ecosystems. Such information is unavailable for Louisiana at sufficient spatial and thematic detail. We prepared mangrove forest distribution maps of...
Episodic soil succession on basaltic lava fields in a cool, dry environment
K.L. Vaughan, P.A. McDaniel, W.M. Phillips
2011, Soil Science Society of America Journal (75) 1462-1470
Holocene- to late Pleistocene-aged lava flows at Craters of the Moon National Monument and Preserve provide an ideal setting to examine the early stages of soil formation under cool, dry conditions. Transects were used to characterize the amount and nature of soil cover on across basaltic lava flows ranging in...
Migration delays caused by anthropogenic barriers: Modeling dams, temperature, and success of migrating salmon smolts
E.A. Marschall, M. E. Mather, D.L. Parrish, G.W. Allison, J.R. McMenemy
2011, Ecological Applications (21) 3014-3031
Disruption to migration is a growing problem for conservation and restoration of animal populations. Anthropogenic barriers along migration paths can delay or prolong migrations, which may result in a mismatch with migration-timing adaptations. To understand the interaction of dams (as barriers along a migration path), seasonally changing environmental conditions, timing...
An open-water electrical geophysical tool for mapping sub-seafloor heavy placer minerals in 3D and migrating hydrocarbon plumes in 4D
J. Wynn, M. Williamson, S. Urquhart, J. Fleming
2011, Conference Paper, OCEANS'11 - MTS/IEEE Kona, Program Book
A towed-streamer technology has been developed for mapping placer heavy minerals and dispersed hydrocarbon plumes in the open ocean. The approach uses induced polarization (IP), an electrical measurement that encompasses several different surface-reactive capacitive and electrochemical phenomena, and thus is ideally suited for mapping dispersed or disseminated targets. The application...
Aeolian nutrient fluxes following wildfire in sagebrush steppe: Implications for soil carbon storage
N.J. Hasselquist, M.J. Germino, J.B. Sankey, L.J. Ingram, N.F. Glenn
2011, Biogeosciences (8) 3649-3659
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 ecosystem...
USGS "Did You Feel It?" internet-based macroseismic intensity maps
D.J. Wald, V. Quitoriano, B. Worden, M. Hopper, J. W. Dewey
2011, Annals of Geophysics (54) 688-707
The U.S. Geological Survey (USGS) "Did You Feel It?" (DYFI) system is an automated approach for rapidly collecting macroseismic intensity data from Internet users' shaking and damage reports and generating intensity maps immediately following earthquakes; it has been operating for over a decade (1999-2011). DYFI-based intensity maps made rapidly available...
From agricultural intensification to conservation: Sediment transport in the Raccoon River, Iowa, 1916-2009
C.S. Jones, K. E. Schilling
2011, Journal of Environmental Quality (40) 1911-1923
Fluvial sediment is a ubiquitous pollutant that negatively aff ects surface water quality and municipal water supply treatment. As part of its routine water supply monitoring, the Des Moines Water Works (DMWW) has been measuring turbidity daily in the Raccoon River since 1916. For this study, we calibrated daily turbidity...
