Testing small-aperture array analysis on well-located earthquakes, and application to the location of deep tremor
Rocca M. La, D. Galluzzo, S. Malone, W. McCausland, G. Saccorotti, Pezzo E. Del
2008, Bulletin of the Seismological Society of America (98) 620-635
We have here analyzed local and regional earthquakes using array techniques with the double aim of quantifying the errors associated with the estimation of propagation parameters of seismic signals and testing the suitability of a probabilistic location method for the analysis of nonimpulsive signals. We have applied the zero-lag cross-correlation...
Devonian brachiopods of southwesternmost laurentia: Biogeographic affinities and tectonic significance
A. J. Boucot, Forrest G. Poole, R. Amaya-Martinez, A. G. Harris, Charles Sandberg, William R. Page
2008, Special Paper of the Geological Society of America 77-97
Three brachiopod faunas discussed herein record different depositional and tectonic settings along the southwestern margin of Laurentia (North America) during Devonian time. Depositional settings include inner continental shelf (Cerros de Los Murcielagos), medial continental shelf (Rancho Placeritos), and offshelf continental rise (Rancho Los Chinos). Ages of Devonian brachiopod faunas include...
Evaluating sampling designs by computer simulation: A case study with the Missouri bladderpod
L.W. Morrison, D. R. Smith, C. Young, D.W. Nichols
2008, Population Ecology (50) 417-425
To effectively manage rare populations, accurate monitoring data are critical. Yet many monitoring programs are initiated without careful consideration of whether chosen sampling designs will provide accurate estimates of population parameters. Obtaining accurate estimates is especially difficult when natural variability is high, or limited budgets determine that only a small...
Anatomy of the Chesapeake Bay impact structure revealed by seismic imaging, Delmarva Peninsula, Virginia, USA
R. D. Catchings, D.S. Powars, G. S. Gohn, J. Wright Horton Jr., M. R. Goldman, J.A. Hole
2008, Journal of Geophysical Research B: Solid Earth (113)
A 30-km-long, radial seismic reflection and refraction survey completed across the northern part of the late Eocene Chesapeake Bay impact structure (CBIS) on the Delmarva Peninsula, Virginia, USA, confirms that the CBIS is a complex central-peak crater. We used a tomographic P wave velocity model and low-fold reflection images, constrained...
Using accelerated life testing procedures to compare the relative sensitivity of rainbow trout and the federally listed threatened bull trout to three commonly used rangeland herbicides (picloram, 2,4-D, and clopyralid)
J.F. Fairchild, A. Allert, L.S. Sappington, K.J. Nelson, J. Valle
2008, Environmental Toxicology and Chemistry (27) 623-630
We conducted 96-h static acute toxicity studies to evaluate the relative sensitivity of juveniles of the threatened bull trout (Salvelinus confluentus) and the standard cold-water surrogate rainbow trout (Onchorhyncus mykiss) to three rangeland herbicides commonly used for controlling invasive weeds in the northwestern United States. Relative species sensitivity was compared...
Identifying mangrove species and their surrounding land use and land cover classes using object-oriented approach with a lacunarity spatial measure
S.W. Myint, C.P. Giri, L. Wang, Z. Zhu, S.C. Gillete
2008, GIScience and Remote Sensing (45) 188-208
Accurate and reliable information on the spatial distribution of mangrove species is needed for a wide variety of applications, including sustainable management of mangrove forests, conservation and reserve planning, ecological and biogeographical studies, and invasive species management. Remotely sensed data have been used for such purposes with mixed results. Our...
Use of sinkhole and specific capacity distributions to assess vertical gradients in a karst aquifer
K.J. McCoy, M.D. Kozar
2008, Environmental Geology (54) 921-935
The carbonate-rock aquifer in the Great Valley, West Virginia, USA, was evaluated using a database of 687 sinkholes and 350 specific capacity tests to assess structural, lithologic, and topographic influences on the groundwater flow system. The enhanced permeability of the aquifer is characterized in part by the many sinkholes, springs,...
M-log A observations for recent large earthquakes
Thomas C. Hanks, W. H. Bakun
2008, Bulletin of the Seismological Society of America (98) 490-494
Using a magnitude (M)-log area (A) dataset augmented with seven large (M > 7.0) earthquakes occurring since Wells and Coppersmith (1994), this short note assesses the current validity of the bilinear M-log A relations for continental, strike-slip earthquakes proposed by Hanks and Bakun (2002), in particular the L-model scaling at...
Flood trends and river engineering on the Mississippi River system
N. Pinter, A.A. Jemberie, J.W.F. Remo, R.A. Heine, B.S. Ickes
2008, Geophysical Research Letters (35)
Along >4000 km of the Mississippi River system, we document that climate, land-use change, and river engineering have contributed to statistically significant increases in flooding over the past 100-150 years. Trends were tested using a database of >8 million hydrological measurements. A geospatial database of historical engineering construction was used...
Surface drift prediction in the Adriatic Sea using hyper-ensemble statistics on atmospheric, ocean and wave models: Uncertainties and probability distribution areas
M. Rixen, E. Ferreira-Coelho, R. Signell
2008, Journal of Marine Systems (69) 86-98
Despite numerous and regular improvements in underlying models, surface drift prediction in the ocean remains a challenging task because of our yet limited understanding of all processes involved. Hence, deterministic approaches to the problem are often limited by empirical assumptions on underlying physics. Multi-model hyper-ensemble forecasts, which exploit the power...
Longitudinal gradients along a reservoir cascade
L.E. Miranda, M.D. Habrat, S. Miyazono
2008, Transactions of the American Fisheries Society (137) 1851-1865
Reservoirs have traditionally been regarded as spatially independent entities rather than as longitudinal segments of a river system that are connected upstream and downstream to the river and other reservoirs. This view has frustrated advancement in reservoir science by impeding adequate organization of available information and by hindering interchanges with...
Greenland ice sheet surface temperature, melt and mass loss: 2000-06
D.K. Hall, R.S. Williams Jr., S.B. Luthcke, N.E. DiGirolamo
2008, Journal of Glaciology (54) 81-93
A daily time series of 'clear-sky' surface temperature has been compiled of the Greenland ice sheet (GIS) using 1 km resolution moderate-resolution imaging spectroradiometer (MODIS) land-surface temperature (LST) maps from 2000 to 2006. We also used mass-concentration data from the Gravity Recovery and Climate Experiment (GRACE) to study mass change...
Evaluation of MODIS NDVI and NDWI for vegetation drought monitoring using Oklahoma Mesonet soil moisture data
Yingxin Gu, E. Hunt, B. Wardlow, J.B. Basara, Jesslyn F. Brown, J. P. Verdin
2008, Geophysical Research Letters (35) 1-5
The evaluation of the relationship between satellite-derived vegetation indices (normalized difference vegetation index and normalized difference water index) and soil moisture improves our understanding of how these indices respond to soil moisture fluctuations. Soil moisture deficits are ultimately tied to drought stress on plants. The diverse terrain and climate of...
Chromium, chromium isotopes and selected trace elements, western Mojave Desert, USA
J. A. Izbicki, J.W. Ball, T.D. Bullen, S. J. Sutley
2008, Applied Geochemistry (23) 1325-1352
Chromium(VI) concentrations in excess of the California Maximum Contaminant Level (MCL) of 50 μg/L occur naturally in alkaline, oxic ground-water in alluvial aquifers in the western Mojave Desert, southern California. The highest concentrations were measured in aquifers eroded from mafic rock, but Cr(VI)...
Joint inversion of fundamental and higher mode Rayleigh waves
Y.-H. Luo, J.-H. Xia, J.-P. Liu, Q.-S. Liu
2008, Chinese Journal of Geophysics (Acta Geophysica Sinica) (51) 242-249
In this paper, we analyze the characteristics of the phase velocity of fundamental and higher mode Rayleigh waves in a six-layer earth model. The results show that fundamental mode is more sensitive to the shear velocities of shallow layers (< 7 m) and concentrated in a very narrow band (around...
An overview of methods for developing bioenergetic and life history models for rare and endangered species
J.H. Petersen, D.L. DeAngelis, C.P. Paukert
2008, Transactions of the American Fisheries Society (137) 244-253
Many fish species are at risk to some degree, and conservation efforts are planned or underway to preserve sensitive populations. For many imperiled species, models could serve as useful tools for researchers and managers as they seek to understand individual growth, quantify predator-prey dynamics, and identify critical sources of mortality....
Influence of dams on river-floodplain dynamics in the Elwha River, Washington
K.K. Kloehn, T.J. Beechie, S.A. Morley, H.J. Coe, J.J. Duda
2008, Northwest Science (82) 224-235
The Elwha dam removal project presents an ideal opportunity to study how historic reduction and subsequent restoration of sediment supply alter river-floodplain dynamics in a large, forested river floodplain. We used remote sensing and onsite data collection to establish a historical record of floodplain dynamics and a baseline of current...
Demography and movement in a relocated population of Oregon Spotted Frogs (Rana pretiosa): Influence of season and gender
N.D. Chelgren, C.A. Pearl, M.J. Adams, J. Bowerman
2008, Copeia 742-751
We used five years of recapture data and Bayesian estimation to assess seasonal survival, movement, and growth of Oregon Spotted Frogs (Rana pretiosa) relocated into created ponds at Dilman Meadow in Oregon, USA. We evaluate hypotheses specific to the relocation and elucidate aspects of R. pretiosa life history that are...
Validation of the ASTER instrument level 1A scene geometry
H. H. Kieffer, K. F. Mullins, D. J. MacKinnon
2008, Photogrammetric Engineering and Remote Sensing (74) 289-301
An independent assessment of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument geometry was undertaken by the U.S. ASTER Team, to confirm the geometric correction parameters developed and applied to Level 1A (radiometrically and geometrically raw with correction parameters appended) ASTER data. The goal was to evaluate the...
De-convoluting mixed crude oil in Prudhoe Bay Field, North Slope, Alaska
K. E. Peters, Ramos L. Scott, J.E. Zumberge, Z. C. Valin, K. J. Bird
2008, Organic Geochemistry (39) 623-645
Seventy-four crude oil samples from the Barrow arch on the North Slope of Alaska were studied to assess the relative volumetric contributions from different source rocks to the giant Prudhoe Bay Field. We applied alternating least squares to concentration data (ALS-C) for 46 biomarkers in the range C19-C35 to de-convolute...
Natural radionuclide mobility and its influence on U-Th-Pb dating of secondary minerals from the unsaturated zone at Yucca Mountain, Nevada
L.A. Neymark, Y. V. Amelin
2008, Geochimica et Cosmochimica Acta (72) 2067-2089
Extreme U and Pb isotope variations produced by disequilibrium in decay chains of 238U and 232Th are found in calcite, opal/chalcedony, and Mn-oxides occurring as secondary mineral coatings in the unsaturated zone at Yucca Mountain, Nevada. These very slowly growing minerals (mm my-1) contain excess 206Pb and 208Pb formed from...
Comparison of remote sensing image processing techniques to identify tornado damage areas from Landsat TM data
S.W. Myint, M. Yuan, R.S. Cerveny, C.P. Giri
2008, Sensors (8) 1128-1156
Remote sensing techniques have been shown effective for large-scale damage surveys after a hazardous event in both near real-time or post-event analyses. The paper aims to compare accuracy of common imaging processing techniques to detect tornado damage tracks from Landsat TM data. We employed the direct change detection approach using...
Using demography and movement behavior to predict range expansion of the southern sea otter.
M. T. Tinker, D.F. Doak, J. A. Estes
2008, Ecological Applications (18) 1781-1794
In addition to forecasting population growth, basic demographic data combined with movement data provide a means for predicting rates of range expansion. Quantitative models of range expansion have rarely been applied to large vertebrates, although such tools could be useful for restoration and management of many threatened but recovering populations....
Aseismic slip and fault-normal strain along the central creeping section of the San Andreas fault
F. Rolandone, R. Burgmann, D.C. Agnew, I.A. Johanson, D.C. Templeton, M. A. d'Alessio, S.J. Titus, C. DeMets, B. Tikoff
2008, Geophysical Research Letters (35)
We use GPS data to measure the aseismic slip along the central San Andreas fault (CSAF) and the deformation across adjacent faults. Comparison of EDM and GPS data sets implies that, except for small-scale transients, the fault motion has been steady over the last 40 years. We add 42 new...
Dike orientations in the late jurassic independence dike swarm and implications for vertical-axis tectonic rotations in eastern California
R.F. Hopson, John W. Hillhouse, K. A. Howard
2008, Special Paper of the Geological Society of America 481-498
Analysis of the strikes of 3841 dikes in 47 domains in the 500-km-long Late Jurassic Independence dike swarm indicates a distribution that is skewed clockwise from the dominant northwest strike. Independence dike swarm azimuths tend to cluster near 325?? ?? 30??, consistent with initial subparallel intrusion along much of the...
