Distribution of sea anemones (Cnidaria, Actiniaria) in Korea analyzed by environmental clustering
H.-R. Cha, R. W. Buddemeier, D.G. Fautin, P. Sandhei
2004, Conference Paper, Hydrobiologia
Using environmental data and the geospatial clustering tools LOICZView and DISCO, we empirically tested the postulated existence and boundaries of four biogeographic regions in the southern part of the Korean peninsula. Environmental variables used included wind speed, sea surface temperature (SST), salinity, tidal amplitude, and the chlorophyll spectral signal. Our...
Re-Os sulfide geochronology of the Red Dog sediment-hosted Zn-Pb-Ag deposit, Brooks Range, Alaska
R.M. Morelli, R.A. Creaser, D. Selby, K.D. Kelley, D. L. Leach, A.R. King
2004, Economic Geology (99) 1569-1576
The Red Dog sediment-hosted deposit in the De Long Mountains of northern Alaska is the largest Zn producer in the world. Main stage mineralization is characterized by massive sulfide ore and crosscutting subvertical veins. Although the vein mineralization is clearly younger than the massive ore, the exact temporal relationship between...
Petroleum generation and migration in the Mesopotamian Basin and Zagros Fold Felt of Iraq: Results from a basin-modeling study
Janet K. Pitman, D. Steinshouer, M. D. Lewan
2004, GeoArabia (9) 41-72
A regional 3-D total petroleum-system model was developed to evaluate petroleum generation and migration histories in the Mesopotamian Basin and Zagros fold belt in Iraq. The modeling was undertaken in conjunction with Middle East petroleum assessment studies conducted by the USGS. Regional structure maps, isopach and facies maps, and thermal...
Estimation of hydraulic conductivity in an alluvial system using temperatures
G.W. Su, James Jasperse, D. Seymour, J. Constantz
2004, Ground Water (42) 890-901
Well water temperatures are often collected simultaneously with water levels; however, temperature data are generally considered only as a water quality parameter and are not utilized as an environmental tracer. In this paper, water levels and seasonal temperatures are used to estimate hydraulic conductivities in a stream-aquifer system. To demonstrate...
Use of qualitative and quantitative information in neural networks for assessing agricultural chemical contamination of domestic wells
A. Mishra, C. Ray, D.W. Kolpin
2004, Journal of Hydrologic Engineering (9) 502-511
A neural network analysis of agrichemical occurrence in groundwater was conducted using data from a pilot study of 192 small-diameter drilled and driven wells and 115 dug and bored wells in Illinois, a regional reconnaissance network of 303 wells across 12 Midwestern states, and a study of 687 domestic wells...
Field-based evaluation of semipermeable membrane devices (SPMDs) as passive air samplers of polyaromatic hydrocarbons (PAHs)
M.E. Bartkow, J.N. Huckins, J.F. Muller
2004, Atmospheric Environment (38) 5983-5990
Semipermeable membrane devices (SPMDs) have been used as passive air samplers of semivolatile organic compounds in a range of studies. However, due to a lack of calibration data for polyaromatic hydrocarbons (PAHs), SPMD data have not been used to estimate air concentrations of target PAHs. In this study, SPMDs were...
Source parameters and rupture velocities of microearthquakes in western Nagano, Japan, determined using stopping phases
K. Imanishi, M. Takeo, W.L. Ellsworth, H. Ito, T. Matsuzawa, Y. Kuwahara, Y. Iio, S. Horiuchi, S. Ohmi
2004, Bulletin of the Seismological Society of America (94) 1762-1780
We use an inversion method based on stopping phases (Imanishi and Takeo, 2002) to estimate the source dimension, ellipticity, and rupture velocity of microearthquakes and investigate the scaling relationships between source parameters. We studied 25 earthquakes, ranging in size from M 1.3 to M 2.7, that occurred between May and...
A GIS analysis of suitability for construction aggregate recycling sites using regional transportation network and population density features
G.R. Robinson Jr., K. E. Kapo
2004, Resources, Conservation and Recycling (42) 351-365
Aggregate is used in road and building construction to provide bulk, strength, support, and wear resistance. Reclaimed asphalt pavement (RAP) and reclaimed Portland cement concrete (RPCC) are abundant and available sources of recycled aggregate. In this paper, current aggregate production operations in Virginia, Maryland, and the District of Columbia are...
Volatile organic compounds in ground water from rural private wells, 1986 to 1999
M.J. Moran, W.W. Lapham, B.L. Rowe, J.S. Zogorski
2004, Journal of the American Water Resources Association (40) 1141-1157
The U.S. Geological Survey (USGS) collected or compiled data on volatile organic compounds (VOCs) in samples of untreated ground water from 1,926 rural private wells during 1986 to 1999. At least one VOC was detected in 12 percent of samples from rural private wells. Individual VOCs were not commonly detected...
Quantitative mineralogy of the Yukon River system: Changes with reach and season, and determining sediment provenance
D. D. Eberl
2004, American Mineralogist (89) 1784-1794
The mineralogy of Yukon River basin sediment has been studied by quantitative X-ray diffraction. Bed, beach, bar, and suspended sediments were analyzed using the RockJock computer program. The bed sediments were collected from the main stem and from selected tributaries during a single trip down river, from Whitehorse to the...
Probabilistic seismic hazard analysis for Sumatra, Indonesia and across the Southern Malaysian Peninsula
M.D. Petersen, J. Dewey, S. Hartzell, C. Mueller, S. Harmsen, A.D. Frankel, K. Rukstales
2004, Tectonophysics (390) 141-158
The ground motion hazard for Sumatra and the Malaysian peninsula is calculated in a probabilistic framework, using procedures developed for the US National Seismic Hazard Maps. We constructed regional earthquake source models and used standard published and modified attenuation equations to calculate peak ground acceleration at 2% and 10% probability...
Seismic hazard maps of Mexico, the Caribbean, and Central and South America
J.G. Tanner, K. M. Shedlock
2004, Tectonophysics (390) 159-175
The growth of megacities in seismically active regions around the world often includes the construction of seismically unsafe buildings and infrastructures due to an insufficient knowledge of existing seismic hazard and/or economic constraints. Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends...
Field investigation into unsaturated flow and transport in a fault: Model analyses
H.-H. Liu, R. Salve, J.-S. Wang, G.S. Bodvarsson, D. Hudson
2004, Journal of Contaminant Hydrology (74) 39-59
Results of a fault test performed in the unsaturated zone of Yucca Mountain, Nevada, were analyzed using a three-dimensional numerical model. The fault was explicitly represented as a discrete feature and the surrounding rock was treated as a dual-continuum (fracture-matrix) system. Model calibration against seepage and water-travel-velocity data suggests that...
Evaluating the source of streamwater nitrate using δ15N and δ18O in nitrate in two watersheds in New Hampshire, USA
Linda H. Pardo, Carol Kendall, Jennifer Pett-Ridge, Cecily C.Y. Chang
2004, Hydrological Processes (18) 2699-2712
The natural abundance of nitrogen and oxygen isotopes in nitrate can be a powerful tool for identifying the source of nitrate in streamwater in forested watersheds, because the two main sources of nitrate, atmospheric deposition and microbial nitrification, have distinct δ18O values. Using a simple mixing model, we estimated the...
VOCs in shallow groundwater in new residential/commercial areas of the United States
P. J. Squillace, M.J. Moran, C. V. Price
2004, Environmental Science & Technology (38) 5327-5338
The quality of shallow groundwater in urban areas was investigated by sampling 518 monitoring wells between 1996 and 2002 as part of the National Water-Quality Assessment Program of the U.S. Geological Survey. Well networks were installed primarily in new residential/commercial areas less than about 30 years old (17 studies) and...
Borehole petrophysical chemostratigraphy of Pennsylvanian black shales in the Kansas subsurface
J.H. Doveton, D. F. Merriam
2004, Chemical Geology (206) 249-258
Pennsylvanian black shales in Kansas have been studied on outcrop for decades as the core unit of the classic Midcontinent cyclothem. These shales appear to be highstand condensed sections in the sequence stratigraphic paradigm. Nuclear log suites provide several petrophysical measurements of rock chemistry that are a useful data source...
Frequency-dependent Lg Q within the continental United States
D. Erickson, D.E. McNamara, H.M. Benz
2004, Bulletin of the Seismological Society of America (94) 1630-1643
Frequency-dependent crustal attenuation (1/Q) is determined for seven distinct physiographic/tectonic regions of the continental United States using high-quality Lg waveforms recorded on broadband stations in the frequency band 0.5 to 16 Hz. Lg attenuation is determined from time-domain amplitude measurements in one-octave frequency bands centered on the frequencies 0.75, 1.0,...
Estimating site occupancy and species detection probability parameters for terrestrial salamanders
L.L. Bailey, T.R. Simons, K. H. Pollock
2004, Ecological Applications (14) 692-702
Recent, worldwide amphibian declines have highlighted a need for more extensive and rigorous monitoring programs to document species occurrence and detect population change. Abundance estimation methods, such as mark-recapture, are often expensive and impractical for large-scale or long-term amphibian monitoring. We apply a new method to estimate proportion of area...
Prediction of nonlinear soil effects
S. Hartzell, L.F. Bonilla, R. A. Williams
2004, Bulletin of the Seismological Society of America (94) 1609-1629
Mathematical models of soil nonlinearity in common use and recently developed nonlinear codes compared to investigate the range of their predictions. We consider equivalent linear formulations with and without frequency-dependent moduli and damping ratios and nonlinear formulations for total and effective stress. Average velocity profiles to 150 m depth with...
Modeling interpopulation dispersal by banner-tailed kangaroo rats
J.L. Skvarla, J.D. Nichols, J.E. Hines, P.M. Waser
2004, Ecology (85) 2737-2746
Many metapopulation models assume rules of population connectivity that are implicitly based on what we know about within-population dispersal, but especially for vertebrates, few data exist to assess whether interpopulation dispersal is just within-population dispersal "scaled up." We extended existing multi-stratum mark-release-recapture models to incorporate the robust design, allowing us...
Emplacement mechanisms of the South Kona slide complex, Hawaii Island: Sampling and observations by remotely operated vehicle Kaiko
H. Yokose, P. W. Lipman
2004, Bulletin of Volcanology (66) 569-584
Emplacement of a giant submarine slide complex, offshore of South Kona, Hawaii Island, was investigated in 2001 by visual observation and in-situ sampling on the bench scarp and a megablock, during two dives utilizing the Remotely Operated Vehicle (ROV) Kaiko and its mother ship R/V Kairei. Topography of the bench...
Mortality sensitivity in life-stage simulation analysis: A case study of southern sea otters
L.R. Gerber, M. T. Tinker, D.F. Doak, J. A. Estes, David A. Jessup
2004, Ecological Applications (14) 1554-1565
Currently, there are no generally recognized approaches for linking detailed mortality and pathology data to population-level analyses of extinction risk. We used a combination of analytical and simulation-based analyses to examine 20 years of age- and sex-specific mortality data for southern sea otters (Enhydra lutris), and we applied results to...
Chemical and carbon isotopic composition of dissolved organic carbon in a regional confined methanogenic aquifer
R. Aravena, L.I. Wassenaar, E.C. Spiker
2004, Isotopes in Environmental and Health Studies (40) 103-114
This study demonstrates the advantage of a combined use of chemical and isotopic tools to understand the dissolved organic carbon (DOC) cycle in a regional confined methanogenic aquifer. DOC concentration and carbon isotopic data demonstrate that the soil zone is a primary carbon source of groundwater DOC in areas close...
Hazard assessment of a simulated oil spill on intertidal areas of the St. Lawrence River with SPMD-TOX
B. Thomas Johnson, J. D. Petty, J.N. Huckins, Kenneth Lee, J. Gauthier
2004, Environmental Toxicology (19) 329-335
Phytoremediation in a simulated crude oil spill was studied with a “minimalistic” approach. The SPMD-TOX paradigm—a miniature passive sorptive device to collect and concentrate chemicals and microscale tests to detect toxicity—was used to monitor over time the bioavailability and potential toxicity of an oil spill. A simulated crude oil spill...
Wrightwood and the earthquake cycle: What a long recurrence record tells us about how faults work
R. Weldon, K. Scharer, T. Fumal, G. Biasi
2004, GSA Today (14) 4-10
The concept of the earthquake cycle is so well established that one often hears statements in the popular media like, "the Big One is overdue" and "the longer it waits, the bigger it will be." Surprisingly, data to critically test the variability in recurrence intervals, rupture displacements, and relationships between...
