Maturation and fecundity of a stock-enhanced population of striped bass in the Savannah River Estuary, U.S.A.
T.A. Will, T.R. Reinert, Cecil A. Jennings
2002, Journal of Fish Biology (60) 532-544
The striped bass Morone saxatilis population in the Savannah River (south-eastern U.S.A.) collapsed in the 1980s, and recent efforts to restore the population have resulted in increased catch-per-unit-effort (CPUE) of striped bass in the Savannah River Estuary (SRE). The abundance of eggs and larvae, however, remain well below historic levels....
Deformation associated with the 1997 eruption of Okmok volcano, Alaska
Dorte Mann, Jeffrey T. Freymueller, Z. Lu
2002, Journal of Geophysical Research B: Solid Earth (107) ETG 7-1-ETG 7-12
Okmok volcano, located on Umnak Island in the Aleutian chain, Alaska, is the most eruptive caldera system in North America in historic time. Its most recent eruption occurred in 1997. Synthetic aperture radar interferometry shows deflation of the caldera center of up to 140 cm during this time, preceded and...
Transport and fate of nitrate in a glacial outwash aquifer in relation to ground water age, land use practices, and redox processes
Larry J. Puckett, Timothy K. Cowdery
2002, Journal of Environmental Quality (31) 782-796
A combination of ground water modeling, chemical and dissolved gas analyses, and chlorofluorocarbon age dating of water was used to determine the relation between changes in agricultural practices, and NO−3 concentrations in ground water of a glacial outwash aquifer in west-central Minnesota. The results revealed a redox zonation throughout the saturated...
The 1999 Mw 7.1 Hector Mine, California, earthquake: A test of the stress shadow hypothesis?
R.A. Harris, R.W. Simpson
2002, Bulletin of the Seismological Society of America (92) 1497-1512
We test the stress shadow hypothesis for large earthquake interactions by examining the relationship between two large earthquakes that occurred in the Mojave Desert of southern California, the 1992 Mw 7.3 Landers and 1999 Mw 7.1 Hector Mine earthquakes. We want to determine if the 1999 Hector Mine earthquake occurred...
Diffusion model validation and interpretation of stable isotopes in river and lake ice
M.G. Ferrick, D.J. Calkins, N.M. Perron, J.H. Cragin, C. Kendall
2002, Hydrological Processes (16) 851-872
The stable isotope stratigraphy of river- and lake-ice archives winter hydroclimatic conditions, and can potentially be used to identify changing water sources or to provide important insights into ice formation processes and growth rates. However, accurate interpretations rely on known isotopic fractionation during ice growth. A one-dimensional diffusion model of...
Transient stress-coupling between the 1992 Landers and 1999 Hector Mine, California, earthquakes
Timothy Masterlark, H.F. Wang
2002, Bulletin of the Seismological Society of America (92) 1470-1486
A three-dimensional finite-element model (FEM) of the Mojave block region in southern California is constructed to investigate transient stress-coupling between the 1992 Landers and 1999 Hector Mine earthquakes. The FEM simulates a poroelastic upper-crust layer coupled to a viscoelastic lower-crust layer, which is decoupled from the upper mantle. FEM predictions...
Dynamic interpretation of slug tests in highly permeable aquifers
Brian R. Zurbuchen, Vitaly A. Zlotnik, James J. Butler Jr.
2002, Water Resources Research (38) 7-1-7-18
Considerable progress has been made in developing a theoretical framework for modeling slug test responses in formations with high hydraulic conductivity K. However, several questions of practical significance remain unresolved. Given the rapid and often oscillatory nature of test responses, the traditional hydrostatic relationship between the water level and the transducer‐measured...
Status and trends in atmospheric deposition and emissions near Atlanta, Georgia, 1986-99
N.E. Peters, T.P. Meyers, Brent T. Aulenbach
2002, Atmospheric Environment (36) 1577-1588
Wet and dry atmospheric deposition were investigated from weekly data, 1986-99 (1986-97 for dry deposition) at the Panola Mountain Research Watershed (PMRW), a forested research site 25 km, southeast of Atlanta, Georgia. Furthermore, the wet deposition was compared to that at three adjacent National Atmospheric Deposition Program's National Trends Network...
Stress triggering of the 1999 Hector Mine earthquake by transient deformation following the 1992 Landers earthquake
F. F. Pollitz, I. S. Sacks
2002, Bulletin of the Seismological Society of America (92) 1487-1496
The M 7.3 June 28, 1992 Landers and M 7.1 October 16, 1999 Hector Mine earthquakes, California, both right lateral strike-slip events on NNW-trending subvertical faults, occurred in close proximity in space and time in a region where recurrence times for surface-rupturing earthquakes are thousands of years. This suggests a...
Simulation of broadband ground motion including nonlinear soil effects for a magnitude 6.5 earthquake on the Seattle fault, Seattle, Washington
S. Hartzell, A. Leeds, A. Frankel, R. A. Williams, J. Odum, W. Stephenson, W. Silva
2002, Bulletin of the Seismological Society of America (92) 831-853
The Seattle fault poses a significant seismic hazard to the city of Seattle, Washington. A hybrid, low-frequency, high-frequency method is used to calculate broadband (0-20 Hz) ground-motion time histories for a M 6.5 earthquake on the Seattle fault. Low frequencies (1 Hz) are calculated by a stochastic method that uses...
The hydrothermolysis of the picrate anion: Kinetics and mechanism
D.S. Ross, I. Jayaweera
2002, Thermochimica Acta (384) 155-162
The hydrothermolysis of the picrate anion in aqueous solution has been studied at 260-325??C in liquid water. At starting pH values above 12, the disappearance of picrate begins immediately and is first order in OH-. At lower pH, there is an induction period preceding the disappearance, and over the pH...
Relationship of the 1999 Hector Mine and 1992 Landers fault ruptures to offsets on neogene faults and distribution of late Cenozoic basins in the eastern California shear zone
R.C. Jachens, V.E. Langenheim, J. C. Matti
2002, Bulletin of the Seismological Society of America (92) 1592-1605
This report examines the Hector Mine and Landers earthquakes in the broader context of faults and fault-related basins of the eastern California shear zone (ECSZ). We compile new estimates of total strike-slip offset (horizontal separation) at nearly 30 fault sites based on offset magnetic anomaly pairs. We also present a...
Identification of lithofacies using Kohonen self-organizing maps
H.-C. Chang, D. C. Kopaska-Merkel, H.-C. Chen
2002, Computers & Geosciences (28) 223-229
Lithofacies identification is a primary task in reservoir characterization. Traditional techniques of lithofacies identification from core data are costly, and it is difficult to extrapolate to non-cored wells. We present a low-cost automated technique using Kohonen self-organizing maps (SOMs) to identify systematically and objectively lithofacies from well log data. SOMs...
Historical and projected carbon balance of mature black spruce ecosystems across north america: The role of carbon-nitrogen interactions
Joy S. Clein, A. D. McGuire, X. Zhang, D. W. Kicklighter, J. M. Melillo, S.C. Wofsy, P.G. Jarvis, J.M. Massheder
2002, Conference Paper, Plant and Soil
The role of carbon (C) and nitrogen (N) interactions on sequestration of atmospheric CO2 in black spruce ecosystems across North America was evaluated with the Terrestrial Ecosystem Model (TEM) by applying parameterizations of the model in which C-N dynamics were either coupled or uncoupled. First, the performance of the parameterizations,...
Source properties of earthquakes near the Salton Sea triggered by the 16 October 1999 M 7.1 Hector Mine, California, earthquake
S. E. Hough, H. Kanamori
2002, Bulletin of the Seismological Society of America (92) 1281-1289
We analyze the source properties of a sequence of triggered earthquakes that occurred near the Salton Sea in southern California in the immediate aftermath of the M 7.1 Hector Mine earthquake of 16 October 1999. The sequence produced a number of early events that were not initially located by the...
Strong interseismic coupling, fault afterslip, and viscoelastic flow before and after the Oct. 9, 1995 Colima-Jalisco earthquake: continuous GPS measurements from Colima, Mexico
B.M. Azua, C. DeMets, Timothy Masterlark
2002, Geophysical Research Letters (29)
Continuous GPS measurements from Colima, Mexico during 4/93-6/01, bracketing the Oct. 9, 1995 M = 8.0 Colima-Jalisco earthquake, provide new constraints on Rivera plate subduction mechanics. Modeling of margin-normal strain accumulation before the earthquake suggests the Rivera-North America subduction interface was fully locked. Transient postseismic motion from 10/ 95-6/97 is...
Moment-tensor solutions estimated using optimal filter theory: Global seismicity, 2000
S.A. Sipkin, C. G. Bufe, M.D. Zirbes
2002, Physics of the Earth and Planetary Interiors (130) 129-142
Moment-tensor solutions, estimated using optimal filter theory, are listed for 324 moderate-to-large size earthquakes that occurred during the year 2000. Published by Elsevier Science B.V....
Preliminary comparison of landscape pattern-normalized difference vegetation index (NDVI) relationships to central plains stream conditions
J. A. Griffith, E. A. Martinko, J. L. Whistler, K. P. Price
2002, Journal of Environmental Quality (31) 846-859
We explored relationships of water quality parameters with landscape pattern metrics (LPMs), land use–land cover (LULC) proportions, and the advanced very high resolution radiometer (AVHRR) normalized difference vegetation index (NDVI) or NDVI-derived metrics. Stream sites (271) in Nebraska, Kansas, and Missouri were sampled for water quality parameters, the index of...
Regional estimates of radiated seismic energy
J. Boatwright, G. L. Choy, L. C. Seekins
2002, Bulletin of the Seismological Society of America (92) 1241-1255
We revise the spectral technique for estimating radiated energy from recordings of large earthquakes at regional distances (Δ < 200 km) by correcting for geometric spreading and for site amplification as explicit functions of frequency. We analyze 65 recordings of the 1999 Hector Mine earthquake as functions of frequency, distance,...
A statistical evaluation of non-ergodic variogram estimators
F.C. Curriero, M.E. Hohn, A.M. Liebhold, S.R. Lele
2002, Environmental and Ecological Statistics (9) 89-110
Geostatistics is a set of statistical techniques that is increasingly used to characterize spatial dependence in spatially referenced ecological data. A common feature of geostatistics is predicting values at unsampled locations from nearby samples using the kriging algorithm. Modeling spatial dependence in sampled data is necessary before kriging and is...
Tectonics and distribution of gold deposits in China - An overview
T. Zhou, Richard J. Goldfarb, Neil G. Phillips
2002, Mineralium Deposita (37) 249-282
Gold exploration in China has expanded rapidly during the last two decades since a modern approach to economic development has become a national priority. China currently produces 180 tonnes (t) of gold annually, which is still significantly less than South Africa, USA, and Australia. However, China is now recognized as possessing...
Long-term climate patterns in Alaskan surface temperature and precipitation and their biological consequences
James J. Simpson, Gary L. Hufford, Michael D. Fleming, Jared S. Berg, J.B. Ashton
2002, IEEE Transactions on Geoscience and Remote Sensing (40) 1164-1184
Mean monthly climate maps of Alaskan surface temperature and precipitation produced by the parameter-elevation regression on independent slopes model (PRISM) were analyzed. Alaska is divided into interior and coastal zones with consistent but different climatic variability separated by a transition region; it has maximum interannual variability but low long-term mean...
Source of solutes to the coastal sabkha of Abu Dhabi
W.W. Wood, W. E. Sanford, A.R.S. Al Habshi
2002, Geological Society of America Bulletin (114) 259-268
An ascending-brine model is proposed to address the observed isotope geochemistry, solute composition, and solute and water fluxes in the coastal sabkha of the Emirate of Abu Dhabi. Mass-balance measurements document that >95% of the solutes are derived from ascending continental brines; minor amounts are derived from rainfall and from...
Asymptotic approximations to posterior distributions via conditional moment equations
J.L. Yee, W.O. Johnson, F.J. Samaniego
2002, Biometrika (89) 755-767
We consider asymptotic approximations to joint posterior distributions in situations where the full conditional distributions referred to in Gibbs sampling are asymptotically normal. Our development focuses on problems where data augmentation facilitates simpler calculations, but results hold more generally. Asymptotic mean vectors are obtained as simultaneous solutions to fixed point...
Optimal exploitation of spatially distributed trophic resources and population stability
A. Basset, M. Fedele, D.L. DeAngelis
2002, Ecological Modelling (151) 245-260
The relationships between optimal foraging of individuals and population stability are addressed by testing, with a spatially explicit model, the effect of patch departure behaviour on individual energetics and population stability. A factorial experimental design was used to analyse the relevance of the behavioural factor in relation to three factors...
