J. Wynn
2002, Leading Edge (Tulsa, OK) (21) 62-64
No abstract available....
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Publication Extents
Not all publications have extents, not all extents are completely accurateK.J. Ellefsen, D.L. Wright
2002, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
To understand better how a borehole antenna radiates radar waves into a formation, this phenomenon is simulated numerically using the finite-difference, time-domain method. The simulations are of two different antenna models that include features like a driving point fed by a coaxial cable, resistive loading of the antenna, and a...
M. A. Lanphere, D.E. Champion, R.L. Christiansen, G. A. Izett, J. D. Obradovich
2002, Geological Society of America Bulletin (114) 559-568
40Ar/39Ar ages were determined on the three major ash-flow tuffs of the Yellowstone Plateau volcanic field in the region of Yellowstone National Park in order to improve the precision of previously determined ages. Total-fusion and incremental- heating ages of sanidine yielded the following mean ages: Huckleberry Ridge Tuff—2.059 ± 0.004...
A.H. Reed, K.B. Briggs, D. L. Lavoie
2002, IEEE Journal of Oceanic Engineering (27) 581-592
During the 1999 sediment acoustics experiment (SAX99), porometric properties were measured and predicted for a well sorted, medium sand using standard laboratory geotechnical methods and image analysis of resin-impregnated sediments. Sediment porosity measured by laboratory water-weight-loss methods (0.372 ?? 0.0073 for mean ??1 standard deviation) is 0.026 lower than determined...
S.A. Adlerstein, A. Temming, N. Mergardt
2002, ICES Journal of Marine Science (59) 497-515
This study analyses data from over 20 000 haddock stomachs collected during the 1981 and 1991 Stomach Sampling Projects of the North Sea. Sampling was within the framework of the Multispecies Virtual Population Analysis (MSVPA) for fisheries stock assessment. In 1981 stomachs were collected to calculate input feeding parameters from...
Qinfeng Guo, James H. Brown, T. J. Valone
2002, Journal of Vegetation Science (13) 575-584
Winter and summer annuals in the Chihuahuan Desert have been intensively studied in recent years but little is known about the similarities and differences in the dynamics between these two communities. Using 15 yr of census data from permanent quadrats, this paper compared the characteristics and temporal dynamics of these...
M.C. Reheis, S. Stine, A.M. Sarna-Wojcicki
2002, Geological Society of America Bulletin (114) 991-1006
Mono Basin, on the eastern flank of the central Sierra Nevada, is the highest of the large hydrographically closed basins in the Basin and Range province. We use geomorphic features, shoreline deposits, and basalt-filled paleochannels to reconstruct an early to middle Pleistocene record of shorelines and changing spillways of Lake...
J.H. Williams, Frederick L. Paillet
2002, Journal of Hydrology (265) 100-117
Cross-borehole flowmeter pulse tests define subsurface connections between discrete fractures using short stress periods to monitor the propagation of the pulse through the flow system. This technique is an improvement over other cross-borehole techniques because measurements can be made in open boreholes without packers or previous identification of water-producing intervals....
J. N. Aleinikoff, R. P. Wintsch, C.M. Fanning, M. J. Dorais
2002, Chemical Geology (188) 125-147
U-Pb ages for zircon and titanite from a granodioritic gneiss in the Glastonbury Complex, Connecticut, have been determined using both isotope dilution thermal ionization mass spectrometry (TIMS) and the sensitive high resolution ion microprobe (SHRIMP). Zircons occur in three morphologic populations: (1) equant to stubby, multifaceted, colorless, (2) prismatic, dark...
M.V. Matthews, W.L. Ellsworth, P.A. Reasenberg
2002, Bulletin of the Seismological Society of America (92) 2233-2250
We construct a probability model for rupture times on a recurrent earthquake source. Adding Brownian perturbations to steady tectonic loading produces a stochastic load-state process. Rupture is assumed to occur when this process reaches a critical-failure threshold. An earthquake relaxes the load state to a characteristic ground level and begins...
K.F. Stepenuck, R.L. Crunkilton, L. Wang
2002, Conference Paper, Journal of the American Water Resources Association
Macroinvertebrates were used to assess the impact of urbanization on stream quality across a gradient of watershed imperviousness in 43 southeastern Wisconsin streams. The percentage of watershed connected imperviousness was chosen as the urbanization indicator to examine impact of urban land uses on macroinvertebrate communities. Most urban land uses were...
P.S. Chavez Jr., J. Isbrecht, P. Galanis, G.L. Gabel, S.C. Sides, D.L. Soltesz, Stephanie L. Ross, M.G. Velasco
2002, Marine Geology (181) 305-315
Sidescan-sonar imaging systems with digital capabilities have now been available for approximately 20 years. In this paper we present several of the various digital image processing techniques developed by the U.S. Geological Survey (USGS) and used to apply intensity/radiometric and geometric corrections, as well as enhance and digitally mosaic, sidescan-sonar...
J.K. Bohlke
2002, Hydrogeology Journal (10) 438-439
No abstract available....
T. A. Kalvelage
Barnes W.L., editor(s)
2002, Conference Paper
NASA developed the Earth Observing System (EOS) during the 1990'S. At the Land Processes Distributed Active Archive Center (LP DAAC), located at the USGS EROS Data Center, the EOS Data and Information System (EOSDIS) is required to support heritage missions as well as Landsat 7, Terra, and Aqua. The original...
David J. Holtschlag, John A. Koschik
2002, Journal of Great Lakes Research (28) 379-395
St. Clair and Detroit rivers, which are connecting channels between Lake Huron and Lake Erie in the Great Lakes basin, form part of the boundary between the state of Michigan and the province of Ontario. In 13 reaches, this flow divides locally around islands and dikes to form 31 branches....
D. H. Schoellhamer
2002, Estuaries (25) 488-495
Suspended sediment concentration (SSC) data from San Pablo Bay, California, were analyzed to compare the basin-scale effect of dredging and disposal of dredged material (dredging operations) and natural estuarine processes. The analysis used twelve 3-wk to 5-wk periods of mid-depth and near-bottom SSC data collected at Point San Pablo every...
J. T. Randerson, F. S. Chapin III, J.W. Harden, J. C. Neff, M. E. Harmon
2002, Ecological Applications (12) 937-947
The conceptual framework used by ecologists and biogeochemists must allow for accurate and clearly defined comparisons of carbon fluxes made with disparate techniques across a spectrum of temporal and spatial scales. Consistent with usage over the past four decades, we define "net ecosystem production" (NEP) as the net carbon accumulation...
I. Ferrer, E. T. Furlong
2002, Analytical Chemistry (74) 1275-1280
Benzalkonium chlorides (BACs) were successfully extracted from sediment samples using a new methodology based on accelerated solvent extraction (ASE) followed by an on-line cleanup step. The BACs were detected by liquid chromatography/ion trap mass spectrometry (LC/MS) or tandem mass spectrometry (MS/MS) using an electrospray interface operated in the positive ion...
M. McGann
2002, Marine Geology (181) 115-156
Historical (early 1930s) and modern samples provide a detailed account of the spatial distribution of benthic foraminifers on the continental shelf of Monterey Bay, California. Ten species among a total of 110 present dominated the 110 samples investigated in the historical study. A cluster analysis of the foraminiferal abundances in...
S.H. Luijten, M. Kery, J.G.B. Oostermeijer, Nijs H.J.C.M. Den
2002, Journal of Ecology (90) 593-603
1. The genetic constitution of populations may significantly affect demography. Founder populations or isolated remnants may show inbreeding depression, while established populations can be strongly adapted to the local environment. Gene exchange between populations can lead to better performance if heterozygosity levels are restored (heterosis), or to reduced performance if...
Robert E. Bennetts, Wiley M. Kitchens, Victoria Dreitz
2002, Wetlands (22) 366-373
Hydrology frequently has been reported as the environmental variable having the greatest influence on Florida snail kite (Rostrhamus sociabilis) populations. Although drought has received the most attention, high-water conditions also have been reported to affect kites. Years of high water generally have been reported to be favorable for nesting, although...
D. D. Eberl, D. E. Kile, V. A. Drits
2002, American Mineralogist (87) 1235-1241
Geological interpretations of crystal size distributions (CSDs) depend on understanding the crystal growth laws that generated the distributions. Most descriptions of crystal growth, including a population-balance modeling equation that is widely used in petrology, assume that crystal growth rates at any particular time are identical for all crystals, and, therefore,...
R.C. Lewis, K.H. Coale, B. D. Edwards, M. Marot, J.N. Douglas, E.J. Burton
2002, Marine Geology (181) 157-169
The distribution of excess 210Pb in 31 sediment cores was used to determine modern (last 100 yr) mass accumulation rates and the depth of sediment mixing on the continental shelf between Pacifica and Monterey, California, USA. Apparent mass accumulation rates average 0.27 g cm-2 yr-1 and range from 0.42 g...
B. D. Edwards
2002, Marine Geology (181) 83-100
The storm-protected continental shelf of Monterey Bay, part of the Monterey Bay National Marine Sanctuary, north-central California, is subject to abundant, episodic sediment input from fluvial sources. North of Monterey Bay, conditions of reduced sediment supply combined with the exposed nature of the shelf provide an effective laboratory for studying...
J. P. Xu, M. Noble, S.L. Eittreim
2002, Marine Geology (181) 171-193
Suspended sediment transport on the shelves off Santa Cruz and Davenport, California is studied using field measurements and bottom boundary layer modeling. Strong transport events mostly occur during storms in winter; the volume of winter sediment transport is at least one order of magnitude greater than that of summer/spring transport....