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Page 4693, results 117301 - 117325

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Not all publications have extents, not all extents are completely accurate
Air encapsulation during infiltration
Jim Constantz, W.N. Herkelrath, F. Murphy
1988, Soil Science Society of America Journal (52) 10-16
A series of field and laboratory experiments were performed to measure the effects of air encapsulation within the soil's transmission zone upon several infiltration properties. In the field, infiltration rates were measured using a double-cap infiltrometer (DCI), and soil-water contents were measured using time-domain reflectometry (TDR). Before half of the...
Thermal regime of the State 2-14 well, Salton Sea Scientific Drilling Project
J.H. Sass, S. S. Priest, L.E. Duda, C.C. Carson, J. D. Hendricks, L.C. Robison
1988, Journal of Geophysical Research Solid Earth (93) 12995-13004
Temperature logs were made repeatedly during breaks in drilling and both during and after flow tests in the Salton Sea Scientific Drilling Project well (State 2–14). The purpose of these logs was to assist in identifying zones of fluid loss or grain and to characterize reservoir temperatures. At the conclusion...
Environmental impacts and regulatory policy. Implications of spray disposal of dredged material in Louisiana wetlands
Donald R. Cahoon, J.H. Cowan Jr.
1988, Coastal Management (16) 341-362
The capabilities of a new wetland dredging technology were assessed along with associated newly developed state and federal regulatory policies to determine if policy expectations realistically match the technological achievement. Current regulatory practices require amelioration of spoil bank impacts upon abandonment of an oil/gas well, but this may not occur...
Semianalytical computation of path lines for finite-difference models
D.W. Pollock
1988, Ground Water (26) 743-750
A semianalytical particle tracking method was developed for use with velocities generated from block centered finite-difference ground-water flow models. The method is based on the assumption that each directional velocity component varies linearly within a grid cell in its own coordinate directions. This assumption allows...
Fractional-step method for two-dimensional estuarine transport
Jerad D. Bales, Edward R. Holley
1988, Conference Paper
The fractional-step method was used in this study to split the longitudinal advective transport term from the other terms in the two-dimensional, laterally-averaged equation for estuarine mass transport. The method of characteristics with spline interpolations was used to approximate the longitudinal advective transport. A general discussion of the fractional-step method,...
Molecular composition and mobility of torbanite precursors: Implications for the structure of coal
M. A. Wilson, B.D. Batts, Patrick G. Hatcher
1988, Energy & Fuels (2) 668-672
Coorongite, a torbanite precursor found in South Australia, and algal residues derived from Botryococcus braunii and other algae have been examined by solid-state 13C NMR techniques. The majority of carbon in these materials is present as (CH2)n. However, variable-temperature studies show that a considerable proportion of the alkyl chains have...
Mechanistic characterization of chloride interferences in electrothermal atomization systems
J.M. Shekiro Jr., R.K. Skogerboe, Howard E. Taylor
1988, Analytical Chemistry (60) 2578-2582
A computer-controlled spectrometer with a photodiode array detector has been used for wavelength and temperature resolved characterization of the vapor produced by an electrothermal atomizer. The system has been used to study the chloride matrix interference on the atomic absorption spectrometric determination of manganese and copper. The suppression of manganese...
Geohydrologic aspects of water-quality problems of the San Joaquin Valley, California
S. J. Deverel
1988, Conference Paper
Salinity and selenium concentrations in shallow ground water of the western San Joaquin Valley, California, are related to the geomorphology and hydrology of the alluvial fans. High salinity and selenium concentrations are associated with ephemeral-stream deposits. Low salinity and selenium concentrations are associated with intermittent-stream deposits, which represent the major...
The representativeness of pore water samples collected from the unsaturated zone using pressure-vacuum lysimeters
Charles A. Peters, Richard W. Healy
1988, Ground Water Monitoring Review (8) 96-101
Pressure-vacuum lysimeters are an inexpensive means of collecting numerous water samples from the same location in the unsaturated zone over a period of time. However, prior studies have indicated that the chemistry of water samples may be altered by the collection technique, creating concern about the representativeness of the pore...
Tectonic significance of dikes of Westerly Granite, southeastern Connecticut and southwestern Rhode Island
R. Goldsmith
1988, Northeastern Geology (10) 195-201
Undeformed Early Permian Westerly Granite dikes cut gneisses of the southeastern New England Avalon zone along coastal southeastern Connecticut and adjacent Rhode Island. Most dikes dip southward at a low angle. The Westerly dikes were emplaced in relatively warm rock penecontemporaneously with the Narragansett Pier Granite during a narrow time...
Relationships of phytomacrofauna to surface area in naturally occurring macrophyte stands
Charles L. Brown, Thomas P. Poe, John R. P. French III, Donald W. Schloesser
1988, Journal of the North American Benthological Society (7) 129-139
Most studies of the relationships between freshwater macrophytes and phytomacrofauna, or the macroinvertebrates associated with the macrophytes, have been based on individual plant collections or samples from monotypic plant stands. We describe the phytomacrofauna assemblages within naturally occurring, taxonomically mixed stands, and consider how macrophyte surface area and plant...
Cathodoluminescent bimineralic ooids from the Pleistocene of the Florida continental shelf
R. P. Major, Robert B. Halley, Karen J. Lukas
1988, Sedimentology (35) 843-855
A bored and encrusted late Pleistocene ooid grainstone was recovered from the seafloor at a depth of approximately 40 m on the outer continental shelf of eastern Florida. Ooid cortices are dominantly bimineralic, generally consisting of inner layers of radial magnesian calcite and outer layers of tangential aragonite. Ooid nuclei...
A tentative protocol for measurement of radon availability from the ground
A.B. Tanner
1988, Radiation Protection Dosimetry (24) 79-83
A procedure is being tested in order to determine its suitability for assessing the intrinsic ability of the ground at a particular site to supply 222Rn to a basement structure to be built on the site. Soil gas is sucked from a borehole probe through an alpha scintillation chamber and flow...
Comparison of hatchery-reared lake trout stocked as fall fingerlings and as spring yearlings in Lake Ontario
Joseph H. Elrod, David E. Ostergaard, Clifford P. Schneider
1988, North American Journal of Fisheries Management (8) 455-462
We made 16 paired releases of lake trout Salvelinus namaycush of four year classes (1979–1982) at five locations to compare survival and growth of hatchery-reared fish stocked as fall fingerlings (FF) and as spring yearlings (SY). Comparisons were based on fish at ages 2–8 recovered with bottom trawls, with gill nets, and...
Icebergs rework shelf sediments to 500 m off Antarctica
P. W. Barnes, R. Lien
1988, Geology (16) 1130-1133
Icebergs and sea ice rework the sediments of high-latitude shelves, producing modern diamicts (ice-keel turbates) unrelated to glacial proximity. Off Antarctica, sidescan sonar data indicate the presence of ice-gouge features formed by the physical interaction between ice keels and the sea bed. These...
Magmatic heat and the El Nino cycle
H. R. Shaw, J.G. Moore
1988, Eos, Transactions, American Geophysical Union (69) 1553-1565
Large submarine lava flows with apparent volumes exceeding 10 km3 have recently been imaged on the deep ocean floor in various parts of the Pacific by means of GLORIA and SeaMarc side-looking sonar surveys. Such flows may produce thermal anomalies large enough to perturb the cyclic processes...
Sr and Nd isotopic variations in ferromanganese crusts from the Central Pacific: Implications for age and source provenance
K. Futa, Z. E. Peterman, J.R. Hein
1988, Geochimica et Cosmochimica Acta (52) 2229-2233
Isotopic analyses of two hydrogenetic ferromanganese (Fe-Mn) crusts from volcanic edifices in the central Pacific Ocean reveal systematic variations in 87Sr86Sr">87Sr86Sr and 143Nd144Nd">143Nd144Nd, with both ratios decreasing as a function of depth into the Fe-Mn crusts. Leaching experiments suggest that Sr...
Chemical characterization and mutagenic properties of polycyclic aromatic compounds in sediment from tributaries of the Great Lakes
David L. Fabacher, Christopher J. Schmitt, John M. Besser, Michael J. Mac
1988, Environmental Toxicology and Chemistry (7) 529-543
Sediments from four inshore industrial sites and a reference site in the Great Lakes were extracted with solvents and characterized chemically for polycyclic aromatic compounds (PACs). An aqueous phase and a crude organic extract were obtained. The crude organic extract was further resolved into fractions A-2 (polycyclic aromatic hydrocarbons) and...
Ocean plateau-seamount origin of basaltic rocks, Angayucham terrane, central Alaska
F. Barker, D. L. Jones, J. R. Budahn, P.J. Coney
1988, Journal of Geology (96) 368-374
The Angayucham terrane of north-central Alaska (immediately S of the Brooks Range) is a large (ca. 500 km E-W), allochthonous complex of Devonian to Lower Jurassic pillow basalt, diabase sills, gabbro plutons, and chert. The mafic rocks are transitional normal-to-enriched, mid-ocean-ridge (MORB) type tholeiites (TiO2 1.2-3.4%, Nb 7-23 ppm, Ta...
Petrology and hydrothermal mineralogy of US Geological Survey Newberry: 2. Drill core from Newberry Caldera, Oregon
T. E. C. Keith, K.E. Bargar
1988, Journal of Geophysical Research Solid Earth (93) 10174-10190
U.S. Geological Survey Newberry 2 was drilled to a depth of 932 m within Newberry caldera. The bottom-hole temperature of 265°C is the highest reported temperature of any drill hole in the Cascades region of the United States. The upper part of the stratigraphic section penetrated by Newberry 2 consists...
A statistical evaluation of formation disturbance produced by well- casing installation methods
R. H. Morin, Denis R. LeBlanc, W.E. Teasdale
1988, Ground Water (26) 207-217
Water-resources investigations concerned with contaminant transport through aquifers comprised of very loose, unconsolidated sediments have shown that small-scale variations in aquifer characteristics can significantly affect solute transport and dispersion. Commonly, measurement accuracy and resolution have been limited by a borehole environment consisting of an annulus of disturbed sediments produced by...
Erosional furrows formed during the lateral blast at Mount St. Helens, May 18, 1980
S. W. Kieffer, B. Sturtevant
1988, Journal of Geophysical Research Solid Earth (93) 14793-14816
Nearly horizontal, quasi-periodic erosional features of 7-m average transverse wavelength and of order 100-m length occur in scattered locations from 3.5 to 9 km from the crater at Mount St. Helens under deposits of the lateral blast of May 18, 1980. We attribute the erosional features to scouring by longitudinal...