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Page 4688, results 117176 - 117200

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Distribution and mobility of selenium and other trace elements in shallow groundwater of the western San Joaquin Valley, California
S. J. Deverel, S.P. Milliard
1988, Environmental Science & Technology (22) 697-702
Samples of shallow groundwater that underlies much of the irrigated area in the western San Joaquin Valley, CA, were analyzed for various major ions and trace elements, including selenium. Concentrations of the major ions generally were similar for groundwater collected in the two primary geologic zones - the alluvial fan...
Upper mantle electrical conductivity for seven subcontinental regions of the Earth
W.H. Campbell, E.R. Schiffmacher
1988, Journal of Geomagnetism & Geoelectricity (40) 1387-1406
Spherical harmonic analysis coefficients of the external and internal parts of the quiet-day geomagnetic field variations (Sq) separated for the seven continental regions of the observatories have been used to determine conductivity profiles to depths of about 600km by the Schmucker equivalent substitute conductor method. The profiles give...
Chemistry and geothermometry of brine produced from the Salton Sea Scientific drill hole, Imperial Valley, California
J. M. Thompson, R.O. Fournier
1988, Journal of Geophysical Research Solid Earth (93) 13165-13173
The December 29–30, 1985, flow test of the State 2–14 well, also known as the Salton Sea Scientific drill hole, produced fluid from a depth of 1865–1877 m at a reservoir temperature of 305° ± 5°C. Another flow test at a depth of 3170 m produced brine contaminated by drilling...
General two‐point method for Determining velocity in open channel
John F. Walker
1988, Journal of Hydraulic Engineering (114) 801-805
The generally accepted procedure is to average velocity measurements at 0. 2D and 0. 8D, measured vertically from the water surface,or alternatively to measure velocity at a position equal to 0. 6D, where D is the total depth of flow. In some situations, one may wish to measure at depths...
Downslope Eulerian mean flow associated with high-frequency current fluctuations observed on the outer continental shelf and upper slope along the northeastern United States continental margin: Implications for sediment transport
B. Butman
1988, Continental Shelf Research (8) 811-840
Eulerian current measurements made 5-7 m above bottom at six stations along the United States east coast continental margin show a net downslope flow of 1-5 cm s-1. Although the scalar current speed decreases with water depth and toward the bottom, fluctuations in the cross-isobath flow were stronger and increasingly...
Stratigraphy and magnetic polarity of the high terrace remnants in the upper Ohio and Monongahela Rivers in West Virginia, Pennsylvania, and Ohio
R. B. Jacobson, D. P. Elston, John W. Heaton
1988, Quaternary Research (29) 216-232
A synthesis of previous work and new data on the stratigraphy of high terraces of the Ohio and Monongahela Rivers upstream from Parkersburg, West Virginia, indicates a correspondence between terrace histories in the ancient Teays and Pittsburgh drainage basins. Four terraces are identified in each. Sediments of the lower three...
Physical deposit measures and commercial potential: The case of titanium-bearing heavy-mineral deposits
E. D. Attanasi, J.H. DeYoung Jr.
1988, Mathematical Geology (20) 97-110
Physical measures of mineral deposit characteristics, such as grade and tonnage, long have been used in both subjective and analytic models to predict favorability of areas for the occurrence of mineral deposits of particular types. After a deposit has been identified, however, the explorationist must decide whether to continue data...
Coarse-sediment bands on the inner shelf of southern Monterey Bay, California
R. E. Hunter, J.R. Dingler, R. J. Anima, B. M. Richmond
1988, Marine Geology (80) 81-98
Bands of coarse sand that trend parallel to the shore, unlike the approximately shore-normal bands found in many inner shelf areas, occur in southern Monterey Bay at water depths of 10–20 m, less than 1 km from the shore. The bands are 20–100 m wide and alternate with bands...
Effects of Precipitation and Land Use on Storm Runoff
R. G. Brown
1988, Water Resources Bulletin (24) 421-426
Storm-runoff quantity and quality were studied in three watersheds located near St. Paul in Ramsey County, Minnesota, from April 15 through September 15 of 1984, 1985, and 1986 to qualitatively determine the effects of precipitation and selected land uses on storm runoff. In respect to precipitation effects, differences in storm-runoff...
Determining baseline element composition of lichens. I. Parmelia sulcata at Theodore Roosevelt National Park, North Dakota
L. P. Gough, R. C. Severson, L. L. Jackson
1988, Water, Air, & Soil Pollution (38) 157-167
Element-concentration baselines are given for Parmelia sulcata and associated soils. Parmelia chlorochroa was found sporadically and therefore only representative concentration ranges are reported for this species. Element data include (1) for lichens; Al, As, Ba, B, Ca, Cr, Cu, Fe, Hg, Mn, Ni, P, Sr, S, Ti, V, Y, and Zn; and (2) for...
Eutrophication of lakes and reservoirs: A framework for making management decisions
W. Rast, M. Holland
1988, Ambio (17) 2-12
The development of management strategies for the protection of environmental quality usually involves consideration both of technical and nontechnical issues. A logical, step-by-step framework for development of such strategies is provided. Its application to the control of cultured eutrophication of lakes and reservoirs illustrates its potential usefulness. From the perspective...
Characterization of humic acid fractions by C-13 nuclear magnetic resonance spectroscopy
Robert L. Wershaw, Kevin A. Thorn, D.J. Pinckney
1988, Environmental Technology Letters (9) 53-62
Soil humic acids from different environments were fractionated by adsorption chromatography on Sephadex and characterized by C‐13 nuclear magnetic resonance (NMR) spectroscopy. The C‐13 NMR spectra of the fractions consist of some sharp, well‐resolved lines and some broad bands in contrast to the spectra of the unfractionated humic acids, where...
Leachate generated by an oil-and-gas brine pond site in North Dakota
E.C. Murphy, A.E. Kehew, G.H. Groenewold, W.A. Beal
1988, Groundwater (26) 31-38
Two unlined ponds were used for holding and evaporation of brines produced with oil and gas at a well site in north-central North Dakota. The brine-evaporation ponds were in use from 1959 up to the late 1970s when they were backfilled and leveled. Continued salt-water...
The northeastern Ohio earthquake of 31 January 1986: Was it induced?
C. Nicholson, E. Roeloffs, R. L. Wesson
1988, Bulletin of the Seismological Society of America (78) 188-217
On 31 January 1986, at 11:46 EST, an earthquake of mb = 5.0 occurred about 40 km east of Cleveland, Ohio, and about 17 km south of the Perry Nuclear Power Plant. The earthquake was felt over a broad area, including 11 states, the District of Columbia, and parts of...
Making maps with computers
S.C. Guptill, L.E. Starr
1988, American Scientist (76) 136-142
Soon after their introduction in the 1950s, digital computers were used for various phases of the mapping process, especially for trigonometric calculations of survey data and for orientation of aerial photographs on map manuscripts. In addition, computer-controlled plotters were used to draw simple outline maps. The process of collecting data...
Taolin Zn-Pb-fluorite deposit, People's Republic of China: An example of some problems in fluid inclusion research on mineral deposits
E. Roedder, K.W. Howard
1988, Journal of the Geological Society (145) 163-174
The large Taolin zinc–lead–fluorite deposit in the People’s Republic of China was discovered 28 years ago, but whether its genetic affiliation is Mississippi Valley-type, epithermal, or mesothermal has remained uncertain. Both the ore and gangue (cherty to coarse quartz, plus barite, chlorite and calcite) occur as open space filling in...
Paleoseismicity and neotectonics of the Cordillera Blanca fault zone, northern Peruvian Andes
David P. Schwartz
1988, Journal of Geophysical Research Solid Earth (93) 4712-4730
The Cordillera Bianca fault zone is a major west dipping normal fault that bounds the west side of a 120- to 170-km-wide zone of active extension along the crest of the northern Peruvian Andes. The fault is approximately 210 km long and exhibits continuous geomorphic evidence of repeated late Pleistocene...
Geometry of the Juan de Fuca plate beneath Washington and northern Oregon from seismicity
C.S. Weaver, G.E. Baker
1988, Bulletin of the Seismological Society of America (78) 264-275
Earthquake hypocenters within the subducting Juan de Fuca plate beneath Washington and northern Oregon are interpreted as showing that the direction of plate dip changes from northeast beneath the Puget Sound region to east-southeast beneath southwestern Washington. The shallowest hypocenters within the Juan de Fuca plate are between 30- to...
The mechanics of ground deformation precursory to dome-building extrusions at Mount St. Helens 1981-1982
W.W. Chadwick Jr., R.J. Archuleta, D. A. Swanson
1988, Journal of Geophysical Research Solid Earth (93) 4351-4366
Detailed monitoring at Mount St. Helens since 1980 has enabled prediction of the intermittent eruptive activity (mostly dome growth) with unprecedented success. During 1981 and 1982, accelerating deformation of the crater floor around the vent (including radial cracks, thrust faults, and ground tilt) was the earliest indicator of impending activity....
A statistical method for estimating rates of soil development and ages of geologic deposits: A design for soil-chronosequence studies
P. Switzer, J.W. Harden, R. K. Mark
1988, Mathematical Geology (20) 49-61
A statistical method for estimating rates of soil development in a given region based on calibration from a series of dated soils is used to estimate ages of soils in the same region that are not dated directly. The method is designed specifically to account for sampling procedures and uncertainties...
Processes affecting the distribution of selenium in shallow groundwater of agricultural areas, western San Joaquin Valley, California
S. J. Deverel, Roger Fujii
1988, Water Resources Research (24) 516-524
A study was undertaken to evaluate the processes affecting the chemistry of shallow groundwater associated with agricultural drainage systems in the western San Joaquin Valley, California. The study was prompted by a need for an understanding of selenium mobility in areas having high selenium concentrations in shallow groundwater. Groundwater samples...
An economic and geographic appraisal of a spatial natural hazard risk: a study of landslide mitigation rules
R. L. Bernknopf, D.S. Brookshire, R. H. Campbell, C.D. Shapiro
1988, Environment and Planning A (20) 621-631
Efficient mitigation of natural hazards requires a spatial representation of the risk, based upon the geographic distribution of physical parameters and man-related development activities. Through such a representation, the spatial probability of landslides based upon physical science concepts is estimated for Cincinnati, Ohio. Mitigation programs designed to reduce loss from...