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Page 5167, results 129151 - 129175

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Probability weighted moments compared with some traditional techniques in estimating Gumbel Parameters and quantiles
J. Maciunas Landwehr, N.C. Matalas, J.R. Wallis
1979, Water Resources Research (15) 1055-1064
Estimates of the parameters and quantiles of the Gumbel distribution by the methods of probability weighted moments, (conventional) moments, and maximum likelihood were compared. Results were derived from Monte Carlo experiments by using both independent and serially correlated Gumbel numbers. The method of probability weighted moments was seen...
An algol program for dissimilarity analysis: a divisive-omnithetic clustering technique
J.C. Tipper
1979, Computers & Geosciences (5) 1-13
Clustering techniques are used properly to generate hypotheses about patterns in data. Of the hierarchical techniques, those which are divisive and omnithetic possess many theoretically optimal properties. One such method, dissimilarity analysis, is implemented here in ALGOL 60, and determined to be competitive computationally with most other methods. ?? 1979....
Low-velocity impact craters in ice and ice-saturated sand with implications for Martian crater count ages
S.K. Croft, S. W. Kieffer, T.J. Ahrens
1979, Journal of Geophysical Research Solid Earth (84) 8023-8032
We produced a series of decimeter-sized impact craters in blocks of ice near 0°C and −70°C and in ice-saturated sand near −70°C as a preliminary investigation of cratering in materials analogous to those found on Mars and the outer solar system satellites. The projectiles used were standard 0.22 and 0.30...
Geochemical and hydrologic considerations and the use of enthalpy-chloride diagrams in the prediction of underground conditions in hot-spring systems
R.O. Fournier
1979, Journal of Volcanology and Geothermal Research (5) 1-16
Thermal water ascending in a hot-spring system may cool by conduction of heat to the surrounding rock, by boiling, by mixing with cooler water, or by a combination of these processes. Complete or partial chemical reequilibration may occur as a result of this cooling. In spite of these complexities, in...
A review of recent activity in the United States.
H.L. Cannon, W.L. Petrie
1979, Philosophical Transactions of the Royal Society B: Biological Sciences (288) 137-149
Either an overabundance or a deficiency of trace metals in the food chain can ultimately affect adversely the health of livestock and man. Increasing interest in the United States in the distribution of metals in the environment and in metal pollutants has led to widespread interdisciplinary research sponsored by governmental,...
The Yellow Dog peridotite and a possible buried igneous complex of lower Keweenawan age in the northern peninsula of Michigan
John S. Klasner, David W. Snider, W.F. Cannon, John F. Slack
1979, Michigan Geological Survey Report of Investigation 24
Partly serpentinized peridotite of early Keweenawan age crops out in two places along a 20-kilometer-long zone of positive aeromagnetic anomalies in northern Marquette County, Michigan. Most of the area is mantled by Pleistocene drift with few bedrock exposures.Petrographic and electron microprobe studies show that the peridotite was originally a plagioclase...
Computers at the Albuquerque Seismological Laboratory
J. Hoffman
1979, Earthquake Information Bulletin (USGS) (11) 138-140
The Worldwide Standardized Seismograph Network (WWSSN) is managed by the U.S Geological Survey in Albuquerque, N. Mex. It consists of a global network of seismographs housed in seismic observatories throughout the world. An important recent addition to this network are the Seismic Research Observatories (SRO) which combine a borehole seismometer...
Tufted Puffins nesting in estuarine habitat
Robert E. Gill Jr., Gerald A. Sanger
1979, The Auk (96) 792-794
The Tufted Puffin (Lunda cirrhata) apparently has the most extensive breeding distribution of any North Pacific seabird, extending in the western North Pacific from Hokkaido to the north Chukotsk Peninsula on the Chukchi Sea, and in North America from Cape Lisburne on the Chukchi Sea, south to the Farallon Islands...
A new instrument system to investigate sediment dynamics on continental shelves
D.A. Cacchione, D.E. Drake
1979, Marine Geology (30) 299-312
A new instrumented tripod, the GEOPROBE system, has been constructed and used to collect time-series data on physical and geological parameters that are important in bottom sediment dynamics on continental shelves. Simultaneous in situ digital recording of pressure, temperature, light scattering, and light transmission, in combination with current velocity profiles...
Amino acid racemization dating of fossil bones, I. inter-laboratory comparison of racemization measurements
J.L. Bada, E. Hoopes, D. Darling, G. Dungworth, H.J. Kessels, K.A. Kvenvolden, D.J. Blunt
1979, Earth and Planetary Science Letters (43) 265-268
Enantiomeric measurements for aspartic acid, glutamic acid, and alanine in twenty-one different fossil bone samples have been carried out by three different laboratories using different analytical methods. These inter-laboratory comparisons demonstrate that D/L aspartic acid measurements are highly reproducible, whereas the enantiomeric measurements...
Beach-cusp formation
A. H. Sallenger Jr.
1979, Marine Geology (29) 23-37
Field experiments on beach-cusp formation were undertaken to document how the cuspate form develops and to test the edge-wave hypothesis on the uniform spacing of cusps. These involved observations of cusps forming from an initially plane foreshore. The cuspate form was observed to be a product of swash modification of an...
Origin of reverse-graded bedding in air-fall pumice, Coso Range, California
W. A. Duffield, C. R. Bacon, G.R. Roquemore
1979, Journal of Volcanology and Geothermal Research (5) 35-48
The origin of reverse grading in air-fall pyroclastic deposits has been ascribed to: (1) changing conditions at an erupting vent; (2) deposition in water; or (3) rolling of large clasts over smaller clasts on the surface of a steep slope. Structural features in a deposit of air-fall pumice lapilli in...
Disequilibrium in the 238uranium series in samples from Yeelirrie, Western Australia
R.S. Lively, R.S. Harmon, A. A. Levinson, C.J. Bland
1979, Journal of Geochemical Exploration (12) 57-65
Uranium-series disequilibrium studies carried out on samples from the Yeelirrie uranium deposit, Western Australia, indicate that uranium and radium have been migrating within the deposit during recent times, and are actually being removed from the deposit. Samples collected for 230Th/234U age dating were found to be substantially out of equilibrium,...
Submarine thermal springs on the Galapagos Rift
J.B. Corliss, J. Dymond, L.I. Gordon, J.M. Edmond, R. P. Von Herzen, Richard D. Ballard, K. Green, D. Williams, A. Bainbridge, K. Crane, T. H. Van Andel
1979, Science (203) 1073-1083
The submarine hydrothermal activity on and near the Galápagos Rift has been explored with the aid of the deep submersible Alvin. Analyses of water samples from hydrothermal vents reveal that hydrothermal activity provides significant or dominant sources and sinks for several components of seawater; studies of conductive and convective heat transfer...
Arsenic and fluoride in the upper madison river system: Firehole and gibbon rivers and their tributaries, yellowstone national park, wyoming, and southeast montana
J. M. Thompson
1979, Environmental Geology (3) 13-21
Chemical analyses of 21 water samples from the Firehole and Gibbon Rivers, which combine to form the Madison River, gave arsenic and fluoride values above the Environmental Protection Agency Interim Primary Drinking Water maximum contaminant levels (0.05 mg/l arsenic and 2.0 mg/l fluoride). On 18 October, 1975, during a period...
A review of numerical simulation of hydrothermal systems
J.W. Mercer, C.R. Faust
1979, Hydrological Sciences Bulletin (24) 335-344
Many advances in simulating single and two-phase fluid flow and heat transport in porous media have recently been made in conjunction with geothermal energy research. These numerical models reproduce system thermal and pressure behaviour and can be used for heat-transport problems other than those associated with geothermal energy development, such...
Atomic-absorption spectrometric determination of cobalt, nickel, and copper in geological materials with matrix masking and chelation-extraction
R. F. Sanzolone, T. T. Chao, G. L. Crenshaw
1979, Analytica Chimica Acta (105) 247-253
An atomic-absorption spectrometric method is reported for the determination of cobalt, nickel, and copper in a variety of geological materials including iron- and manganese-rich, and calcareous samples. The sample is decomposed with HP-HNO3 and the residue is dissolved in hydrochloric acid. Ammonium fluoride is added to mask iron and 'aluminum. After...
D/H ratios in speleothem fluid inclusions: A guide to variations in the isotopic composition of meteoric precipitation?
R.S. Harmon, H.P. Schwarcz, J. R. O’Neil
1979, Earth and Planetary Science Letters (42) 254-266
D/H ratios of fluid inclusion waters extracted from230Th/234U-dated speleothems that were originally deposited under conditions of isotopic equilibrium should provide a direct estimate of the hydrogen isotopic composition of ancient meteoric waters. We present here D/H ratios for 47 fluid inclusion...
U-Th-Pb geochronology of the Massabesic Gneiss and the granite near Milford, South-Central New Hampshire: New evidence for avalonian basement and taconic and alleghenian disturbances in Eastern New England
J. N. Aleinikoff, R. E. Zartman, J.B. Lyons
1979, Contributions to Mineralogy and Petrology (71) 1-11
U-Th-Pb systematics for zircon and monazite from Massabesic Gneiss (paragneiss and orthogneiss) and the granite near Milford, New Hampshire, were determined. Zircon morphology suggests that the paragneiss may be volcaniclastic (igneous) in origin, and thus the age data probably record the date (minimum of 646 m.y.) at which the rock...
Uranium transport in the Walker River Basin, California and Nevada
L. V. Benson, D. L. Leach
1979, Journal of Geochemical Exploration (11) 227-248
During the summer of 1976 waters from tributaries, rivers, springs and wells were sampled in the Walker River Basin. Snow and sediments from selected sites were also sampled. All samples were analyzed for uranium and other elements. The resulting data provide an understanding of the transport of uranium within...
Recent developments in uranium exploration using the U.S. Geological Survey's mobile helium detector
G.M. Reimer, E.H. Denton, I. Friedman, J. K. Otton
1979, Journal of Geochemical Exploration (11) 1-12
A mobile mass spectrometer to measure He concentrations has been developed by the U.S. Geological Survey. This instrument has been tested in areas of known uranium deposits, and He anomalies have been found in both soil gas and water. A gas sample is collected in a hypodermic syringe, injected into...