Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

165626 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 5568, results 139176 - 139200

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Water quality effects of seepage from earthen dams
C. Yost Jr., J.W. Naney
1974, Journal of Hydrology (21) 15-26
Analyses of surface and seepage waters from selected floodwater retarding structures in west-central Oklahoma, U.S.A. show the salinity of seepage to be several times greater than that of the impounded waters. The increases in concentration of the several chemical components are not proportional....
Osmium, ruthenium, iridium and uranium in silicates and chromite from the eastern Bushveld Complex, South Africa
R.h. Gijbels, Hugh T. Millard Jr., G. A. Desborough, A.J. Bartel
1974, Geochimica et Cosmochimica Acta (38) 319-337
Osmium, ruthenium, iridium and uranium contents were determined in eight ortho pyroxene, seven plagioclase, and three chromite mineral separates from the eastern Bushveld Complex. Neutron activation analysis was used to measure the platinum metals, and uranium was determined by a fission track technique....
Episodic Cenozoic volcanism and tectonism in the Andes of Peru
D. C. Noble, E.H. McKee, E. Farrar, U. Petersen
1974, Earth and Planetary Science Letters (21) 213-220
Radiometric and geologic information indicate a complex history of Cenozoic volcanism and tectonism in the central Andes. K-Ar ages on silicic pyroclastic rocks demonstrate major volcanic activity in central and southern Peru, northern Chile, and adjacent areas during the Early and Middle...
Problems encountered in the use of neutron methods for elemental analysis on planetary surfaces
F. Senftle, P. Philbin, R. Moxham, G. Boynton, J. Trombka
1974, Nuclear Instruments and Methods (117) 435-443
From experimental studies of gamma rays from fast and thermal neutron reactions in hydrogeneous and non-hydrogeneous, semi-infinite samples and from Monte Carlo calculations on soil of a composition which might typically be encountered on planetary surfaces, it is found that gamma rays from...
A solvent extraction study of molybdenum chloride and molybdenum thiocyanate complexes
L. P. Greenland, E.G. Lillie
1974, Analytica Chimica Acta (69) 335-346
The effect of reducing agents on molybdenum(VI) solutions in hydrochloric acid was studied by a solvent extraction technique to elucidate the composition of the colored molybdenum thiocyanate complex. Neither copper(I) chloride nor ascorbic acid have any effect on the extraction of MoO2Cl2; it is inferred...
Spectrophotometric determination of molybdenum in rocks with thiocyanate
E.G. Lillie, L. P. Greenland
1974, Analytica Chimica Acta (69) 313-320
A rapid procedure for the determination of microgram amounts of molybdenum in rocks is described. After acid decomposition, molybdenum is extracted from a hydrochloric acid solution into xylene with tributyl phosphate. After back-extraction with water, molybdenum is extracted as the α-benzoinoximate into chloroform, stripped into...
Interlamellar adsorption of carbon dioxide by smectites
J.J. Fripiat, M.I. Cruz, B.F. Bohor, J. Thomas Jr.
1974, Clays and Clay Minerals (22) 23-30
The adsorption of CO2 at low temperature (∼ −70°C) on thin films of homoionic smectites was studied by X-ray diffraction and by i.r. absorption. An increase in the d001 spacings of these clay films upon adsorption of CO2 was observed. In addition, a dichroic effect was readily discernible by comparing the i.r. spectra at...
Craters on Earth, Moon, and Mars: Multivariate classification and mode of origin
R.J. Pike
1974, Earth and Planetary Science Letters (22) 245-255
Testing extraterrestrial craters and candidate terrestrial analogs for morphologic similitude is treated as a problem in numerical taxonomy. According to a principal-components solution and a cluster analysis, 402 representative craters on the Earth, the Moon, and Mars divide into two major classes...
Movement of elements into the atmosphere from coniferous trees in subalpine forests of Colorado and Idaho
G.C. Curtin, H. D. King, E. L. Mosier
1974, Journal of Geochemical Exploration (3) 245-263
Exudates from conifer trees, presumably consisting largely of volatile materials, were sampled at 19 subalpine localitites in Colorado and Idaho where anomalous amounts of several metals were determined in vegetation and mull during previous geochemical testing. The trees sampled were lodgepole pine...
Naturally occurring vapor-liquid-solid (VLS) Whisker growth of germanium sulfide
R. B. Finkelman, R.R. Larson, E.J. Dwornik
1974, Journal of Crystal Growth (22) 159-160
The first naturally occurring terrestrial example of vapor-liquid-solid (VLS) growth has been observed in condensates from gases released by burning coal in culm banks. Scanning electron microscopy, X-ray diffraction, and energy dispersive analysis indicate that the crystals consist of elongated rods (≈ 100...
Martian planetwide crater distributions: Implications for geologic history and surface processes
L.A. Soderblom, C.D. Condit, R.A. West, B.M. Herman, T. J. Kreidler
1974, Icarus (22) 239-263
Population-density maps of craters in three size ranges (0.6 to 1.2 km, 4 to 10 km, and >20 km in diameter) were compiled for most of Mars from Mariner 9 imagery. These data provide: historical records of the eolian processes (0.6 to 1.2 km craters); stratigraphic, relative, and absolute timescales...
Argillization by descending acid at Steamboat Springs, Nevada
Robert Schoen, Donald E. White, J.J. Hemley
1974, Clays and Clay Minerals (22) 1-22
Steamboat Springs, Nevada, an area of present-day hot springs, clearly illustrates the genetic dependence of some kaolin deposits on hot-spring activity. Andesite, granodiorite and arkosic sediments are locally altered at the land surface to siliceous residues consisting of primary quartz and anatase, plus opal from primary silicates. These siliceous residues...
A probe for sampling interstitial waters of stream sediments and bog soils
G.A. Nowlan, C. Carollo
1974, Journal of Geochemical Exploration (3) 199-205
A probe for sampling interstitial waters of stream sediments and bog soils is described. Samples can be obtained within a stratigraphic interval of 2–3 cm, to a depth of 60–80 cm, and with little or no contamination of the samples by sediment or...
40Ar/39Ar age spectra of some undisturbed terrestrial samples
G. Brent Dalrymple, M. A. Lanphere
1974, Geochimica et Cosmochimica Acta (38) 715-738
40Ar/39Ar age spectra and 40Ar/36Ar vs 39Ar/36Ar isochrons were determined by incremental heating for 11 terrestrial rocks and minerals whose geology indicates that they represent essentially undisturbed systems. The samples include muscovite, biotite, hornblende, sanidine, plagioclase, dacite, diabase and basalt and range in age from...
Reference samples for the earth sciences
F.J. Flanagan
1974, Geochimica et Cosmochimica Acta (38) 1731-1744
A revised list of reference samples of interest to geoscientists has been extended to include samples for the agronomist, the archaeologist and the environmentalist. In addition to the source from which standard samples may be obtained, references or pertinent notes for some samples are included.The number of rock reference samples...
Heat flow from eastern Panama and northwestern Colombia
J.H. Sass, R. J. Munroe, T. H. Moses Jr.
1974, Earth and Planetary Science Letters (21) 134-142
Heat flows were determined at 12 sites in four distinct areas between longitude 77° and 80°W in eastern Panama and northwestern Colombia. Evidently, most of the region is underlain by mafic oceanic crust so that the crustal radiogenic component of heat...
Geophysical evidence for the intersection of the St Paul, Cape Palmas and Grand Cess fracture zones with the continental margin of Liberia, West Africa
John C. Behrendt, J. Schlee, James M. Robb
1974, Nature (248) 324-326
PUBLISHED reconstructions of Gondwana continent1 (Fig. la) show a gap in fit near the junction of the Americas and Africa. To study this critical area, the Unitedgeo I made geophysical measurements and collected rock samples across the continental margin of Liberia (USGS-IDOE cruise leg 5) in November...
Oil shale development and its environmental considerations
R.T. Stone, H. Johnson, A. Decora
1974, Conference Paper, Preprints
The petroleum shortage recently experienced by many nations throughout the world has created an intense interest in obtaining new and supplemental energy sources. In the United States, this interest has been centered on oil shale. Any major action by the federal government having significant environmental effects requires compliance with the...