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An improved method for the determination of trace levels of arsenic and antimony in geological materials by automated hydride generation–Atomic absorption spectroscopy
J.G. Crock, F.E. Lichte
1982, Analytica Chimica Acta (144) 223-233
An improved, automated method for the determination of arsenic and antimony in geological materials is described. After digestion of the material in sulfuric, nitric, hydrofluoric and perchloric acids, a hydrochloric acid solution of the sample is automatically mixed with reducing agents, acidified with additional hydrochloric acid, and treated with a...
Landsat monitoring of desert vegetation growth, 1972-1979 using a plant-shadowing model
Joseph Otterman, C.J. Robinove
1982, Advances in Space Research (2) 45-50
Landsat digital data spanning the period 1972-1979 were analyzed to monitor the status of vegetation within and outside an exclosure in the northern Sinai (precipitation 100-150 mm/year). This 6??6 km exclosure was fenced off in the summer of 1974 and subsequently has been free from the anthropogenic pressures (overgrazing, cultivation...
A model for managing sources of groundwater pollution
Steven M. Gorelick
1982, Water Resources Research (18) 773-781
The waste disposal capacity of a groundwater system can be maximized while maintaining water quality at specified locations by using a groundwater pollutant source management model that is based upon linear programing and numerical simulation. The decision variables of the management model are solute waste disposal rates at various facilities...
Gravity evidence for a shallow intrusion under Medicine Lake volcano, California
Carol A. Finn, D.L. Williams
1982, Geology (10) 503-507
A positive gravity anomaly is associated with Medicine Lake volcano, California. Trials with different Bouguer reduction densities indicate that this positive anomaly cannot be explained by an inappropriate choice of Bouguer reduction density but must be caused by a subvolcanic body. After separating...
Geometry of a mapping satellite.
J.P. Snyder
1982, Photogrammetric Engineering and Remote Sensing (48) 1593-1602
The proposed mapping satellite Mapsat is to consist of fixed fore, vertical, and aft linear detector arrays, any two of which may be used simultaneously to obtain digital images for one- dimensional stereo correlation. The satellite attitude may be varied according to Fourier series to enable a given detector on...
Obtaining maps and data from the U.S. Geological Survey
Cheryl A. Hallam
1982, Computers, Environment and Urban Systems (7) 283-294
The U.S. Geological Survey produces a variety of resource information for the United States. This includes many data bases of particular interest to planners such as land use and terrain information prepared by the National Mapping Division, water quantity and quality data collected by Water Resources Division, and coal resource...
Lead and strontium isotopes and related trace elements as genetic tracers in the Upper Cenozoic rhyolite-basalt association of the Yellowstone Plateau volcanic field
B. R. Doe, W.P. Leeman, R.L. Christiansen, C. E. Hedge
1982, Journal of Geophysical Research Solid Earth (87) 4785-4806
Supported by various field geologic and petrologic data, the contents of Pb, U, Th, Rb, and Sr and the isotopic compositions of Pb and Sr for upper Cenozoic volcanic rocks of the Yellowstone Plateau volcanic field are consistent with the hypothesis of derivation of the basaltic and rhyolitic magmas by...
Applications of Landsat imagery to problems of petroleum exploration in Qaidam Basin, China
G. B. Bailey, P. D. Anderson
1982, American Association of Petroleum Geologists Bulletin (66) 1348-1354
Tertiary and Quaternary nonmarine, petroleum-bearing sedimentary rocks in the Qaidam basin of remote western China have been extensively deformed by compressive forces. These forces created many folds which are current targets of Chinese exploration programs. Manual techniques of image analysis and interpretation were applied to computer-enhanced Landsat images of the...
Simulations of seabird damage and recovery from oilspills in the northern Gulf of Alaska.
W.B. Samuels, K.J. Lanfear
1982, Journal of Environmental Management (15) 169-182
If an oilspill contacts a colony of glaucous-winged gulls Larus hyperboreus, reducing the population by 50%, the population is expected to recover to its pre-spill level in c.20 yr. For common murres Uria aalge, this same situation yields a recovery time of c.70 yr. Assuming that oil is found in...
The modified polyconic projection for the IMW
John P. Snyder
1982, Cartographica: The International Journal for Geographic Information and Geovisualization (19) 31-43
The modified Polyconic map projection designed by Lallemand and adopted for the International Map of the World between 1909 and 1962 has two meridians and two parallels which are true to scale. Constructed geometrically in the past, forward and inverse coordinate transformations may be calculated analytically in order to transfer...
Margaritasite: a new mineral of hydrothermal origin from the Pena Blanca uranium district, Mexico.
K. J. Wenrich, P.J. Modreski, R. A. Zielinski, J. L. Seeley
1982, American Mineralogist (67) 1273-1289
Margaritasite, (Cs,K,H3O)2(UO2)2V2O8.nH2O (where Cs > K, H3O and n approx 1), a 10.514, b 8.425, c 7.25 A, beta 106.01o, P21/a, Z = 2, is a newly recognized uranium ore mineral named for the Margaritas deposit, Pena Blanca uranium district, Chihuahua, Mexico, at which it was discovered. A Cs-rich analogue...
Extreme fractionation of 234U 238U and 230Th 234U in spring waters, sediments, and fossils at the Pomme de Terre Valley, southwestern Missouri
Barney J. Szabo
1982, Geochimica et Cosmochimica Acta (46) 1675-1679
Isotopic fractionation as great as 1600% exists between 234U and 238U in spring waters, sediments, and fossils in the Pomme de Terre Valley, southwestern Missouri. The activity ratios of 234U238U">234U238U in five springs range from 7.2 to 16 in water which has been discharged for at least the...
Computation with physical values from Landsat digital data
C.J. Robinove
1982, Photogrammetric Engineering and Remote Sensing (48) 781-784
Landsat digital images are commonly analyzed by using the digital numbers for each pixel recorded on a computer-compatible magnetic tape. Although this procedure may be satisfactory when only a single, internally consistent image is used, the procedure may produce incorrect results if more than one image is used for analysis...
Geotechnical characteristics of bottom sediments in the northeastern Bering Sea.
H. W. Olsen, E.C. Clukey, C.H. Nelson
1982, Geologie en Mijnbouw (61) 91-103
Sediment of Holocene age derived from the Yukon River, consisting dominantly of silty fine sand and sandy silt, covers the bottom of central and western Norton Sound, which is a high energy environment involving extensive ice loading, high waves, and strong bottom currents. The sediment characteristics indicate that it is...
Assessment of models proposed for the 1981 revision of the IGRF
N.W. Peddie, E.B. Fabiano
1982, Journal of Geomagnetism & Geoelectricity (34) 387-392
For the second revision of the International Geomagnetic Reference Field (IGRF), the U. S. National Aeronautics and Space Administration (NASA), the U. K. Institute of Geological Sciences (IGS), and the U. S. Geological Survey (USGS) submitted proposed models of the Earth's main magnetic field at 1965.0, 1970.0, 1975.0, and 1980.0,...
An analysis of input errors in precipitation-runoff models using regression with errors in the independent variables
Brent M. Troutman
1982, Water Resources Research (18) 947-964
Errors in runoff prediction caused by input data errors are analyzed by treating precipitation-runoff models as regression (conditional expectation) models. Independent variables of the regression consist of precipitation and other input measurements; the dependent variable is runoff. In models using erroneous input data, prediction errors are inflated and estimates of...
Stratigraphy, structure, absolute age, and paleontology of the upper Pleistocene deposits at Sankaty Head, Nantucket Island, Massachusetts
Robert N. Oldale, Page C. Valentine, T. M. Cronin, E.C. Spiker, B. W. Blackwelder, D. F. Belknap, J.F. Wehmiller, Barney J. Szabo
1982, Geology (10) 246-252
The Sankaty Head cliff exposes drift of at least two glaciations and interglacial marine deposits. Radiocarbon, amino-acid- racemization, and uranium-thorium analyses were used to determine the absolute ages of the beds. The results indicate that 1) the Sankaty Sand correlates with oxygen-isotope stage 5 (Sangamonian), 2) the underlying drift is...
Geomagnetic local and regional harmonic analyses
L.R. Alldredge
1982, Journal of Geophysical Research Solid Earth (87) 1921-1926
Procedures are developed for using rectangular and cylindrical harmonic analyses in local and regional areas. Both the linear least squares analysis, applicable when component data are available, and the nonlinear least squares analysis, applicable when only total field data are available, are treated. When component data are available, it is...
Measurements of storm-generated bottom stresses on the continental shelf
D.A. Cacchione, D.E. Drake
1982, Journal of Geophysical Research - Oceans (87) 1952-1960
Large values of bottom friction velocity, u*, and roughness length, z0, determined from burst-averaged speed data taken on the continental shelf in outer Norton Sound, Alaska, with the GEOPROBE tripod during a storm in September 1977 are correlated with extremely large values of near-bottom concentration of total suspended particulate matter (TSM). Combined...
Oxygen isotope geothermometry and stability of lawsonite and pumpellyite in the Shuksan Suite, North Cascades, Washington
E. H. Brown, J. R. O’Neil
1982, Contributions to Mineralogy and Petrology (80) 240-244
Metamorphic temperatures of 330??-400?? C are inferred for rocks from the Shuksan blueschist terrane in the North Cascades, Washington. The temperatures are calculated from 18O fractionations between coexisting quartz and magnetite using the equations of Bottinga and Javoy (1973). Pressures of approximately 7 kilobars are indicated by the Jadeite content...
Nutrient exchange across the sediment-water interface in the Potomac River estuary
E. Callender, Douglas E. Hammond
1982, Estuarine, Coastal and Shelf Science (15) 395-413
The flux of ammonia, phosphate, silica and radon-222 from Potomac tidal river and estuary sediments is controlled by processes occurring at the sediment-water interface and within surficial sediment. Calculated diffusive fluxes range between 0·6 and 6·5 mmol m−2 day−1 for ammonia, 0·020 and 0·30 mmol m−2 day−1 for phosphate, and 1·3 and 3·8 mmol...
Geology of continental shelf, Onslow Bay, North Carolina, as revealed by submarine outcrops
Blake W. Blackwelder, Ian G. Macintyre, Orrin H. Pilkey
1982, American Association of Petroleum Geologists Bulletin (66) 44-56
Lithologic and stratigraphic data from rocks dredged from the continental shelf off Onslow Bay, North Carolina, provide surface control for seismic studies of the southeastern United States continental margin and help to explain the distribution of potentially economic phosphate-rich sediments on this shelf. Outcropping Miocene rocks in this area indicate...
Tourmaline in Appalachian - Caledonian massive sulphide deposits and its exploration significance.
J. F. Slack
1982, Transactions of the Institution of Mining and Metallurgy, Section B: Applied Earth Science (91) 81-89
Tourmaline is a common gangue mineral in several types of stratabound mineral deposits, including some massive base-metal sulphide ores of the Appalachian - Caledonian orogen. It is most abundant (sometimes forming massive foliated tourmalinite) in sediment-hosted deposits, such as those at the Elizabeth Cu mine and the Ore Knob Cu...
Determination of rare earth elements in geological materials by inductively coupled argon plasma/atomic emission spectrometry
J.G. Crock, F.E. Lichte
1982, Analytical Chemistry (54) 1329-1332
Inductively coupled argon plasma/optical emission spectrometery (ICAP/OES) is useful as a simultaneous, multielement analytical technique for the determination of trace elements in geological materials. A method for the determination of trace-level rare earth elements (REE) in geological materials using an ICAP 63-channel emission spectrometer is described. Separation and preconcentration of...