Sand waves on an epicontinental shelf: Northern Bering Sea
Michael E. Field, C. Hans Nelson, David A. Cacchione, David E. Drake
1981, Marine Geology (32) 233-258
Sand waves and current ripples occupy the crests and flanks of a series of large linear sand ridges (20 km × 5 km × 10 m high) lying in an open-marine setting in the northern Bering Sea. The sand wave area, which lies west of Seward Peninsula and southeast of...
A numerical inversion of the Laplace transform solution to radial dispersion in a porous medium
A.F. Moench, A. Ogata
1981, Water Resources Research (17) 250-252
A special form of the numerical inversion of the Laplace transform described by Stehfest (1970) is applied to the transformed solution of dispersion in a radial flow system in a porous medium. The inversion is extremely simple to use because the weighting coefficients depend only on the number of terms...
Heavy metals and manganese oxides in the genesee watershed, New York state: Effects of geology and land use
P.R. Whitney
1981, Journal of Geochemical Exploration (14) 95-117
Manganese oxide coatings on gravels from 255 sites on tributary streams in the Genesee River Watershed were analyzed for Mn, Fe, Zn, Cd, Co, Ni, Pb, and Cu. The results were compared with data on bedrock geology, surficial geology and land use, using factor analysis and stepwise multiple regression. All...
Uranium in big sagebrush from western U.S. and evidence of possible mineralization in the Owyhee mountains of Idaho
J. A. Erdman, G.H. Harrach
1981, Journal of Geochemical Exploration (14) 83-94
Two regional studies of big sagebrush (Artemisia tridentata), a widely distributed and dominant shrub in the western United States, have shown its responsiveness to known uranium mineralization in the Monument Hill and Pumpkin Buttes districts of the southern Powder River Basin, Wyoming, and the Uravan mineral belt area in southeastern...
Arid land monitoring using Landsat albedo difference images
Charles J. Robinove, Pat S. Chavez Jr., Dale G. Gehring, Ralph Holmgren
1981, Remote Sensing of Environment (11) 133-156
The Landsat albedo, or percentage of incoming radiation reflected from the ground in the wavelength range of 0.5 [mu]m to 1.1 [mu]m, is calculated from an equation using the Landsat digital brightness values and solar irradiance values, and correcting for atmospheric scattering, multispectral scanner calibration, and sun angle. The albedo...
Depositional sequences in clastic continental slope deposits, Gulf of Mexico
A.H. Bouma
1981, Geo-Marine Letters (1) 115-121
Tertiary and Quaternary sediments, overlying diapiric older Tertiary shales and Louann Salt on the continental slope in the western Gulf of Mexico, show cyclicity based on seismic-reflection patterns. A set of indistinct parallel reflections or an acoustically semi-transparent zone, normally onlapping onto diapir flanks, alternates with a set of distinct...
Fractionation of carbon and hydrogen isotopes by methane-oxidizing bacteria
D.D. Coleman, J.B. Risatti, M. Schoell
1981, Geochimica et Cosmochimica Acta (45) 1033-1037
Carbon isotopic analysis of methane has become a popular technique in the exploration for oil and gas because it can be used to differentiate between thermogenic and microbial gas and can sometimes be used for gas-source rock correlations. Methane-oxidizing bacteria, however,...
Geology and geochemistry of gas-charged sediment on Kodiak Shelf, Alaska
M. A. Hampton, K.A. Kvenvolden
1981, Geo-Marine Letters (1) 141-147
Methane concentrations in some sediment cores from the Kodiak Shelf and adjacent continental slope increase with depth by three or four orders of magnitude and exceed the solubility in water at ambient conditions. Acoustic anomalies in seismic-reflection records imply that methane-rich sediment is widespread. Molecular composition of hydrocarbon gases and...
Geochemical evidence for modern sediment accumulation on the continental shelf off southern New England
Michael H. Bothner, E.C. Spiker, P. P. Johnson, R.R. Rendigs, P. J. Aruscavage
1981, Journal of Sedimentary Petrology (51) 281-292
An area of fine-grained sediment approximately 170 km x 74 km in size, located in water depths between 60 m and 150 m, south of Martha's Vineyard, Mass., is a site of modern sediment deposition. The 14C ages systematically increase with sediment depth from about 1,300 years B.P. at the...
Trace elemental analysis of bituminuos coals using the Heidelberg proton microprobe
J.R. Chen, H. Kneis, B. Martin, R. Nobiling, K. Traxel, E. C. T. Chao, J.A. Minkin
1981, Nuclear Instruments and Methods (181) 151-157
Trace elements in coal can occur as components of either the organic constituents (macerals) or the inorganic constituents (minerals). Studies of the concentrations and distribution of the trace elements are vital to understanding the geochemical millieu in which the coal was formed and in evaluating the attempts to recover rare...
Spectroscopy and decay dynamics of several methyl-and fluorine-substituted benzene radical cations
V.E. Bondybey, C. Vaughn, T.A. Miller, J.H. English, R.H. Shiley
1981, Journal of the American Chemical Society (103) 6303-6307
Spectra of several fluorobenzene cation radicals containing 1-3 methyl substituents were observed in solid Ne matrix and analyzed. Comparisons between these compounds and other fluorobenzenes studied previously as well as comparisons between the Β~ state lifetimes in the gas phase and in the matrix are used to gain a deeper...
Jasperoid float and stream cobbles as tools in geochemical exploration for hydrothermal ore deposits
T.G. Lovering
1981, Journal of Geochemical Exploration (14) 69-81
Fragments of silicified rocks that are associated with deposits of base and precious metals may be transported as cobbles and pebbles in alluvium far downstream from the source outcrop. These rocks commonly exhibit certain characteristics which distinguish them from other detrital siliceous material, and may thus serve as a useful...
Solubility of NaCl in aqueous electrolyte solutions from 10 to 100°C
M.A. Clynne, R.W. Potter II, J.L. Haas Jr.
1981, Journal of Chemical and Engineering Data (26) 396-398
The solubilities of NaCl in aqueous KCl, MgCl2, CaCl2, and mixed CaCl2-KCl solutions have been determined from 10 to 100??C. The data were fit to an equation, and the equation was used to calculate values of the change in solubility of NaCl, ???[NaCl]/???T. These values are required for calculations of...
Estimation of impervious-area washoff parameters
William M. Alley
1981, Water Resources Research (17) 1161-1166
In recent years many models have been developed which simulate the quality of rainfall runoff from urban areas. Common to many of these models is the use of an exponential washoff equation. This washoff equation is often modified by an availability equation to account for the effects of runoff intensity...
Magnetic signals from the core of the earth and secular variation
L.R. Alldredge
1981, Journal of Geophysical Research Solid Earth (86) 7957-7965
An oscillating, radial magnetic dipole source was assumed to exist in the core of the earth, 100 km beneath the core-mantle boundary. As an approximation, electromagnetic propagation was assumed in the core in lieu of hydromagnetic propagation, which could not be used because of unknown internal fields.Using Debye potentials, the...
Northwest margin of California continental borderland: Marine geology and tectonic evolution
J.K. Crouch
1981, American Association of Petroleum Geologists Bulletin (65) 191-218
The northwest margin of the California continental borderland consists mainly of two northwest-trending pre-Neogene lithologic belts blanketed by Miocene and younger strata. These belts, which are lithologically and structurally correlated with the Franciscan Complex and Great Valley sequence of northern California, are interpreted to represent facies corresponding to the subduction...
Blast dynamics at Mount St Helens on 18 May 1980
S. W. Kieffer
1981, Nature (291) 568-570
At 8.32 a.m. on 18 May 1980, failure of the upper part of the north slope of Mount St Helens triggered a lateral eruption ('the blast') that devastated the conifer forests in a sector covering ???500 km2 north of the volcano. I present here a steady flow model for the...
Factors affecting the partitioning of Cu, Zn and Pb in boulder coatings and stream sediments in the vicinity of a polymetallic sulfide deposit
L.H. Filipek, T. T. Chao, R.H. Carpenter
1981, Chemical Geology (33) 45-64
A sequential extraction scheme is utilized to determine the geochemical partitioning of Cu, Zn and Pb among hydrous Mn- and Fe-oxides, organics and residual crystalline silicates and oxides in the minus-80-mesh (< 0.18 mm) sediments and in boulder coatings from a stream in Lincoln County, Georgia (U.S.A.). The stream drains...
Molecular carbon isotopic evidence for the origin of geothermal hydrocarbons
D.J. Des Marais, J.H. Donchin, N.L. Nehring, A.H. Truesdell
1981, Nature (292) 826-828
Previous interest in light hydrocarbons from geothermal systems has focused principally on the origin of the methane1 and the estimation of subsurface temperatures from the carbon isotopic content of coexisting methane and carbon dioxide1-3. Higher molecular weight hydrocarbons were first reported in gases from Yellowstone National Park4, and have since...
A review of regional mineral resource assessment methods
D.A. Singer, D.L. Mosier
1981, Economic Geology (76) 1006-1015
Over 100 papers on regional mineral resource assessment of nonfuels are classified according to method(s) used and form(s) of product in order to help identify possible methods for future assessments. Types of products that have been used include: tons of metal; tons of rock and associated grade; gross value; potential;...
Comparison of automated segmented-flow and discrete analyzers for the determination of nutrients in water
V.C. Marti, D.R. Hale
1981, Environmental Science & Technology (15) 711-713
Water samples with specific conductances ranging from 66 to 6950 ??mho/cm at 25 ??C were analyzed for ammonia-N (NH3-N), nitrate plus nitrite-N (NO3 + NO2-N), nitrite-N (NO2-N), and phosphate-P (PO4-P) by using both a "segmented-flow" analyzer and a "discrete" analyzer. Plots of the discrete vs. the segmented-flow results showed linear...
Geology of central Lake Michigan
R. J. Wood, R. A. Paull, C. A. Wolosin, R. J. Friedel
1981, American Association of Petroleum Geologists Bulletin (65) 1621-1632
The geology beneath Lake Michigan between 43°00' and 44°00' N and between 86°30' and 87°40' W is interpreted from a synthesis of 1,700 km of continuous seismic reflection profile data, bathymetry, grab samples, and onshore surface and subsurface information.The continuous seismic reflection profiles and bathymetry provided information for maps of...
Dissolution of salt on the east flank of the Permian Basin in the southwestern U.S.A.
K.S. Johnson
1981, Journal of Hydrology (54) 75-93
Hydrogeologic studies prove that natural dissolution of bedded salt occurs at shallow depths in many parts of the Permian Basin of the southwestern U.S.A. This is especially well-documented on the east side of the basin in study areas on the Cimarron River and Elm Fork in western Oklahoma, and on...
Toxicity of volcanic-ash leachate to a blue-green alga. Results of a preliminary bioassay experiment
Diane M. McKnight, G. L. Feder, E.A. Stiles
1981, Environmental Science & Technology (15) 362-364
No abstract available....
Strain accumulation in southern California, 1973-1980
J.C. Savage, W.H. Prescott, M. Lisowski, N.E. King
1981, Journal of Geophysical Research Solid Earth (86) 6991-7001
Frequent surveys of seven trilateration networks in southern California over the interval 1973–1980 suggest that a regional increment in strain may have occurred in 1978–1979. Prior to 1978 and after late 1979 the strain accumulation has been predominantly a uniaxial north-south compression. This secular trend was interrupted sometime in 1978–1979...
