Nearshore current pattern off south Texas: an interpretation from aerial photographs.
R. E. Hunter, G. W. Hill
1980, Remote Sensing of Environment (10) 115-134
Current patterns in a 4-km-wide zone along the south Texas coast were interpreted from patterns of water turbidity visible in aerial photographs taken during a winter day of moderate northerly winds. Features of the turbidity pattern remained recognizable on photographs taken 25 min apart. Currents measured from the movements of...
Kinetic model for the short-term dissolution of a rhyolitic glass
A. F. White, H.C. Claassen
1980, Chemical Geology (28) 91-109
Aqueous dissolution experiments with the vitric phase of a rhyolitic tuff were performed at 25??C and constant pH in the range 4.5-7.5. Results suggest interchange of aqueous hydrogen ions for cations situated both on the surface and within the glass. At time intervals from 24 to 900 hr., dissolution kinetics...
Accuracy of an estuarine hydrodynamic model using smooth elements
Roy A. Walters, Ralph T. Cheng
1980, Water Resources Research (16) 187-195
A finite element model which uses triangular, isoparametric elements with quadratic basis functions for the two velocity components and linear basis functions for water surface elevation is used in the computation of shallow water wave motions. Specifically addressed are two common uncertainties in this class of two-dimensional hydrodynamic models: the...
The morphology of the Martian surface
M. H. Carr
1980, Space Science Reviews (25) 231-284
Most of the southern hemisphere of Mars is densely cratered and stands 1-3 km above the topographic datum. The northern hemisphere is more sparsely cratered and elevations are generally below the datum. A broad rise, the Tharsis bulge, centered at 14?? S, 101?? W, is 8000 km across and 10...
Small impact craters in the lunar regolith - Their morphologies, relative ages, and rates of formation
H. J. Moore, J. M. Boyce, D.A. Hahn
1980, The Moon and the Planets (23) 231-252
Apparently, there are two types of size-frequency distributions of small lunar craters (???1-100 m across): (1) crater production distributions for which the cumulative frequency of craters is an inverse function of diameter to power near 2.8, and (2) steady-state distributions for which the cumulative frequency of craters is inversely proportional...
A three-dimensional model to predict future oil discoveries in spatially connected multiple plays
J.H. Schuenemeyer, L.J. Drew, W.J. Bawiec
1980, Journal of the International Association for Mathematical Geology (12) 459-472
A discovery-process model that had been devised previously to estimate the size distribution of oil and gas fields remaining to be discovered in a single producing horizon was adapted to a basin containing spatially connected multiple plays and producing horizons. This model used the concept of the area of influence...
Transition of basaltic lava from pahoehoe to aa, Kilauea Volcano, Hawaii: Field observations and key factors
Donald W. Peterson, Robert I. Tilling
1980, Journal of Volcanology and Geothermal Research (7) 271-293
Nearly all Hawaiian basaltic lava erupts as pahoehoe, and some changes to aa during flowage and cooling; factors governing the transition involve certain critical relations between viscosity and rate of shear strain. If the lava slows, cools, and stops in direct response to concomitant increase in viscosity before these critical...
Depositional environments of some Pleistocene coastal terrace deposits, southwestern Oregon - case history of progradational beach and dune sequence.
R. E. Hunter
1980, Sedimentary Geology (27) 241-262
These deposits comprise a basal gravelly unit and 3 overlying sandy units, each with mud beds, a paleosol, or the modern soil in its uppermost part. The gravelly unit is interpreted as a progradational deposit. The main parts of the sandy units are made up of 1) a crossbedded sand...
The Southern California uplift revisited
R. A. Kerr
1980, Earthquake Information Bulletin (USGS) (12) 98-103
The earthquake that struck Livermore, east of San Francisco, on January 24 was the second moderate earthquake to have occurred in the San Francisco Bay area in 5 months. It raised familiar questions. Does this mean that the "Big One" is coming? Is the theater of heightened concern now in...
Ocean eddy structure by satellite radar altimetry required for iceberg towing
W. J. Campbell, R. E. Cheney, J. G. Marsh, N. M. Mognard
1980, Cold Regions Science and Technology (1) 211-221
Models for the towing of large tabular icebergs give towing speeds of 0.5 knots to 1.0 knots relative to the ambient near surface current. Recent oceanographic research indicates that the world oceans are not principally composed of large steady-state current systems, like the Gulf Stream, but that most of the...
Radar, visual and thermal characteristics of Mars: Rough planar surfaces
G. G. Schaber
1980, Icarus (42) 159-184
High-resolution Viking Orbiter images (10 to 15 m/pixel) contain significant information on Martian surface roughness at 25- to 100-m lateral scales, whereas Earth-based radar observations of Mars are sensitive to roughness at lateral scales of 1 to 30 m, or more....
Paleozoic paleomagnetism and northward drift of the Alexander terrane, southeastern Alaska
R. Van Der Voo, M. Jones, C. S. Grommé, G.D. Eberlein, M. Churkin Jr.
1980, Journal of Geophysical Research Solid Earth (85) 5281-5296
Paleozoic limestone, graywacke, sandstone, milestone, red beds and volcanic rocks of the Alexander terrane, southeastern Alaska, have yielded six paleomagnetic pole positions after thermal and alternating-field demagnetization. These poles are from sample groups of late Middle Ordovician, Late Ordovician, Devonian, Late Devonian, and early and late Carboniferous age. To test...
Rare earth element distribution in some hydrothermal minerals: Evidence for crystallographic control
J. W. Morgan, G.A. Wandless
1980, Geochimica et Cosmochimica Acta (44) 973-980
Rare earth element (REE) abundances were measured by neutron activation analysis in anhydrite (CaSO4), barite (BaSO4), siderite (FeCO3) and galena (PbS). A simple crystal-chemical model qualitatively describes the relative affinities for REE substitution in anhydrite, barite, and siderite. When normalized to ‘crustal’ abundances (as an approximation to the hydrothermal fluid...
Computational methods for a three-dimensional model of the petroleum-discovery process
J.H. Schuenemeyer, W.J. Bawiec, L.J. Drew
1980, Computers & Geosciences (6) 323-360
A discovery-process model devised by Drew, Schuenemeyer, and Root can be used to predict the amount of petroleum to be discovered in a basin from some future level of exploratory effort: the predictions are based on historical drilling and discovery data. Because marginal costs of discovery and production are a...
Circular current loops, magnetic dipoles and spherical harmonic analysis.
L.R. Alldredge
1980, Journal of Geomagnetism & Geoelectricity (32) 357-364
Spherical harmonic analysis (SHA) is the most used method of describing the Earth's magnetic field, even though spherical harmonic coefficients (SHC) almost completely defy interpretation in terms of real sources. Some moderately successful efforts have been made to represent the field in terms of dipoles placed in the core in...
Speculations on processes responsible for mesoscale current lineations on the continental shelf, southern California
Herman A. Karl
1980, Marine Geology (34) M9-M18
A side-scan sonar survey of San Pedro shelf, California, reveals areas of mesoscale current lineations oriented approximately north-northeast in water depths of 20-25 m. Widths of sand ribbons range from 40 to 120 m and intervening erosional furrows, from 15 to 50 m. A conceptual model shows that the scale...
Implications of regional gravity for state of stress in the earth's crust and upper mantle
M. McNutt
1980, Journal of Geophysical Research Solid Earth (85) 6377-6396
Topography is maintained by stress differences within the earth. Depending on the distribution of the stress we classify the support as either local or regional compensation. In general, the stresses implied in a regional compensation scheme are an order of magnitude larger than those corresponding to local isostasy. Gravity anomalies,...
Mixing models and ionic geothermometers applied to warm (up to 60°C) springs: Jordan Rift Valley, Israel
E. Mazor, D. Levitte, A.H. Truesdell, J. Healy, A. Nissenbaum
1980, Journal of Hydrology (45) 1-19
Mixing models and evaluation of SiO2 contents of warm-water manifestations in the Jordan—Dead Sea Rift Valley indicate that these waters are fed by aquifers with estimated temperatures of up to 68°C. These calculations and Na/K ratios, concentrations of Na, K and Ca, concentrations of atmospheric Ne, Ar, Kr and Xe;...
Nd-isotopes in selected mantle-derived rocks and minerals and their implications for mantle evolution
A. R. Basu, M. Tatsumoto
1980, Contributions to Mineralogy and Petrology (75) 43-54
The Sm-Nd systematics in a variety of mantle-derived samples including kimberlites, alnoite, carbonatite, pyroxene and amphibole inclusions in alkali basalts and xenolithic eclogites, granulites and a pyroxene megacryst in kimberlites are reported. The additional data on kimberlites strengthen our earlier conclusion that kimberlites are derived from a relatively undifferentiated chondritic...
Trace metal bioavailability: Modeling chemical and biological interactions of sediment-bound zinc
S. N. Luoma, G.W. Bryan
Everett A. Jenne, editor(s)
1979, Book chapter, Chemical Modeling in Aqueous Systems
Extractable concentrations of sediment-bound Zn, as modified by the physicochemical form of the metal in the sediments, controlled Zn concentrations in the deposit-feeding bivalvesScrobicularia plana (collected from 40 stations in 17 estuaries in southwest England) andMacoma balthica (from 28 stations in San Francisco Bay). Over a wide range of concentrations,...
A digital model for simulation of ground-water hydrology in the Houston area, Texas
Walter R. Meyer, Jerry E. Carr
1979, Limited Printing Report 103
This report documents the construction and calibration of a digital model for the simulation of hydrologic conditions in the Chicot and Evangeline aquifers in the Houston area of southeastern Texas. The model is a five-layer finite-difference model, with a grid pattern of 63 x 67 nodes representing an area of...
Water quality of Livingston Reservoir on the Trinity River, southeastern Texas
Jack Rawson
1979, Texas Department of Water Resources Report 230
The concentrations of dissolved solids, chloride, and sulfate in Livingston Reservoir on the Trinity River in southeastern Texas usually average less than 250 mg/l (milligrams per liter), 40 mg/l, and 50 mg/l, respectively. The water is usually hard or moderately hard (61 to 180 mg/l as calcium carbonate). The concentrations...
Preliminary summary of the U.S. Geological Survey strong-motion records from the October 15, 1979 Imperial Valley earthquake
R. L. Porcella, R.B. Matthiesen
1979, Open-File Report 79-1654
This report summarizes the data from near-in strong-motion accelerograph stations operated by the U.S. Geological Survey in the Imperial Valley of California at the time of the October 15, 1979 Imperial Valley earthquake. The purpose of this report is to alert others as to the nature of the strong-motion data...
Diet-related die-off of captive black-crowned night herons
J. W. Carpenter, J. W. Spann, M.N. Novilla
1979, American Association of Zoo Veterinarians, Annual Proceedings (1979) 51-55
Several species of herons, which are top-level consumers in aquatic food chains, have experienced population declines in certain areas o f their normal range (7,13) -- areas in which elevated levels of various environmental pollutants are known to occur. (6) To determine the effects of environmental contaminants on the Ardeidae,...
Population ecology of house mice in unstable habitats
L.F. Stickel
1979, Journal of Animal Ecology (48) 871-887
(1) The relationships between habitat change and house mouse populations were studied by monthly live trapping in a corn-wheat-hay rotation on a small Maryland farm. (2) Population density reached 53.0/ha in a wheat/hay field in October and 25.4/ha in corn in September. Populations increased by immigration as wheat or corn...
