An interpretation of carbon and sulfur relationships in Black Sea sediments as indicators of environments of deposition
J.S. Leventhal
1983, Geochimica et Cosmochimica Acta (47) 133-137
Syngenetic iron sulfides in sediments are formed from dissolved sulfide resulting from sulfate reduction and catabolism of organic matter by anaerobic bacteria. It has been shown that in recent marine sediments deposited below oxygenated waters there is a constant relationship between reduced sulfur and organic carbon which is generally independent...
Geology of the head of Lydonia Canyon, U.S. Atlantic outer continental shelf
David C. Twichell
1983, Marine Geology (54) 91-108
The geology of the part of Lydonia Canyon shoreward of the continental shelf edge on the southern side of Georges Bank was mapped using high-resolution seismic-reflection and side-scan sonar techniques and surface sediment grab samples. The head of the canyon incises Pleistocene deltaic deposits and Miocene shallow marine strata. Medium...
Progressive changes in the morphology of fluvial terraces and scarps along the Rappahannock River, Virginia.
Steven M. Colman
1983, Earth Surface Processes and Landforms (8) 201-212
Progressive geomorphic changes in the flight of fluvial terraces along the Rappahannock River, Virginia, provide a framework for analysing the effect of time on landforms. Indices of terrace preservation, especially drainage densities and area to perimeter ratios, show systematic changes with terrace age. Higher scarps tend to have steeper slopes...
Human interactions with ground-water
A. Zaporozec
1983, GeoJournal (7) 427-433
Ground-Water could be considered as an immense reservoir, from which only a certain amount of water can be withdrawn without affecting the quantity and quality of water. This amount is determined by the characteristics of the environment in which ground-water occurs and by the interactions of ground-water with precipitation, surface...
Selective concentration of cesium in analcime during hydrothermal alteration, Yellowstone National Park, Wyoming
T. E. C. Keith, J. M. Thompson, R. E. Mays
1983, Geochimica et Cosmochimica Acta (47) 795-804
Chemical and mineralogical studies of fresh and hydrothermally altered rhyolitic material in Upper and Lower Geyser Basins, Yellowstone National Park, show that all the altered rocks are enriched in Cs and that Cs is selectively concentrated in analcime. The Cs content of unaltered rhyolite lava flows, including those from which...
Nonequilibrium models for predicting forms of precipitated manganese oxides
J.D. Hem, Carol J. Lind
1983, Geochimica et Cosmochimica Acta (47) 2037-2046
Manganese oxides precipitated by bubbling air through 0.01 molar solutions of MnCl2, Mn(NO3)2, MnSO4, or Mn(ClO4)2 at a constantly maintained pH of 8.5 to 9.5 at temperatures of 25°C or higher consisted mainly of hausmannite, Mn3O4. At temperatures near 0°C, but with other conditions the same, the product is feitknechtite, βMnOOH,...
Development of reaction models for ground-water systems
Niel Plummer, D.L. Parkhurst, D.C. Thorstenson
1983, Geochimica et Cosmochimica Acta (47) 665-685
Methods are described for developing geochemical reaction models from the observed chemical compositions of ground water along a hydrologic flow path. The roles of thermodynamic speciation programs, mass balance calculations, and reaction-path simulations in developing and testing reaction models are contrasted. Electron transfer is included in the mass balance equations...
Petrology and comparative thermal and mechanical histories of clasts in breccia 62236
Gordon L. Nord Jr., M.-V. Wandless
1983, Journal of Geophysical Research Solid Earth (88) A645-A657
Lunar breccia 62236 contains large lithic fragments of troctolite, norite, and anorthosite. The mafic phases, olivine, inverted pigeonite, and augite, fill interstitial areas between larger plagioclases and appear to be cumulate phases with extensive adcumulus growth. Pyroxene compositional homogeneity indicates that cation exchange during cooling was limited to an area...
Harding Iceland spar: A new δ18O−δ13C carbonate standard for hydrothermal minerals
G. P. Landis
1983, Chemical Geology (41) 91-94
An isotopically homogeneous calcite, Harding Iceland Spar (HIS), having 6180 = +11.78 ± 0.07‰ (= +22.15‰ for CO2) and δ13C = −4.80 ± 0.02‰, has been prepared in quantities suitable for use as a working standard in mass spectrometric analysis. The isotopic values are well-suited for analysis of minerals of hydrothermal...
River discharge controls phytoplankton dynamics in the northern San Francisco Bay estuary
J. E. Cloern, A.E. Alpine, B.E. Cole, R.L.J. Wong, J.F. Arthur, M.D. Ball
1983, Estuarine, Coastal and Shelf Science (16) 415-429
Phytoplankton dynamics in the upper reach of the northern San Francisco Bay estuary are usually characterized by low biomass dominated by microflagellates or freshwater diatoms in winter, and high biomass dominated by neritic diatoms in summer. During two successive years of very low river discharge (the drought of 1976-77), the...
Relationship of two lacustrine ostracode species to solute composition and salinity: Implications for paleohydrochemistry ( Limnocythere sappaensis/staplini)
R. M. Forester
1983, Geology (11) 435-438
Nonmarine ostracode species are indicative of the physical and chemical nature of lacustrine environments. Although salinity has traditionally been regarded as one of the more important parameters that affect the occurrence patterns of lacustrine ostracodes, examination of the solute composition and salinities of...
Fission track dating of kimberlitic zircons
S.E. Haggerty, E. Raber, C. W. Naeser
1983, Earth and Planetary Science Letters (63) 41-50
The only reliable method for dating kimberlites at present is the lengthy and specialized hydrothermal procedure that extracts206Pb and238U from low-uranium zircons. This paper describes a second successful method by fission track dating of large single-crystal zircons, 1.0–1.5 cm in dimension. The use of large crystals overcomes the limitations imposed...
Harmotome in a basaltic, volcaniclastic sandstone from a lacustrine deposit near Kirkland Junction, Yavapai County, Arizona
Richard A. Sheppard, Arthur J. Gude III
1983, Clays and Clay Minerals (31) 57-59
Harmotome, probably the most common of the barium-rich zeolites, has been reported from a variety of metamorphic and igneous rocks throughout the world (Deer et al., 1963). Harmotome, however, seems to be a rare authigenic constituent in sedimentary rocks, and its most common occurrence apparently is in deep-sea sediments where...
Faulting arrested by control of ground-water withdrawal in Houston, Texas
T. Holzer, R.K. Gabrysch, E.R. Verbeek
1983, Earthquake Information Bulletin (USGS) (15) 204-209
More than 86 historically active faults with an aggregate length of 150 miles have been identified within and adjacent to the Houston, Texas, metropolitan area. Although scarps of these faults grow gradually and without causing damaging earthquakes, historical fault offset has cost millions of dollars in damage to houses and...
Tectonic uplift of a middle Wisconsin marine platform near the Mendocino triple junction California
R. J. McLaughlin, K. R. Lajoie, D. H. Sorg, S.D. Morrison, J. A. Wolfe
1983, Geology (11) 35-39
An uplifted wave-cut marine platform eroded across bedrock of the Franciscan Complex at Point Delgada, northern California, is overlain by 0.5 to 5 m of wave-worked pea gravel, which is in turn directly overlain by fluvial gravel and silt deposited as alluvial fans....
Regional significance of pre-Wisconsinan till from Nantucket Island, Massachusetts
R. N. Oldale, D.M. Eskenasy
1983, Quaternary Research (19) 302-311
A major pre-Wisconsinan glacial event is the only possible source of the lower till on Nantucket Island, Massachusetts. The till occurs near the late Wisconsinan drift border and below fossiliferous marine beds of oxygen-isotope stage 5 (Sangamonian) age. It is considered to be Illinoian in age, but the evidence is...
Requirements for modeling trace metal partitioning in oxidized estuarine sediments
Samuel N. Luoma, J.A. Davis
1983, Marine Chemistry (12) 159-181
The fate of particulate-bound metals is of particular importance in estuaries because major biological energy flows involve consumption of detrital particles. The biological impact of particulate-bound metals is strongly influenced by the partitioning of metals among sediment components at the oxidized sediment-water interface. Adequate methods for directly measuring this partitioning...
Structure and petrology of the La Perouse gabbro intrusion, Fairweather Range, southeastern Alaska
R. A. Loney, G. R. Himmelberg
1983, Journal of Petrology (24) 377-423
The middle Tertiary La Perouse gabbro intrusion occurs in a Mesozoic metamorphic terrane (Chugach terrane) in the Fairweather Range, southeastern Alaska. The intrusion is 12 km wide and 27 km long, and has an exposed cumulate layering thickness of about 6000 m. The contact consists of biotite and hornblende...
Calculation of amorphous silica solubilities at 25° to 300°C and apparent cation hydration numbers in aqueous salt solutions using the concept of effective density of water
Robert O. Fournier, Marshall L. Williams
1983, Geochimica et Cosmochimica Acta (47) 587-596
The solubility of amorphous silica in aqueous salt solutions at 25° to 300°C can be calculated using information on its solubility in pure water and a model in which the activity of water in the salt solution is defined to equal the effective density. pe, of “free” water in that solution....
Mapping of hydrothermally altered rocks using airborne multispectral scanner data, Marysvale, Utah, mining district
M. H. Podwysocki, D. B. Segal, O. D. Jones
1983, Advances in Space Research (3) 101-112
Multispectral data covering an area near Marysvale, Utah, collected with the airborne National Aeronautics and Space Administration (NASA) 24-channel Bendix multispectral scanner, were analyzed to detect areas of hydrothermally altered, potentially mineralized rocks. Spectral bands were selected for analysis that approximate those of the Landsat 4 Thematic Mapper and which...
Deep-Sea Drilling Project Leg 90: The South Pacific Cenozoic
J.P. Kennett, C. Von Der Borch, P.A. Baker, C.E. Barton, A. Boersma, W.C. Dudley Jr., J.V. Gardner, D.G. Jenkins, W. Lohman, R. Morin, R. Martini, R. B. Merrill, Campbell S. Nelson, C. Robert, M.S. Srinivasan, R. Stein, A. Takeuchi
1983, Nature (303) 18-19
[No abstract available]...
Preliminary report on exclusion fencing used in combination with lethal control for managing upland waterfowl nesting habitat
R. J. Greenwood, P.M. Arnold, B.G. McGuire
1983, Report, Management of public lands in the Northern Great Plains.
Furrowed outcrops of Eocene chalk on the lower continental slop offshore New Jersey
James M. Robb, John R. Kirby, John C. Hampson, Patricia R. Gibson, Barbara Hecker
1983, Geology (11) 182-186
A sea bottom of middle Eocene calcareous claystone cut by downslope-trending furrows was observed during an Alvin dive to the mouth of Berkeley Canyon on the continental slope off New Jersey. The furrows are 10 to 50 m apart, 4 to 13 m deep, linear, and nearly parallel in water depths of...
Sedimentology of Southwestern Roads region, U.S. Virgin Islands: origin and rate of sediment accumulation
Jack L. Kindinger, Ronald J. Miller, Charles W. Holmes
1983, Journal of Sedimentary Research (53) 439-447
Sand deposits on southern insular shelf of St. Thomas, U.S. Virgin Islands, were investigated to determine their origin, environmental processes and accumulation rates. Sea-floor samples show that the sand has been derived (in situ) mainly from calcareous algae and molluscs. Zonation of the dominant sand producers is related to the...
HIGH-TEMPERATURE GEOTHERMAL RESOURCES IN HYDROTHERMAL CONVECTION SYSTEMS IN THE UNITED STATES.
Manuel Nathenson
1983, Conference Paper, Electric Power Research Institute, Advanced Power Systems Division, (Report) EPRI AP
The calculation of high-temperature geothermal resources ( greater than 150 degree C) in the United States has been done by estimating the temperature, area, and thickness of each identified system. These data, along with a general model for recoverability of geothermal energy and a calculation that takes account of the...
