Big Soda Lake (Nevada). 2. Pelagic sulfate reduction
Richard L. Smith, Ronald S. Oremland
1987, Limnology and Oceanography (32) 794-803
The epilimnion of hypersaline, alkaline, meromictic Big Soda Lake contains an average 58 mmol sulfate liter−1 and 0.4 µmol dissolved iron liter−1. The monimolimnion, which is permanently anoxic, has a sulfide concentration ranging seasonally from 4 to 7 mmol liter−1. Depth profiles of sulfate reduction in the monimolimnion, assayed with a 35S tracer...
Response of wetland herbaceous communities to gradients of light and substrate following disturbance by thermal pollution
Christopher P. Dunn, Michael L. Scott
1987, Vegetatio (70) 119-124
The influence of thermal disturbance and site characteristics on distribution of herbs was studied in portions of a 3020 ha wetland in the southeastern USA. Presence-absence of 52 species in 130 0.25 m2 plots was determined from four sites with different disturbance histories and from an undisturbed site. Data from...
The 1875 eruption of Askja volcano, Iceland: Combined fractional crystallization and selective contamination in the generation of rhyolitic magma
R. Macdonald, R.S.J. Sparks, H. Sugurdsson, D.P. Mattey, D.W. Mcgarvie, R.L. Smith
1987, Mineralogical Magazine (51) 183-202
Major and trace element and Sr, Nd and O isotopic data are presented for ferrobasalts, icelandites, rhyolites, mixed pumices and silicic xenoliths of the 1875 eruption of Askja. Trace element modelling and Sr and Nd data largely confirm previous major element calculations that fractional crystallization was dominant in the generation...
Propogation of tides in south, central and San Pablo Bays, California - comparison of model results and field observations
J. W. Gartner, R. T. Cheng
1987, Conference Paper, Proceedings, workshop on hydrodynamics of San Francisco Bay/delta
Petrology and geochemistry of alkali gabbronorites from Lunar Breccia 67975
O.B. James, M.M. Lindstrom, M.K. Flohr
1987, Journal of Geophysical Research B: Solid Earth (92) 314-330
Clasts of an unusual type of lunar highlands igneous rock, alkali gabbronorite, have been found in Apollo 16 breccia 67975. The alkali gabbronorites form two distinct subgroups, magnesian and ferroan. Modes and bulk compositions are highly varied. The magnesian alkali gabbronorites are composed of bytownitic plagioclase (OrAn), hypersthene (WoEn), augite...
A geologic interpretation of seismic-refraction results in northeastern California
Gary S. Fuis, J.J. Zucca, Walter D. Mooney, Bernd Milkereit
1987, GSA Bulletin (98) 53-65
In 1981, the U.S. Geological Survey conducted a seismic-refraction experiment in northeastern California designed to study the Klamath Mountains, Cascade Range, Modoc Plateau, and Basin and Range provinces. Key profiles include 135-km-long, north-south lines in the Klamath Mountains and Modoc Plateau provinces and a 260-km-long, east-west line crossing all of...
15N/14N variations in Cretaceous Atlantic sedimentary sequences: Implication for past changes in marine nitrogen biogeochemistry
Greg H. Rau, M.A. Arthur, Walter E. Dean
1987, Earth and Planetary Science Letters (82) 269-279
At two locations in the Atlantic Ocean (DSDP Sites 367 and 530) early to middle Cretaceous organic-carbon-rich beds (“black shales”) were found to have significantly lower δ15N values (lower15N/14N ratios) than adjacent organic-carbon-poor beds (white limestones or green claystones). While these lithologies are of marine origin, the black strata in...
Shocked quartz in the Cretaceous-Tertiary boundary clays: Evidence for a global distribution
Bruce F. Bohor, P.J. Modreski, Eugene E. Foord
1987, Science (236) 705-709
Shocked quartz grains displaying planar features were isolated from Cretaceous- Tertiary boundary clays at five sites in Europe, a core from the north-central Pacific Ocean, and a site in New Zealand. At all of these sites, the planar features in the shocked quartz can be indexed to rational crystallographic planes...
Quantitative studies of biodegradation of petroleum and some model hydrocarbons in ground water and sediment environments: Chapter 20
Fu-Hsian Chang, M. F. Hult, N.N. Noben
Deborah M. Fairchild, editor(s)
1987, Book chapter, Ground-water quality and agricultural practices
No abstract available....
Applications of spatial postclassification models
Eugene A. Fosnight
1987, Conference Paper, Proceedings of the 21st International Symposium on Remote Sensing of Environment
No abstract available....
Remote sensing of the Fram Strait marginal ice zone
R.A. Shuchman, B.A. Burns, O.M. Johannessen, E.G. Josberger, W. J. Campbell, T.O. Manley, N. Lannelongue
1987, Science (236) 429-431
Sequential remote sensing images of the Fram Strait marginal ice zone played a key role in elucidating the complex interactions of the atmosphere, ocean, and sea ice. Analysis of a subset of these images covering a 1-week period provided quantitative data on the mesoscale ice morphology, including ice edge positions,...
Increased solubility of quartz in water due to complexing by organic compounds
P. Bennett, D. I. Siegel
1987, Nature (326) 684-686
Quartz is the most stable natural solid phase of silica. It weathers extremely slowly at the Earth's surface1, and often resists weathering even after all other silicate minerals have been degraded. However, there is ample evidence from both ancient and modern environments indicating enhanced dissolution and mobility of silica under...
Velocity control as a tool for optimal plume containment in the Equus Beds aquifer, Kansas
M. Heidari, J. Sadeghipour, O. Drici
1987, Journal of the American Water Resources Association (23) 325-335
A ground-water-management model was developed to investigate the best management options for the containment of an oil-field-brine plume in the Equus Beds aquifer in south-central Kansas. The main purpose of the management model was to find the optimal locations and minimum rates of pumpage of a set...
Community models for wildlife impact assessment: a review of concepts and approaches
Richard L. Schroeder
1987, Report, Biological Report
The first two sections of this paper are concerned with defining and bounding communities, and describing those attributes of the community that are quantifiable and suitable for wildlife impact assessment purposes. Prior to the development or use of a community model, it is important to have a clear understanding...
The Husting dilemma: A methodological note
James D. Nichols, Gary R. Hepp, Kenneth H. Pollock, James E. Hines
1987, Ecology (68) 213-217
Recently, Gill (1985) discussed the interpretation of capture history data resulting from his own studies on the red-spotted newt, Notophthalmus viridescens , and work by Husting (1965) on spotted salamanders, Ambystoma maculatum. Gill (1985) noted that gaps in capture histories (years in which individuals were not captured, preceded and...
I. Thermal evolution of Ganymede and implications for surface features. II. Magnetohydrodynamic constraints on deep zonal flow in the giant planets. III. A fast finite-element algorithm for two-dimensional photoclinometry
Randolph L. Kirk
1987, Thesis
The work is divided into three independent papers:PAPER I:Thermal evolution models are presented for Ganymede, assuming a mostly differentiated initial state of a water ocean overlying a rock layer. The only heat sources are assumed to be primordial heat (provided by accretion) and the long-lived radiogenic heat sources in the...
Analysis of trends in water-quality data for water conservation area 3A, the Everglades, Florida
Harold C. Mattraw Jr., Daniel J. Scheidt, Anthony C. Federico
1987, Water-Resources Investigations Report 87-4142
Rainfall and water-quality data bases from the South Florida Water Management District were used to evaluate water quality trends at 10 locations near or in Water Conservation Area 3A in The Everglades. The Seasonal Kendall test was applied to specific conductance, orthophosphate-phosphorus, nitrate-nitrogen, total Kjeldahl nitrogen, and total nitrogen regression...
Simulation of tidal flow and circulation patterns in the Loxahatchee River Estuary, southeastern Florida
Gary M. Russell, Carl R. Goodwin
1987, Water-Resources Investigations Report 87-4201
Results of a two-dimensional, vertically averaged, computer simulation model of the Loxahatchee River estuary show that under typical low freshwater inflow and vertically well mixed conditions, water circulation is dominated by freshwater inflow rather than by tidal influence. The model can simulate tidal flow and circulation in the Loxahatchee River...
Thermal evolution of a differentiated Ganymede and implications for surface features
Randolph L. Kirk, David J. Stevenson
1987, Icarus (69) 91-134
Thermal evolution models are presented for Ganymede, assuming a mostly differentiated initial state of a water ocean overlying a rock layer. The only heat sources are assumed to be primordial heat (provided by accretion) and the long-lived radiogenic heat sources in the rock component. As Ganymede cools, the ocean thins,...
Hydromagnetic constraints on deep zonal flows in the giant planets
Randolph L. Kirk, David J. Stevenson
1987, Astrophysical Journal (316) 836-846
The observed zonal flows of the giant planets will, if they penetrate below the visible atmosphere, interact significantly with the planetary magnetic field outside the metallized core. The appropriate measure of this interaction is the Chandrasekhar number Q = H^2 /4πρνα^2 λ (H = radial component of the magnetic field,...
Instream water use in the United States: water laws and methods for determining flow requirements
Berton L. Lamb, Harvey R. Doerksen
1987, Report, National Water Summary 1987
Water use generally is divided into two primary classes - offstream use and instream use. In offstream use, sometimes called out-of-stream or diversionary use, water is withdrawn (diverted) from a stream or aquifer and transported to the place of use. Examples are irrigated agriculture, municipal water supply, and industrial use....
Discussion of: 'Conceptual models of sediment transport in streams' by R. L. Beschta
Robert T. Milhous
1987, Book chapter, Sediment Transport in Gravel-Bed Rivers
No abstract available....
Prospects for Yellowstone grizzly bears
R.R. Knight, L.L. Eberhardt
1987, Bears: Their Biology and Management (7) 45-50
Recent analyses of data on the grizzly bear (Ursus arctos horribilis) population of Yellowstone National Park and its environs suggest the likelihood of a continuing decline in numbers if losses of fully adult females are not reduced. The size of the population is not known, and a simple projection model...
Breeding bird response to cattle grazing of a cottonwood bottomland
James A. Sedgwick, Fritz L. Knopf
1987, Journal of Wildlife Management (51) 230-237
We studied avian habitat relationships and the impact of grazing on breeding densities of selected migratory birds in a plains cottonwood (Populus sargentii) bottomland in northeastern Colorado. Five 16-ha plots served as controls and 5 were fenced and fall-grazed October-November 1982-84 following a season of pre-treatment study in the spring...
Incorporating activity time in harmonic home range analysis
Michael D. Samuel, Edward O. Garton
1987, Journal of Wildlife Management (51) 254-257
The amount of time an animal spends in particular areas is an important aspect of estimating its home range and activity pattern. Calculations of home range using the harmonic mean can be modified to reflect the amount of time or the type of activity observed at each location. The...
