Organic geothermometry of petroleum from Escanaba Trough, offshore northern California
Keith A. Kvenvolden, John B. Rapp, Frances D. Hostettler, J. David, George E. Claypool
1988, Organic Geochemistry (13) 351-355
We have measured the extent of hopane and sterane isomerization and of monoaromatic-steroid-hydrocarbon aromatization in a sample of hydrothermally derived petroleum from the Escanaba Trough, a sediment-covered, volcanically active ridge axis. The results, along with kinetic parameters, predict the possible time-temperature history of the petrolum-forming process for this sample. The...
A note on the recent natural gradient tracer test at the Borden Site
R.L. Naff, T.-C. Jim Yeh, M.W. Kemblowski
1988, Water Resources Research (24) 2099-2103
The variance in particle position, a measure of dispersion, is reviewed in the context of certain models of flow in random porous media. Asymptotic results for a highly stratified medium and an isotropic medium are particularly highlighted. Results of the natural gradient tracer test at the Borden site are reviewed...
A test of uranium-series dating of fossil tooth enamel: Results from Tournal Cave, France
J. L. Bischoff, R.J. Rosenbauer, A. Tavoso, Henry de Lumley
1988, Applied Geochemistry (3) 145-151
A series of well preserved mammal bones and horse teeth was analyzed from archaeological levels of Tournal Cave (Magdalenian, Aurignacian, and Mousterain) to test the hypothesis that well-crystallized enamel behaves more as a closed system than does whole bone. The isotopic...
Seismic stratigraphy and late Quaternary shelf history, south-central Monterey Bay, California
J. L. Chin, H.E. Clifton, H.T. Mullins
1988, Marine Geology (81) 137-157
The south-central Monterey Bay shelf is a high-energy, wave-dominated, tectonically active coastal region on the central California continental margin. A prominent feature of this shelf is a sediment lobe off the mouth of the Salinas River that has surface expression.High-resolution seismic-reflection profiles reveal that an angular...
High-resolution 40Ar 39Ar chronology of Oligocene volcanic rocks, San Juan Mountains, Colorado
M. A. Lanphere
1988, Geochimica et Cosmochimica Acta (52) 1425-1434
The central San Juan caldera complex consists of seven calderas from which eight major ash-flow tuffs were erupted during a period of intense volcanic activity that lasted for approximately 2 m.y. about 26–28 Ma. The analytical precision of conventional K-Ar dating in this time interval is not sufficient to unambiguously...
Radarclinometry: Bootstrapping the radar reflectance function from the image pixel-signal frequency distribution and an altimetry profile
R.L. Wildey
1988, Earth, Moon and Planets (41) 223-240
A method is derived for determining the dependence of radar backscatter on incidence angle that is applicable to the region corresponding to a particular radar image. The method is based on enforcing mathematical consistency between the frequency distribution of the image's pixel signals (histogram of DN values with suitable normalizations)...
Statistical Methods and Sampling Design for Estimating Step Trends in Surface-Water Quality
Robert M. Hirsch
1988, Water Resources Bulletin (24) 493-503
This paper addresses two components of the problem of estimating the magnitude of step trends in surface water quality. The first is finding a robust estimator appropriate to the data characteristics expected in water-quality time series. The J. L. Hodges-E. L. Lehmann class of estimators is found to be robust...
Columbia Bay, Alaska: An 'upside down' estuary
R. A. Walters, E.G. Josberger, C. L. Driedger
1988, Estuarine, Coastal and Shelf Science (26) 607-617
Circulation and water properties within Columbia Bay, Alaska, are dominated by the effects of Columbia Glacier at the head of the Bay. The basin between the glacier terminus and the terminal moraine (sill depth of about 22 m) responds as an ‘upside down’ estuary with the subglacial discharge of freshwater...
Leaching characteristics of a high-calcium fly ash as a function of pH: A potential source of selenium toxicity
D.A. Grisafe, E.E. Angino, S. M. Smith
1988, Applied Geochemistry (3) 601-608
Using a modified extraction procedure, the effect of pH on the leaching of selected elements from Ca-rich (Type C) power plant fly ash was studied. Continuous additions of acetic acid were used to maintain pH values of fly ash slurries at...
Paleoecology of Middle Pennsylvanian-age peat-swamp plants in Herrin coal, Kentucky, U.S.A.
R.B. Winston
1988, International Journal of Coal Geology (10) 203-238
To develop a method for quantifying the vegetation of Pennsylvania-age coal beds, of four coal-ball (permineralized peat) profiles and four coal column samples from the Herrin coal bed (Kentucky No. 11) Carbondale Formation in western Kentucky were compared. An estimated 89.5%...
Origin of conglomerate stratigraphy in the Franciscan assemblage and Great Valley sequence, northern California
V.M. Seiders
1988, Geology (16) 783-787
In the northern California Coast Ranges, the forearc-basin Great Valley sequence of Late Jurassic and Cretaceous age contains three distinctive types of conglomerate: (1) chert-rich conglomerate of Tithonian to Valanginian age, (2) volcanic-rich conglomerate of mainly Valanginian age, and (3) mixed-clast conglomerate of...
Oxygen isotope variations in granulite-grade iron formations: constraints on oxygen diffusion and retrograde isotopic exchange
Z.D. Sharp, J. R. O’Neil, E.J. Essene
1988, Contributions to Mineralogy and Petrology (98) 490-501
The oxygen isotope ratios of various minerals were measured in a granulite-grade iron formation in the Wind River Range, Wyoming. Estimates of temperature and pressure for the terrane using well calibrated geothermometers and geobarometers are 730??50?? C and 5.5??0.5 kbar. The mineral constraints on fluid compositions in the iron formation...
The plumbotectonic model for Pb isotopic systematics among major terrestrial reservoirs: A case for bi-directional transport
R. E. Zartman, S.M. Haines
1988, Geochimica et Cosmochimica Acta (52) 1327-1339
Version IV of plumbotectonics expands and refines the original model of Doe and Zartman (1979) and Zartman and Doe (1981) for explaining Pb (Sr, and Nd) isotopic systematics among major terrestrial reservoirs. A case for bi-directional transport among reservoirs is based on the observed isotopic compositions for different tectonic settings, and finds a rationale...
Thermal modelling of stepwise anatexis in a thrust-thickened sialic crust
E-An Zen
1988, Transactions of the Royal Society of Edinburgh, Earth Sciences (79) 223-235
One-dimensional modelling of the thermal history of a sialic crust thickened by multiple overstack thrusting of upper crustal material shows that anatexis is likely. both the uplift rate and the length of the incubation period between end of tectonism and start of uplift are important controls on the amount and...
A tentative protocol for measurement of radon availability from the ground
A.B. Tanner
1988, Northeastern Environmental Science (7) 58-62
A procedure is being tested in order to determine its suitability for assessing the intrinsic ability of the ground at a particular site to supply radon (222Rn) to a basement structure to be built on the site. The mean migration distance, multiplied by the measured radon concentration gives the "Radon...
Climatological observations and predicted sublimation rates at Lake Hoare, Antarctica.
G.D. Clow, C.P. McKay, G.M. Simmons Jr., R.A. Wharton Jr.
1988, Journal of Climate (1) 715-728
In December 1985, an automated meteorological station was established at Lake Hoare in the dry valley region of Antarctica. Here, we report on the first year-round observations available for any site in Taylor Valley. This dataset augments the year-round data obtained at Lake Vanda (Wright Valley) by winter-over crews during...
Atmospheric deposition effects on the chemistry of a stream in Northeastern Georgia
G. R. Buell, N.E. Peters
1988, Water, Air, & Soil Pollution (39) 275-291
The quantity and quality of precipitation and streamwater were measured from August 1985 through September 1986 in the Brier Creek watershed, a 440-ha drainage in the Southern Blue Ridge Province of northeastern Georgia, to determine stream sensitivity to acidic deposition. Precipitation samples collected at 2 sites had a volume-weighted average...
Trends in lead concentrations in major U.S. rivers and their relation to historical changes in gasoline-lead consumption
R. B. Alexander, R. A. Smith
1988, Water Resources Bulletin (24)
Declines in concentrations of dissolved lead occurred at nearly two-thirds of 306 locations on major U.S. rivers from 1974 to 1985. Declines in dissolved lead concentrations are statistically significant (p < 0.10) at approximately one-third of the sampling locations. Statistically significant increases in dissolved lead concentrations occurred at only 6...
Regression estimates for topological‐hydrograph input
Michael R. Karlinger, D. Phillip Guertin, Brent M. Troutman
1988, Journal of Water Resources Planning and Management (114) 446-456
Physiographic, hydrologic, and rainfall data from 18 small drainage basins in semiarid, central Wyoming were used to calibrate topological, unit‐hydrograph models for celerity, the average rate of travel of a flood wave through the basin. The data set consisted of basin characteristics and hydrologic data for the 18 basins and...
Late Cenozoic offsets on the offshore connection between the Fairweather and Queen Charlotte faults off southeast Alaska
P.R. Carlson, T.R. Bruns, George Plafker
1988, Marine Geology (85) 89-97
Closely spaced seismic reflection profiles permit us to extend the onshore Fairweather fault across the continental margin off southeast Alaska to the Queen Charlotte fault. Evidence for Quaternary movement along this major plate boundary includes 20–40-m high sea-floor scarps, offset subsurface...
Groundwater flow and transport modeling
Leonard F. Konikow, J.W. Mercer
1988, Journal of Hydrology (100) 379-409
Deterministic, distributed-parameter, numerical simulation models for analyzing groundwater flow and transport problems have come to be used almost routinely during the past decade. A review of the theoretical basis and practical use of groundwater flow and solute transport models is used to illustrate...
Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California
Roger Fujii, S. J. Deverel, D. B. Hatfield
1988, Soil Science Society of America Journal (52) 1274-1283
Soils from three agricultural fields in the Panoche Creek alluvial fan area in the western San Joaquin Valley, California, were analyzed for soluble, adsorbed, and total concentrations of selenium (Se) to assess the distribution and forms of Se in relation to the leaching of Se from soils. This assessment is...
The potential for catastrophic dam failure at Lake Nyos maar, Cameroon
J. P. Lockwood, J. E. Costa, M. L. Tuttle, J. Nni, S.G. Tebor
1988, Bulletin of Volcanology (50) 340-349
The upper 40 m of Lake Nyos is bounded on the north by a narrow dam of poorly consolidated pyroclastic rocks, emplaced during the eruptive formation of the Lake Nyos maar a few hundred years ago. This 50-m-wide natural dam is structurally weak and is being eroded at an uncertain,...
Wetland Boundary Determination in the Great Dismal Swamp Using Weighted Averages
Virginia Carter, Mary Keith Garrett, Patricia T. Gammon
1988, Water Resources Bulletin (24) 297-306
A weighted average method was used to analyze transition zone vegetation in the Great Dismal Swamp to determine if a more uniform determination of wetland boundaries can be made nationwide. The method was applied to vegetation data collected on four transects and three vertical layers across the wetland-to-upland transition zone...
The radiocarbon budget for Mono Lake: An unsolved mystery
W.S. Broecker, R. Wanninkhof, G. Mathieu, T.-H. Peng, S. Stine, S. Robinson, A. Herczeg, M. Stuiver
1988, Earth and Planetary Science Letters (88) 16-26
Since 1957 the 14C/C ratio of the dissolved inorganic carbon in Mono Lake has risen by about 60‰. The magnitude of this increase is about four times larger than that expected from the invasion of bomb-produced14C from the atmosphere. We have eliminated the following explanations: (1) measurement error, (2) an unusually...
