Role of pressure in smectite dehydration: Effects on geopressure and smectite-to-illite transformation
Virginia Colten-Bradley
1987, American Association of Petroleum Geologists Bulletin (71) 1414-1427
Evaluation of the effect of pressure on the temperature of interlayer water loss (dehydration) by smectites under diagenetic conditions indicates that smectites are stable as hydrated phases in the deep subsurface. Hydraulic and differential pressure conditions affect dehydration differently. Smectites under hydraulic pressure conditions, such as in the pores of...
The crustal structure of the axis of the Great Valley, California, from seismic refraction measurements
W.S. Holbrook, Walter D. Mooney
1987, Tectonophysics (140) 49-63
In 1982 the U.S. Geological Survey collected six seismic refraction profiles in the Great Valley of California: three axial profiles with a maximum shot-to-receiver offset of 160 km, and three shorter profiles perpendicular to the valley axis. This paper presents the results of two-dimensional raytracing and synthetic seismogram modeling of...
Stable isotope compositions and water contents of boninite series volcanic rocks from Chichi-jima, Bonin Islands, Japan
P.F. Dobson, J. R. O’Neil
1987, Earth and Planetary Science Letters (82) 75-86
Measurements of stable isotope compositions and water contents of boninite series volcanic rocks from the island of Chichi-jima, Bonin Islands, Japan, confirm that a large amount (1.6–2.4 wt.%) of primary water was present in these unusual magmas. An enrichment of 0.6‰...
GEOGRAPHIC ESTIMATION OF RUNOFF-MODEL PARAMETERS.
Arthur R. Schmidt, Linda S. Weiss, Kevin A. Oberg
1987, Conference Paper
The U. S. Geological Survey is developing techniques to estimate and evaluate unit-hydrograph and loss-rate parameter values for rainfall-runoff models using Geographic Information System (GIS) procedures. The data base includes basin, soil, and climatological characteristics that will be stored in a GIS, and unit-hydrograph and loss-rate parameters obtained from calibration...
Benthic foraminifers on the continental shelf and upper slope, Russian River area, northern California ( USA).
P. J. Quinterno, J.V. Gardner
1987, Journal of Foraminiferal Research (17) 132-152
We analyzed benthic foraminifers from 71 surface samples collected from the sea floor of the continental margin. One hundred and six different taxa were identified, and Q-mode factor analysis was used to identify assemblages. Six foraminiferal assemblage factors explain 94% of the variation in the data matrix. The Inner Shelf...
Compositional evidence regarding the origins of rims on Semarkona chondrules
J. N. Grossman, J. T. Wasson
1987, Geochimica et Cosmochimica Acta (51) 3003-3011
The compositions of the interiors and abraded surfaces of 7 chondrules from Semarkona (LL3.0) were measured by neutron activation analysis. For nonvolatile elements, the lithophile and siderophile element abundance patterns in the surfaces are generally similar to those in the corresponding interiors. Siderophile and chalcophile concentrations are much higher in...
Observations and controls on the occurrence of inherited zircon in Concord-type granitoids, New Hampshire
T.M. Harrison, J. N. Aleinikoff, W. Compston
1987, Geochimica et Cosmochimica Acta (51) 2549-2558
U-Pb analyses of zircons separated from two Concord-type plutons near Sunapee and Dixville Notch, New Hampshire, reveal differences in the pattern and magnitude of zircon inheritance which are related to differences in melt chemistry. The Sunapee pluton contains only slightly more Zr than required to saturate the melt at the...
Analysis of two-color geodimeter measurements of deformation within the Long Valley caldera: June 1983 to October 1985
J. Langbein, M. Linker, D. Tupper
1987, Journal of Geophysical Research Solid Earth (92) 9423-9442
Line length changes from several baselines in a trilateration network within the Long Valley caldera clearly define a decrease in strain rate from June 1983 through October 1985. The data consist of more than 1600 length measurements on 23 baselines using a two-color geodimeter, which has a precision of 0.2...
Probability theory versus simulation of petroleum potential in play analysis
R. A. Crovelli
1987, Annals of Operations Research (8) 363-381
An analytic probabilistic methodology for resource appraisal of undiscovered oil and gas resources in play analysis is presented. This play-analysis methodology is a geostochastic system for petroleum resource appraisal in explored as well as frontier areas. An objective was to replace an existing Monte Carlo simulation method in order to...
Gravity anomaly at a Pleistocene lake bed in NW Alaska interpreted by analogy with Greenland's Lake Taserssauq and its floating ice tongue
D.F. Barnes
1987, Journal of Geophysical Research Solid Earth (92) 8976-8984
A possible example of a very deep glacial excavation is provided by a distinctive gravity low located at the front of a valley glacier that once flowed into glacial Lake Aniuk (formerly Lake Noatak) in the western Brooks Range. Geologic and geophysical data suggest that sediments or ice filling a...
Characterization of fracture permeability with high-resolution vertical flow measurements during borehole pumping.
Frederick L. Paillet, A.E. Hess, C.H. Cheng, E. Hardin
1987, Ground Water (25) 28-40
The distribution of fracture permeability in granitic rocks was investigated by measuring the distribution of vertical flow in boreholes during periods of steady pumping. Pumping tests were conducted at two sites chosen to provide examples of moderately fractured rocks near Mirror Lake, New Hampshire and intensely fractured rocks near Oracle,...
DIGITAL CARTOGRAPHY OF THE PLANETS: NEW METHODS, ITS STATUS, AND ITS FUTURE.
R. M. Batson
1987, Photogrammetric Engineering and Remote Sensing (53) 1211-1218
A system has been developed that establishes a standardized cartographic database for each of the 19 planets and major satellites that have been explored to date. Compilation of the databases involves both traditional and newly developed digital image processing and mosaicking techniques, including radiometric and geometric corrections of the images....
Slab pull and the seismotectonics of subducting lithosphere
William Spence
1987, Reviews of Geophysics (25) 55-69
This synthesis links many seismic and tectonic processes at subduction zones, including great subduction earthquakes, to the sinking of subducted plate. Earthquake data and tectonic modeling for subduction zones indicate that the slab pull force is much larger than the ridge push force. Interactions between the forces that drive and...
Mid-Holocene climate in Northern Minnesota
R. M. Forester, L.D. Delorme, J.P. Bradbury
1987, Quaternary Research (28) 263-273
Study of Holocene ostracodes and diatoms from Elk Lake, in North-Central Minnesota, indicates that the local climate of the mid-Holocene can be subdivided into three intervals. Throughout interval 1 (ca. 7800 to 6700 yr B.P.), climate was colder and much drier than today. During intervals 2 and 3 (ca. 6700...
A model for tides and currents in the English Channel and southern North Sea
Roy A. Walters
1987, Conference Paper, Advances in Water Resources
The amplitude and phase of 11 tidal constituents for the English Channel and southern North Sea are calculated using a frequency domain, finite element model. The governing equations - the shallow water equations - are modifed such that sea level is calculated using an elliptic equation of the Helmholz type...
Cretaceous gastropods: contrasts between tethys and the temperate provinces
N. F. Sohl
1987, Journal of Paleontology (61) 1085-1111
During the Cretaceous Period, gastropod faunas show considerable differences in their evolution between the Tethyan Realm (tropical) and the Temperate Realms to the north and south. Like Holocene faunas, prosobranch gastropods constitute the dominant part of Cretaceous marine snail faunas. Entomotaeneata and opisthobranchs usually form all of...
On predicting changes in the geomagnetic field
L.R. Alldredge
1987, Journal of Geophysical Research Solid Earth (92) 6331-6338
The present method of using constant secular variation rates to forecast magnetic components at a given site or to forecast spherical harmonic coefficients is known to be inaccurate. A new predictive method using trend and trigonometric functions fitted to known past values is used to extrapolate for a few years...
Maestrichtian benthic foraminifers from Ocean Point, North Slope, Alaska ( USA).
K. McDougall
1987, Journal of Foraminiferal Research (17) 344-366
Previous studies of fauna and flora from Ocean Point, Alaska, have suggested ages ranging from Campanian to early Eocene and that these assemblages are either highly endemic or commonplace. I demonstrate that the moderately abundant benthic foraminifers constitute early Maestrichtian boreal assemblages common to Canada and northern Europe. Paleoenvironmental analysis...
Geological setting of U.S. fossil fuels.
C.D. Masters, R. F. Mast
1987, Episodes (10) 308-313
The USA has a special position in terms of fossil fuel development. Not only is it one of the most important nations in terms of resources of oil, gas and coal, but it has also been by far the dominant producer and consumer. In this thorough review of the regional...
Basin-ring spacing on the Moon, Mercury, and Mars
R.J. Pike, P. D. Spudis
1987, Earth, Moon and Planets (39) 129-194
Radial spacing between concentric rings of impact basins that lack central peaks is statistically similar and nonrandom on the Moon, Mercury, and Mars, both inside and outside the main ring. One spacing interval, (2.0 ?? 0.3)0.5D, or an integer multiple of it, dominates most basin rings. Three analytical approaches yield...
Some effects of quiet geomagnetic field changes upon values used for main field modeling
W.H. Campbell
1987, Physics of the Earth and Planetary Interiors (48) 193-199
The effects of three methods of data selection upon the assumed main field levels for geomagnetic observatory records used in main field modeling were investigated for a year of very low solar-terrestrial activity. The first method concerned the differences between the year's average of quiet day field values and the...
Coal deposits of the United States
Nelson W. John
1987, International Journal of Coal Geology (8) 355-365
The coal fields of the Unites States can be divided into six major provinces. The Appalachian and Interior Provinces contain dominantly bituminous coal in strata of Pennsylvanian age. The coal seams are relatively thin and are mined both by surface and...
APPALACHIAN FOLDS, LATERAL RAMPS, AND BASEMENT FAULTS: A MODERN ENGINEERING PROBLEM?
Howard A. Pohn
1987, Transportation Research Record 132-133
Field studies and analysis of radar data have shown that cross-strike faulting in the central and southern Appalachians has affected geologic structures at the surface. These basement faults appear to have been active through much of geologic time. Indeed, more than 45 percent of modern earthquakes occur along these narrow...
Chemical structural studies of natural lignin by dipolar dephasing solid-state 13C nuclear magnetic resonance
Patrick G. Hatcher
1987, Organic Geochemistry (11) 31-39
Two natural lignins, one from a gymnosperm wood the other from angiosperm wood, were examined by conventional solid-state and dipolar dephasing 13C nuclear magnetic resonance (NMR) techniques. The results obtained from both techniques show that the structure of natural lignins is consistent with models of softwood and hardwood lignin. The dipolar...
Modeling and analysis of direct-current electrical resistivity in the Durham Triassic basin, North Carolina
C. Erwin Brown
1987, Geoexploration (24) 429-440
Sixty-two Schlumberger electrical soundings were made in the Durham Triassic basin in an effort to determine basin structural geometry, depth of the sedimentary layers, and spatial distribution of individual rock facies. A digital computer program was used to invert the sounding curves of apparent resistivity versus distance to apparent resistivity...
