Conceptual model for origin of abnormally pressured gas accumulations in low-permeability reservoirs
B. E. Law, W. W. Dickinson
1985, American Association of Petroleum Geologists Bulletin (69) 1295-1304
The largest gas fields in the Rocky Mountain region occur in abnormally pressured reservoirs. These gas accumulations are different from more conventional gas accumulations in that they are commonly located in basin-center positions, they occur downdip from water-bearing rocks, and they are in overpressured or underpressured low-permeability reservoirs. We suggest...
ANNIE - INTERACTIVE PROCESSING OF DATA BASES FOR HYDROLOGIC MODELS.
Alan M. Lumb, John L. Kittle
1985, Conference Paper
ANNIE is a data storage and retrieval system that was developed to reduce the time and effort required to calibrate, verify, and apply watershed models that continuously simulate water quantity and quality. Watershed models have three categories of input: parameters to describe segments of a drainage area, linkage of the...
Effects of the 1983 Coalinga, California, earthquake on creep along the San Andreas fault
Gerald M. Mavko, Sandra Schulz, Beth D. Brown
1985, Bulletin of the Seismological Society of America (75) 475-489
The M//L approximately equals 6. 5 earthquake that occurred near Coalinga, California, on May 2, 1983 induced changes in near-surface fault slip along the San Andreas fault. Coseismic steps were observed by creepmeters along a 200-km section of the San Andreas. some of the larger aftershocks induced additional steps, both...
NATIONAL WATER INFORMATION SYSTEM OF THE U. S. GEOLOGICAL SURVEY.
Melvin D. Edwards
1985, Conference Paper
National Water Information System (NWIS) has been designed as an interactive, distributed data system. It will integrate the existing, diverse data-processing systems into a common system. It will also provide easier, more flexible use as well as more convenient access and expanded computing, dissemination, and data-analysis capabilities. The NWIS is...
A general earthquake-observation system (GEOS)
R. D. Borcherdt, Joe B. Fletcher, E.G. Jensen, G.L. Maxwell, J.R. VanSchaack, R.E. Warrick, E. Cranswick, M.J.S. Johnston, R. McClearn
1985, Bulletin of the Seismological Society of America (75) 1783-1825
Microprocessor technology has permitted the development of a General Earthquake-Observation System (GEOS) useful for most seismic applications. Central-processing-unit control via robust software of system functions that are isolated on hardware modules permits field adaptability of the system to a wide variety of active and passive seismic experiments and straightforward modification...
Instability model for recurring large and great earthquakes in southern California
W.D. Stuart
1985, Pure and Applied Geophysics PAGEOPH (122) 793-811
The locked section of the San Andreas fault in southern California has experienced a number of large and great earthquakes in the past, and thus is expected to have more in the future. To estimate the location, time, and slip of the next few earthquakes, an earthquake instability model is...
EARTHQUAKE HAZARDS IN THE OFFSHORE ENVIRONMENT.
Robert A. Page, Peter W. Basham
1985, Ocean science and engineering (10) 195-352
This report discusses earthquake effects and potential hazards in the marine environment, describes and illustrates methods for the evaluation of earthquake hazards, and briefly reviews strategies for mitigating hazards. The report is broadly directed toward engineers, scientists, and others engaged in developing offshore resources. The continental shelves have become a...
Thickness of ice on perennially frozen lakes
C.P. McKay, G.D. Clow, R.A. Wharton Jr., S. W. Squyres
1985, Nature (313) 561-562
The dry valleys of southern Victoria Land, constituting the largest ice-free expanse in the Antarctic, contain numerous lakes whose perennial ice cover is the cause of some unique physical and biological properties 1-3. Although the depth, temperature and salinity of the liquid water varies considerably from lake to lake, the...
Determination of elastic wave velocity and relative hypocenter locations using refracted waves. I. Methodology
Kaye M. Shedlock, Steven W. Roecker
1985, Bulletin of the Seismological Society of America (75) 415-426
An arrival time difference method utilizing refracted arrivals from earthquakes in a homogeneous, layered earth model has been developed for the simultaneous determination of near-source (in situ) velocity and relative locations of earthquakes. The method is particularly applicable when analyzing data from arrays in which most of the recording stations...
Interpretation with a Donnan-based concept of the influence of simple salt concentration on the apparent binding of divalent ions to the polyelectrolytes polystyrenesulfonate and dextran sulfate
J.A. Marinsky, Robert F. Baldwin, M.M. Reddy
1985, Journal of Physical Chemistry (89) 5303-5307
It has been shown that the apparent enhancement of divalent metal ion binding to polyions such as polystyrenesulfonate (PSS) and dextran sulfate (DS) by decreasing the ionic strength of these mixed counterion systems (M2+, M+, X-, polyion) can be anticipated with the Donnan-based model developed by one of us (J.A.M.)....
Time scales of circulation and mixing processes of San Francisco Bay waters
R. A. Walters, R. T. Cheng, T. J. Conomos
1985, Hydrobiologia (129) 13-36
Conceptual models for tidal period and low-frequency variations in sea level, currents, and mixing processes in the northern and southern reaches of San Francisco Bay describe the contrasting characteristics and dissimilar processes and rates in these embayments: The northern reach is a partially mixed estuary whereas the southern reach...
Genesis and evolution of water in a two-mica pluton: A hydrogen isotope study
R. H. Brigham, J. R. O’Neil
1985, Chemical Geology (49) 159-177
Measurements were made of the hydrogen isotope composition of 74 samples of muscovite, biotite, vein quartz and whole rocks from the Papoose Flat pluton, eastern California, U.S.A., and adjacent metamorphic and sedimentary rocks in order to elucidate the genesis and evolution of water and hydrous minerals in a two-mica granodiorite....
Subdivision of thick sedimentary units into layers for simulation of groundwater flow
J. S. Weiss, A. K. Williamson
1985, Groundwater (23) 767-774
Subdividing thick sedimentary units into model layers based solely on stratigraphy can lead to serious violation of groundwater flow modeling restraints and produce erroneous results. Borehole geophysical data can be used to suggest relative permeabilities and delineate model layers that are more likely to have uniform hydraulic properties than layers...
Franciscan complex calera limestones: Accreted remnants of farallon plate oceanic plateaus
J.A. Tarduno, M. McWilliams, M.G. Debiche, W.V. Sliter, M.C. Blake
1985, Nature (317) 345-347
The Calera Limestone, part of the Franciscan Complex of northern California, may have formed in a palaeoenvironment similar to Hess and Shatsky Rises of the present north-west Pacific1. We report here new palaeomagnetic results, palaeontological data and recent plate-motion models that reinforce this assertion. The Calera Limestone may have formed...
Germanium geochemistry and mineralogy
L.R. Bernstein
1985, Geochimica et Cosmochimica Acta (49) 2409-2422
Germanium is enriched in the following geologic environments:1.(1) iron meteorites and terrestrial iron-nickel;2.(2) sulfide ore deposits, particularly those hosted by sedimentary rocks;3.(3) iron oxide deposits;4.(4) oxidized zones of Ge-bearing sulfide deposits;5.(5) pegmatites, greisens, and skarns; and6.(6) coal...
Cleavage strain in the Variscan fold belt, County Cork, Ireland, estimated from stretched arsenopyrite rosettes
M. Ford, C.C. Ferguson
1985, Journal of Structural Geology (7) 217-223
In south-west Ireland, hydrothermally formed arsenopyrite crystals in a Devonian mudstone have responded to Variscan deformation by brittle extension fracture and fragment separation. The interfragment gaps and terminal extension zones of each crystal are infilled with fibrous quartz. Stretches within the...
Modeling the rate-controlled sorption of hexavalent chromium
D.B. Grove, Kenneth G. Stollenwerk
1985, Water Resources Research (21) 1703-1709
Sorption of chromium VI on the iron-oxide- and hydroxide-coated surface of alluvial material was numerically simulated with rate-controlled reactions. Reaction kinetics and diffusional processes, in the form of film, pore, and particle diffusion, were simulated and compared with experimental results. The use of empirically calculated rate coefficients for diffusion through...
Errors and parameter estimation in precipitation-runoff modeling: 1. Theory
Brent M. Troutman
1985, Water Resources Research (21) 1195-1213
Errors in complex conceptual precipitation-runoff models may be analyzed by placing them into a statistical framework. This amounts to treating the errors as random variables and defining the probabilistic structure of the errors. By using such a framework, a large array of techniques, many of which have been presented in...
Late Holocene vegetation changes in Greenwater Valley, Mojave Desert, California
K.L. Cole, R. H. Webb
1985, Quaternary Research (23) 227-235
Small-scale late Holocene vegetation changes were determined from a series of 13 modern and fossil packrat middens collected from a site in the Greenwater Valley, northern Mojave Desert, California. Although the site is above the modern lower limit of Coleogyne ramosissima (black-brush), macrofossils of this shrub are only present in...
Coupling of ocean bottom seismometers to sediment: Results of tests with the U.S. Geological Survey ocean bottom seismometer
Anne M. Trehu
1985, Bulletin of the Seismological Society of America (75) 271-289
The response of an ocean bottom seismometer (OBS) to a transient pull that excites the natural OBS-sediment coupling resonance can be modeled as a mass-spring-dashpot system in which the resonant frequency and damping are functions of instrument mass and bearing radius and of the physical properties of the sediment (primarily...
Why deposits of longitudinal dunes are rarely recognized in the geologic record
David M. Rubin, Ralph E. Hunter
1985, Sedimentology (32) 147-157
Dunes that are morphologically of linear type, many of which are probably of longitudinal type in a morphodynamic sense, are common in modern deserts, but their deposits are rarely identified in aeolian sandstones. One reason for non-recognition of such dunes is that they can migrate laterally when they are not...
Use of strontium isotopes to constrain the timing and mode of dolomitization of upper Cenozoic sediments in a core from San Salvador, Bahamas
Peter K. Swart, Joaquin Ruiz, Charles W. Holmes
1985, Geology (15) 262-265
The 87Sr/86Sr ratios and the activity ratios of 234U/238U and 230Th/238U have been measured in dolomites from a 168-m-deep core taken on the island of San Salvador, Bahamas. These data suggest two periods of dolomitization. The first episode dolomitized Miocene age sediments during the latest Miocene, and the second dolomitized the Pliocene portion...
Dolomitization in a mixing zone of near-seawater composition, Late Pleistocene, northeastern Yucatan Peninsula
W. C. Ward, Robert B. Halley
1985, Journal of Sedimentary Research (55) 407-420
Patches of dolomite occur in cores of reefal limestone from the shallow subsurface on the northeastern coast of the Yucatan Peninsula. This limestone accumulated during an interglacial high stand of sea level about 200,000 years ago. Dolomitization was preceded by freshwater diagenesis, including...
Fluid inclusions in minerals from the geothermal fields of Tuscany, Italy
H. Belkin, B. de Vivo, G. Gianelli, P. Lattanzi
1985, Geothermics (14) 59-72
A reconnaissance study on fluid inclusions from the geothermal fields of Tuscany indicates that the hydrothermal minerals were formed by fluids which were, at least in part, boiling. Four types of aqueous inclusions were recognized: (A) two-phase (liquid + vapor) liquid...
Anomalous hydrogen emissions from the San Andreas fault observed at the Cienega Winery, central California
M. Sato, A. J. Sutton, K.A. McGee
1985, Pure and Applied Geophysics PAGEOPH (122) 376-391
We began continuous monitoring of H2 concentration in soil along the San Andreas and Calaveras faults in central California in December 1980, using small H2/O2 fuel-cell sensors. Ten monitoring stations deployed to date have shown that anomalous H2 emissions take place occasionally in addition to diurnal changes. Among the ten...
