Petrology of the Precambrian intrusive center at Lake George, southern Front Range, Colorado
R. A. Wobus, R. S. Anderson
1978, Journal of Research of the U.S. Geological Survey (6) 81-94
The intrusive center at Lake George, at the western margin of the Pikes Peak batholith (1030 m.y.) of central Colorado, contains rocks of both the potassic and sodic differentiation trends recognized in the batholith. Finer grained variants of the Pikes Peak Granite initially formed a texturally zoned stock 8 kilometers...
Porphyry copper exploration model for northern Sonora, Mexico
Gary L. Raines
1978, Journal of Research of the U.S. Geological Survey (6) 51-58
The regional tectonic pattern of the porphyry copper province of northern Sonora, Mexico, is similar to, but more complex than, the Colorado mineral belt. Four northeast-trending shear zones, spaced at 30- to 50-kilometer intervals from Hermosillo, Mexico, north to Nogales, Mexico, are interpreted from analysis of lineament data from Landsat-1...
Hydrochemistry and hydrodynamics of injecting an iron-rich pickling liquor into a dolomitic sandstone: A laboratory study
Stephen E. Ragone, Francis S. Riley, Robert James Dingman
1978, Journal of Research of the U.S. Geological Survey (6) 1-9
Waste pickling liquor containing high concentrations of iron salts was injected into cores of quartzite, sandstone, and dolomite in a laboratory study to determine what effect this procedure might have on the permeability of these rock types. Experiments were performed at field conditions 40°C and 13.8 MPa (megapascals) in a...
A log-linear model approach to estimation of population size using the line-transect sampling method
David R. Anderson, K.P. Burnham, B.R. Crain
1978, Ecology (59) 190-193
The technique of estimating wildlife population size and density using the belt or line-transect sampling method has been used in many past projects, such as the estimation of density of waterfowl nestling sites in marshes, and is being used currently in such areas as the assessment of Pacific porpoise stocks...
Transient-pressure analysis in geothermal steam reservoirs with an immobile vaporizing liquid phase
A.F. Moench, P.G. Atkinson
1978, Geothermics (7) 253-264
A finite-difference model for the radial horizontal flow of steam through a porous medium is used to evaluate transient-pressure behavior in the presence of an immobile vaporizing or condensing liquid phase. Graphs of pressure drawdown and buildup in terms of dimensionless pressure and time are obtained for a well discharging...
Present day serpentinization in New Caledonia, Oman and Yugoslavia
I. Barnes, J. R. O’Neil, J.J. Trescases
1978, Geochimica et Cosmochimica Acta (42) 144-145
Geochemical evidence for modern low-temperature serpentinization has been found in three new localities. Apparently the low-temperature reactions are a common mode of formation of the lizardite-chrysotile and brucite assemblage. Possibly the 18O content of serpentine formed at low temperatures is in part inherited from the pyroxene and olivine. ?? 1978....
Heat flow in the Basin and Range province and thermal effects of tectonic extension
A.H. Lachenbruch
1978, Pure and Applied Geophysics PAGEOPH (117) 34-50
In regions of tectonic extension, vertical convective transport of heat in the lithosphere is inevitable. The resulting departure of lithosphere temperature and thickness from conduction-model estimates depends upon the mechanical mode of extension and upon how rapidly extension is (and has been) taking place. Present knowledge of these processes is...
Complete Bouguer gravity maps and gravity models of the Date Creek basin and vicinity, Maricopa, Mojave, Yavapai, and Yuma Counties, Arizona
Jeffrey C. Wynn, James K. Otton
1978, Open-File Report 78-362
No abstract available....
Reproduction of chaparral shrubs after fire: A comparison of sprouting and seeding strategies
Jon E. Keeley, Paul H. Zedler
1978, American Midland Naturalist (99) 142-161
The relative ability of sprouting and nonsprouting chaparral shrubs to recover from fire was studied by examining population of congeneric pairs of species in burned and adjacent unburned areas. The pairs of species selected, with the nonsprouting species named first, were Arctostaphylos...
Net energy maintenance requirements of salmonids as measured by direct calorimetry: Effect of body size and environmental temperature
R. R. Smith, G. L. Rumsey, M. L. Scott
1978, Journal of Nutrition (108) 1017-1024
Most studies of metabolic rates and energy requirements in aquatic animals have been conducted using indirect methods wherein heat production estimates were based on O2 consumed and CO2 produced. The purpose of the present study was to determine the feasibility of direct calorimetry as a method for measuring heat production of fish...
Isotopic composition of lead in oceanic basalt and its implication to mantle evolution
M. Tatsumoto
1978, Earth and Planetary Science Letters (38) 63-87
New data are given in this report for (1) Pb isotopic compositions and U, Th, and Pb concentrations of basalts from the island of Hawaii; (2) redetermined Pb isotopic compositions of some abyssal tholeiites; and (3) U, Th, and Pb concentrations...
The use of a paired comparison model in ordering stratigraphic events
Lucy E. Edwards, R.J. Beaver
1978, Journal of the International Association for Mathematical Geology (10) 261-272
Data from lowest and highest occurrence events in several stratigraphic sections are analyzed by means of a paired comparison model with ties. The model produces an estimated relative geochronological ordering of these events. This ordering must be compared with actual observations for revision and interpretation. ...
Chemical composition and distribution of lithium-rich brines in salar de Uyuni and nearby salars in southwestern Bolivia
George E. Ericksen, James D. Vine, Raul Ballon A.
1978, Energy (3) 355-363
Preliminary investigations at Salar de Uyuni and the nearby salars (salt pans) of Coipasa and Empexa in the southern part of the Bolivian Altiplano show the presence of widespread lithium-rich brines. Widely scattered brine samples from Salar de Uyuni, which...
Cobalt and scandium partitioning versus iron content for crystalline phases in ultramafic nodules
W.E. Glassley, D.Z. Piper
1978, Earth and Planetary Science Letters (39) 173-178
Fractionation of Co and Sc between garnets, olivines, and clino- and orthopyroxenes, separated from a suite of Salt Lake Crater ultramafic nodules that equilibrated at the same T and P, is strongly dependent on Fe contents. This observation suggests that petrogenetic equilibrium models of...
The moon: Composition determined by nebular processes
J. W. Morgan, J. Hertogen, E. Anders
1978, The Moon and the Planets (18) 465-478
The bulk composition of the Moon was determined by the conditions in the solar nebula during its formation, and may be quantitatively estimated from the premise that the terrestrial planets were formed by cosmochemical processes similar to those recorded in the chondrites. The calculations are based on the Ganapathy-Anders 7-component...
Transient creep and semibrittle behavior of crystalline rocks
N.L. Carter, S. H. Kirby
1978, Pure and Applied Geophysics PAGEOPH (116) 807-839
We review transient creep and semibrittle behavior of crystalline solids. The results are expected to be pertinent to crystalline rocks undergoing deformation in the depth range 5 to 20 km, corresponding to depths of focus of many major earthquakes. Transient creep data for crystalline rocks at elevated temperatures are analyzed...
Methods for regional assessment of geothermal resources
P. Muffler, R. Cataldi
1978, Geothermics (7) 53-89
A consistent, agreed-upon terminology is prerequisite for geothermal resource assessment. Accordingly, we propose a logical, sequential subdivision of the "geothermal resource base", accepting its definition as all the thermal energy in the earth's crust under a given area, measured from mean annual temperature. That part of the resource base which...
Possible fossil H2O liquid-ice interfaces in the Martian crust
L.A. Soderblom, D. B. Wenner
1978, Icarus (34) 622-637
Throughout the northern equatorial region of Mars, extensive areas have been uniformly stripped, roughly to a constant depth. These terrains vary widely in their relative ages. A model is described here to explain this phenomenon as reflecting the vertical distribution of H2O liquid and ice in the crust. Under present...
Applications of the VLF induction method for studying some volcanic processes of Kilauea volcano, Hawaii
C.J. Zablocki
1978, Journal of Volcanology and Geothermal Research (3) 155-195
The very low-frequency (VLF) induction method has found exceptional utility in studying various volcanic processes of Kilauea volcano, Hawaii because: (1) significant anomalies result exclusively from ionically conductive magma or still-hot intrusions (> 800??C) and the attendant electrolytically conductive hot groundwater; (2) basalt flows forming the bulk of Kilauea have...
Geodimeter measurements and the Southern California uplift
W.H. Prescott, J.C. Savage
1978, Earthquake Information Bulletin (USGS) (10) 131-135
Modern surveying instruments, such as geodimeters, are capable of measuring distances in the range of 1 to 30 kilometers with remarkable precision. Indeed, the present limitation upon the precision of measurement is not the resolution of the instruments themselves but rather the uncertainty introduced by variations in the velocity of...
Mate preference in wild and domesticated (game-farm) mallards (Anas platyrhynchos): I. Initial preference
K.M. Cheng, R.N. Shoffner, R.E. Phillips, F.B. Lee
1978, Animal Behaviour (26) 996-1003
Wild and game-farm mallards (Anas platyrhynchos) raised in pure strain and mixed groups were tested for initial mate preference in a choice test. Female mallards showed no significant preference but males of either strain raised with females of their own strain significantly preferred female models of their own strain during...
An automated procedure for the simultaneous determination of specific conductance and pH in natural water samples
D. E. Eradmann, Howard E. Taylor
1978, Analytica Chimica Acta (99) 269-274
An automated, continuous-flow system is utilized to determine specific conductance and pH simultaneously in natural waters. A direct electrometric procedure is used to determine values in the range pH 4–9. The specific conductance measurements are made with an electronically modified, commercially available conductivity meter interfaced to a separate module containing...
The architecture of the porphyry-metal system as a prospecting stratagem in the Southern Rocky Mountains
George J. Neuerburg
1978, Open-File Report 78-130
A model of the porphyry-metal system characteristic of the consanguineous Cretaceous and Tertiary igneous rocks and associated ores of the southern Rocky Mountains is constructed from the bits and pieces exposed in the Colorado mineral belt and the San Juan volcanic field. Hydrothermally altered rocks in a part of the...
Silicate liquid immiscibility in magmas and in the system K2O-FeO-AI2O3-SiO2: An example of serendipity
E. Roedder
1978, Geochimica et Cosmochimica Acta (42) 1597-1617
The concept of silicate liquid immiscibility was invoked early in the history of petrology to explain certain pairs of compositionally divergent rocks, but. as a result of papers by Greig (Am. J. Sci.13, 1–44, 133–154) and Bowen (The Evolution of the Igneous Rocks), it fell into disfavor for many years....
Field and modeling studies of San Francisco Bay
T. J. Conomos, F.H. Nichols, R. T. Cheng, D. H. Peterson
1978, Conference Paper