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....
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...
Induction of auroral zone electric currents within the Alaska pipeline
W.H. Campbell
1978, Pure and Applied Geophysics PAGEOPH (116) 1143-1173
The Alaskar pipeline is a highly conducting anomaly extending 800 miles (1300 km) from about 62?? to 69?? geomagnetic latitude beneath the most active regions of the ionospheric electrojet current. The spectral behavior of the magnetic field from this current was analyzed using data from standard geomagnetic observatories to establish...
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...
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...
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...
The crystal structure and thermal history of orthopyroxene from lunar anorthosite 15415
H. T. Evans Jr., Huebner J. Stephen, J.A. Konnert
1978, Earth and Planetary Science Letters (37) 476-484
A single crystal of untwinned orthopyroxene from lunar anorthosite sample 15415, with composition (Mg1.14Fe0.80Mn0.02Ca0.04)(Si1.97Al0.03)O6, has a unit cell in space groupPbca witha = 18.310(15)Å,b = 8.904(10)Å,c = 5.214(7)Å, containing 2 formula units. A set of 742 counter-measured intensity data made with MoKα radiation has been used to refine the crystal structure in isotropic thermal mode...
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. ...
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....
Origin of major element chemical trends in DSDP Leg 37 basalts, Mid-Atlantic Ridge
G. R. Byerly, T. L. Wright
1978, Journal of Volcanology and Geothermal Research (3) 229-279
In this paper we summarize the major element chemical variation for basalts from the Deep Sea Drilling Project Leg 37 and relate it to stratigraphic position in each of five drilling sites. Least-squares techniques are successfully used to quantify the nature and extent of alteration in these basalts, and to...
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...
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...
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...
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...
Fecundity of the bloater (Coregonus hoyi) in Lake Michigan
Lee Emery, Edward H. Brown Jr.
1978, Transactions of the American Fisheries Society (107) 785-789
Using ovaries sampled seasonally from Lake Michigan bloaters in 1968-1969, we determined that one complement or modal group of eggs is produced each year and spawned mainly during January, February, and March. Fecundities estimated for 65 fish taken in October ranged from 3,230 eggs in one medium-size bloater (241 mm...
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...
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...
Effects of paved surfaces on recharge to the Floridan aquifer in east-central Florida: A conceptual model
C. H. Tibbals
1978, Water-Resources Investigations Report 78-76
The proportionate amount of surface area that can be paved in Floridan aquifer recharge areas in east-central Florida without reducing the net recharge to the Floridan aquifer is a function of many variables that include rainfall, depth to water table, depth to potentiometric surface of the Floridan, evaporation from paved...
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....
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...
Earthquakes, November-December 1977
W. J. Person
1978, Earthquake Information Bulletin (USGS) (10) 97-99
Two major earthquakes occurred in the last 2 months of the year. A magnitude 7.0 earthquake struck San Juan Province, Argentina, on November 23, causing fatalities and damage. The second major earthquake was a magnitude 7.0 in the Bonin Islands region, an unpopulated area. On December 19, Iran experienced a...
Earthquake history of Wisconsin
C. A. von Hake
1978, Earthquake Information Bulletin (USGS) (10) 100-103
Only one earthquake of intensity V on the Modified Mercalli Intensity Scale (MM) or greater has occurred within Wisconsin during historic times. Some shocks originating in Illinois, Michigan, Missouri, Ohio, and Canada have been felt. ...
Earthquake history of Wyoming
C. A. von Hake
1978, Earthquake Information Bulletin (USGS) (10) 150-154
Forty-five earthquakes of moderate intensity (V or greater) on the Modified Mercalli Intensity Scale (MM) and extent have originated in Wyoming from 1894 to 1976. Many shocks have occurred in Yellowstone National Park, including an intensity VII event in June 1975. the 1959 Hebgen Lake, Mont., earthquake, centered just west...
Field expectations and the determination of wildcat drilling
Emil D. Attanasi, L. J. Drew
1977, Southern Economic Journal (44) 53-67
There is currently some dissatisfaction with macroeconomic approaches to modeling the supply of domestic crude oil. One problem that has been pointed out is that the estimated supply responses of new discoveries brought about by price increases appear to be unrealistically high. Because data frequently used in these models are...