Earthquake swarms and local crustal spreading along major strike-slip faults in California
C.S. Weaver, D.P. Hill
1978, Pure and Applied Geophysics PAGEOPH (117) 51-64
Earthquake swarms in California are often localized to areas within dextral offsets in the linear trend in active fault strands, suggesting a relation between earthquake swarms and local crustal spreading. Local crustal spereading is required by the geometry of dextral offsets when, as in the San Andreas system, faults have...
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...
Determination of dissolved boron in fresh, estuarine, and geothermal waters by d.c. argon-plasma emission spectrometry
J.W. Ball, J. M. Thompson, Everett A. Jenne
1978, Analytica Chimica Acta (98) 67-75
A d.c. argon-plasma emission spectrometer is used to determine dissolved boron in natural (fresh and estuarine) water samples. Concentrations ranged from 0.02 to 250 mg l-1. The emission—concentration function is linear from 0.02 to 1000 mg l-1. Achievement of a relative standard deviation of ⩽ 3% requires frequent restandardization to...
Uranium-lead isotope systematics and apparent ages of zircons and other minerals in precambrian granitic rocks, Granite Mountains, Wyoming
K.R. Ludwig, J. S. Stuckless
1978, Contributions to Mineralogy and Petrology (65) 243-254
Zircon suites from the two main types of granite in the Granite Mountains, Wyoming, yielded concordia-intercept ages of 2,640??20 m.y. for a red, foliated granite (granite of Long Creek Mountain) and 2,595??40 m.y. for the much larger mass of the granite of Lankin Dome. These ages are statistically distinct (40??20...
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...
Identification and significance of accessory minerals from a bituminous coal
R. B. Finkelman, R.W. Stanton
1978, Fuel (57) 763-768
A scanning electron microscope (SEM) has been used to study the in situ accessory minerals in polished blocks and pellets of petrographically analysed samples of the Waynesburg coal (hvb). Individual grains from the low-temperature ash (LTA) of the same coal were also studied. The visual resolution of the SEM permitted the detection...
Stability of fluoride complex with silica and its distribution in natural water systems
C. E. Roberson, R.B. Barnes
1978, Chemical Geology (21) 239-256
Fluoride reacts with silicic acid to form SiF2−6. A fluoride electrode was used to obtain an equilibrium constant of 1030.18 for the reaction:Si(OH)06+ 6F−+4H+=SiF2−6+ 4H2O">Si(OH)06+ 6F−+4H+=SiF2−6+ 4H2O at 25°CAlthough there may be some experimental evidence for...
Formation of lunar basin rings
C. A. Hodges, D.E. Wilhelms
1978, Icarus (34) 294-323
The origin of the multiple concentric rings that characterize lunar impact basins, and the probable depth and diameter of the transient crater have been widely debated. As an alternative to prevailing “megaterrace” hypotheses, we propose that the outer scarps or mountain rings that delineate the topographic rims of basins—the Cordilleran...
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...
Mars, highlands-lowlands: Viking contributions to mariner relative age studies
D. H. Scott
1978, Icarus (34) 479-485
Stratigraphic relations between lowland plains and highlands, two major types of Martian geologic-terrain units, were not directly distinguishable on Mariner-9 images. Morphologic characteristics and crater densities suggested that the lava plains beneath their eolian cover were younger than adjacent highland rocks, which form a plateau bounded in many places by...
Distribution and relations of 4- to 10-km-diameter craters to global geologic units of Mars
C.D. Condit
1978, Icarus (34) 465-478
By correlating the 1:25,000,000 geologic map of Mars of Scott and Carr (1977) with 4- to 10-km-diameter crater density data from Mariner 9 images, the average crater density for 23 of the equatorial geologic-geomorphic units on Mars was computed. The correlation of these two data sets was accomplished by digitizing...
Prediction of capacity factors for aqueous organic solutes adsorbed on a porous acrylic resin
E.M. Thurman, Ronald L. Malcolm, G. R. Aiken
1978, Analytical Chemistry (50) 775-779
The capacity factors of 20 aromatic, allphatic, and allcycllc organic solutes with carboxyl, hydroxyl, amine, and methyl functional groups were determined on Amberlite XAD-8, a porous acrylic resin. The logarithm of the capacity factor, k', correlated inversely with the logarithm of the aqueous molar solubility with significance of less than...
Friction of rocks
J. Byerlee
1978, Pure and Applied Geophysics PAGEOPH (116) 615-626
Experimental results in the published literature show that at low normal stress the shear stress required to slide one rock over another varies widely between experiments. This is because at low stress rock friction is strongly dependent on surface roughness. At high normal stress that effect is diminished and the...
Velocity anomalies: An alternative explanation based on data from laboratory experiments
D.A. Lockner, J.D. Byerlee
1978, Pure and Applied Geophysics PAGEOPH (116) 765-772
Locations and velocities were calculated for microseisms occurring in samples of rock subjected to triaxial loading and injection of pore fluid. This was accomplished by analyzing arrival times of acoustic emission using an automatic first arrival picker. Apparent velocity anomalies were observed prior to both failure of intact samples and...
Interpretation of a Landsat image of an unusual flood phenomenon in Australia
Charles J. Robinove
1978, Remote Sensing of Environment (7) 219-225
A Landsat image of part of the flooded area of Cooper Creek, Queensland, Australia, in February 1974, shows large dark areas within the flooded valley. The dark areas are believed to be wet, but unflooded, areas of dark alluvial soil. These striking features, which have not previously been identified on...
Oxygen and hydrogen isotope compositions of eclogites and associated rocks from the Eastern Sesia zone (Western Alps, Italy)
J. Desmons, J. R. O’Neil
1978, Contributions to Mineralogy and Petrology (67) 79-85
Oxygen and hydrogen isotope analyses have been made of mineral separates from eclogites, glaucophanites and glaucophane schists from the eastern Sesia zone (Italian Western Alps). Regularities in (1) hydrogen isotope compositions, (2) order of 18O enrichment among coexisting minerals, and (3) ?? 18O (quartz-rutile) and ?? 18O (quartz-phengite) imply attainment...
Environmental trade-offs of tunnels vs cut-and-cover subways
M. Walton
1978, Underground Space (3) 61-67
Heavy construction projects in cities entail two kinds of cost - internal cost, which can be defined in terms of payments from one set of parties to another, and external cost, which is the cost borne by the community at large as the result of disutilities entailed in construction and...
A pollution history of Chesapeake Bay
E.D. Goldberg, V. Hodge, M. Koide, J. Griffin, E. Gamble, O.P. Bricker, G. Matisoff, G.R. Holdren Jr., R. Braun
1978, Geochimica et Cosmochimica Acta (42) 1413-1425
Present day anthropogenic fluxes of some heavy metals to central Chesapeake Bay appear to be intermediate to those of the southern California coastal region and those of Narragansett Bay. The natural fluxes, however, are in general higher. On the bases of Pb-210 and Pu-239 + 240 geochronologies and of the...
Empirical model of Skeletonema costatum photosynthetic rate, with applications in the San Francisco Bay estuary
James E. Cloern
1978, Advances in Water Resources (1) 267-274
An empirical model of Skeletonema costatum photosynthetic rate is developed and fit to measurements of photosynthesis selected from the literature. Because the model acknowledges existence of: 1) a light-temperature interaction (by allowing optimum irradiance to vary with temperature), 2) light inhibition, 3) temperature inhibition, and 4) a salinity effect, it accurately estimates...
Analytical multicollimator camera calibration
W.P. Tayman
1978, Photogrammetria (34) 179-197
Calibration with the U.S. Geological survey multicollimator determines the calibrated focal length, the point of symmetry, the radial distortion referred to the point of symmetry, and the asymmetric characteristiecs of the camera lens. For this project, two cameras were calibrated, a Zeiss RMK A 15/23 and a Wild RC 8....
Mars synthetic topographic mapping
S.S.C. Wu
1978, Icarus (33) 417-440
Topographic contour maps of Mars are compiled by the synthesis of data acquired from various scientific experiments of the Mariner 9 mission, including S-band radio-occulation, the ultraviolet spectrometer (UVS), the infrared radiometer (IRR), the infrared interferometer spectrometer (IRIS) and television imagery, as well as Earth-based radar information collected at Goldstone,...
Distribution of rutile in metamorphic rocks and implications for placer deposits
R. Goldsmith, E. R. Force
1978, Mineralium Deposita (13) 329-343
Pelitic units in the eastern Great Smoky Mountains of the North Carolina Blue Ridge contain rutile grains only in kyanite and higher zones. Adjacent non-pelitic rocks do not contain rutile at kyanite grade but commonly contain sphene. Detrital rutile breaks down at metamorphic grades lower than those at which metamorphic...
Radioactive disequilibrium in altered mid-oceanic basalts
M.P. Bacon
1978, Earth and Planetary Science Letters (39) 250-254
A young (<1 m.y.) tholeiitic basalt dredged from the Mid-Atlantic Ridge displays a234U excess and a230Th deficiency that have resulted from the addition of seawater uranium during weathering at seafloor temperatures. Two older samples, though they acquired substantial amounts of uranium...
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...
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...
