Sr isotopic fractionation in Ca-Al inclusions from the Allende meteorite
P. J. Patchett
1980, Nature (283) 438-441
True relative Sr isotopic compositions, determined by double spiking on Ca-Al inclusions from the Allende meteorite show up to 1.5??? per mass unit mass fractionation relative to the Earth and bulk chondrites. All abnormal inclusions are light-isotope enriched. A lack of isotopically heavy Sr in inclusions would place constraints on...
Small impact craters in the lunar regolith - Their morphologies, relative ages, and rates of formation
H. J. Moore, J. M. Boyce, D.A. Hahn
1980, The Moon and the Planets (23) 231-252
Apparently, there are two types of size-frequency distributions of small lunar craters (???1-100 m across): (1) crater production distributions for which the cumulative frequency of craters is an inverse function of diameter to power near 2.8, and (2) steady-state distributions for which the cumulative frequency of craters is inversely proportional...
A three-dimensional model to predict future oil discoveries in spatially connected multiple plays
J.H. Schuenemeyer, L.J. Drew, W.J. Bawiec
1980, Journal of the International Association for Mathematical Geology (12) 459-472
A discovery-process model that had been devised previously to estimate the size distribution of oil and gas fields remaining to be discovered in a single producing horizon was adapted to a basin containing spatially connected multiple plays and producing horizons. This model used the concept of the area of influence...
Experimental study of free-surface flow instability and bedforms in shallow flows.
I. Karcz, D. Kersey
1980, Sedimentary Geology (27) 263-300
To test erosion and development of bed sculpture in unstable, pulsating shallow flow, 3 series of experiments were performed in a 10-m flume with flows of Reynolds Number up to 103, Froude Number up to 3.0, and slope up to 2%. In the first, the bed was rigid, in the...
(π−1) → (π−1), (π−1) emission spectra of chlorofluorobenzene cations in the gaseous phase and their lifetimes in the (0o) states
John Paul Maier, O. Marthaler, Manijeh Mohraz, R.H. Shiley
1980, Chemical Physics (47) 295-305
The radiative decay of seventeen electronically excited chlorofluorobenzene cations in the gaseous phase has been detected. The reported emission spectra, which have been obtained using low energy electron beam excitation, are assigned to the B(??-1 ??? X(??-1 electronic transitions of these cations on the basis of their Ne(I) photoelectron spectra....
Elastic moduli of rock glasses under pressure to 8 kilobars and geophysical implications
R. Meister, E.C. Robertson, R.W. Werke, R. Raspet
1980, Journal of Geophysical Research Solid Earth (85) 6461-6470
Shear and longitudinal velocities were measured by the ultrasonic phase comparison method as a function of pressure to 8 kbar on synthetic glasses of basalt, andesite, rhyolite, and quartz composition and on natural obsidian. Velocities of most of the glasses decrease anomalously with pressure, but increasingly more-normal behavior occurs with...
Inland (non-tidal) wetland mapping.
W.R. Steward, V. Carter, P. D. Brooks
1980, Photogrammetric Engineering and Remote Sensing (46) 617-628
The US Geological Survey has prepared three experimental wetland maps for the Auburndale, Florida 1:24,000-scale quadrangle. Wetland classes and boundaries were interpreted from quad centered high altitude color infrared and superwide black and white panchromatic photographs onto a black and white orthophoto base map made from a color infrared photograph....
Evaluation of organic matter, subsurface temperature and pressure with regard to gas generation in low-permeability Upper Cretaceous and Lower Tertiary sandstones in Pacific Creek area, Sublette and Sweetwater Counties, Wyoming.
B. E. Law, C. W. Spencer, N. H. Bostick
1980, Mountain Geologist (17) 23-35
The onset of overpressuring occurs at c.3,500 m, near the base of the U. Cretaceous Lance Formation. The development of overpressuring may involve several processes; however, interpretation of the available information indicates that active generation of large amounts of wet gas is one of the more important processes. The present...
Petroleum geology of Kodiak Shelf, Alaska.
Michael A. Fisher
1980, American Association of Petroleum Geologists Bulletin (64) 1140-1157
Organic geochemical data show that Cenozoic rocks on Kodiak Island, in Albatross basin, and under the continental slope generally contain less than 0.5 wt. % organic carbon. Moreover, kerogen from all rocks analyzed is predominantly (60 to 100%) herbaceous; woody and coaly kerogens are present in secondary (20 to 40%)...
A generalized garnet-forming reaction for metaigneous rocks in the Adirondacks
J. M. McLelland, P.R. Whitney
1980, Contributions to Mineralogy and Petrology (72) 111-122
A generalized reaction is presented to account for garnet formation in a variety of Adirondack metaigneous rocks. This reaction, which is the sum of five partial reactions written in aluminum-fixed frames of reference, is given by: 4(y+1+w)Anorthite+4 k(y+1+2 w)Olivine +4(1-k)(y+1+2 w)Fe-oxide+(8(y+1) -4 k(y+1+2 w))Orthopyroxene = 2(y+1)Garnet +2(y+1+2 w)Clinopyroxene+4 wSpinel where...
A model to forecast short-term snowmelt runoff using synoptic observations of streamflow, temperature, and precipitation
Wendell V. Tangborn
1980, Water Resources Research (16) 778-786
Snowmelt runoff is forecast with a statistical model that utilizes daily values of stream discharge, gaged precipitation, and maximum and minimum observations of air temperature. Synoptic observations of these variables are made at existing low- and medium-altitude weather stations, thus eliminating the difficulties and expense of new, high-altitude installations. Four...
Morphology of Lonar Crater, India: Comparisons and implications
R.F. Fudali, D.J. Milton, K. Fredriksson, A. Dube
1980, The Moon and the Planets (23) 493-515
Lonar Crater is a young meteorite impact crater emplaced in Deccan basalt. Data from 5 drillholes, a gravity network, and field mapping are used to reconstruct its original dimensions, delineate the nature of the pre-impact target rocks, and interpret the emplacement mode of the ejecta. Our estimates of the pre-erosion...
Origin of gasoline-range hydrocarbons and their migration by solution in carbon dioxide in Norton basin, Alaska.
Keith A. Kvenvolden, George E. Claypool
1980, American Association of Petroleum Geologists Bulletin (64) 1078-1086
Carbon dioxide from a submarine seep in Norton Sound, Alaska, carries a minor component of gas- and gasoline-range hydrocarbons. The molecular and isotopic compositions of the hydrocarbon gases and the presence of gasoline-range hydrocarbons indicate that these molecules are derived from thermal alteration of marine and/or nonmarine organic matter buried...
Crustal parameters estimated from P-waves of earthquakes recorded at a small array
J.N. Murdock, J.A. Steppe
1980, Pure and Applied Geophysics PAGEOPH (118) 1179-1190
The P-arrival times of local and regional earthquakes that are outside of a small network of seismometers can be used to interpret crustal parameters beneath the network by employing the time-term technique. Even when the estimate of the refractor velocity is poorly determined, useful estimates of the station time-terms can...
Stable isotope and fluid inclusion studies of carbonate deposits from the Tolfa Mountains mining district (Latium, central Italy)
U. Masi, V. Ferrini, J. R. O’Neil, J. N. Batchelder
1980, Mineralium Deposita (15) 351-359
Carbon and oxygen isotope analyses were made of representative samples of calcite and quartz from the carbonate deposits in the Tolfa Mountains mining district. Measurements were also made of hydrogen isotope compositions, filling temperatures and salinities of fluid inclusions in these minerals. There are three stages of mineralization at Tolfa....
Sedimentary masses and concepts about tectonic processes at underthrust ocean margins
D.W. Scholl, Roland E. von Huene, T.L. Vallier, D. G. Howell
1980, Geology (8) 564-568
Tectonic processes associated with subduction of oceanic crust, but unrelated to the collision of thick crustal masses or microplates, are presumed by many geologists to significantly affect the formation and deformation of large sedimentary bodies at underthrust ocean margins. More geologists are familiar with the concept of subduction accretion, which describes...
Resource estimation from historical data: Mercury, a test case
S.M. Cargill, D. H. Root, E. H. Bailey
1980, Journal of the International Association for Mathematical Geology (12) 489-522
A simple technique based on historical records of tonnage and grade of ore produced provides a means for calculating how much of a mineral product will be available in the future at various average grades. Estimates made on this basis are independent of geologic considerations or changing economic and political...
Geophysical investigations in deep horizontal holes drilled ahead of tunnelling
R. D. Carroll, M.J. Cunningham
1980, International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts (17) 89-107
Deep horizontal drill holes have been used since 1967 by the Defense Nuclear Agency as a primary exploration tool for siting nuclear events in tunnels at the Nevada Test Site. The U.S. Geological Survey had developed geophysical logging techniques for obtaining resistivity and velocity in these holes, and to date...
Extraction and concentration of phenolic compounds from water and sediment
Marvin C. Goldberg, Eugene R. Weiner
1980, Analytica Chimica Acta (115) 373-378
Continuous liquid-liquid extractors are used to concentrate phenols at the ??g l-1 level from water into dichloromethane; this is followed by Kuderna-Danish evaporative concentration and gas chromatography. The procedure requires 5 h for 18 l of sample water. Overall concentration factors around 1000 are obtained. Overall concentration efficiencies vary from...
Pomona Member of the Columbia River Basalt Group: an intracanyon flow in the Columbia River Gorge, Oregon.
J. L. Anderson
1980, Oregon Geology (42) 195-199
The Pomona Member of the Saddle Mountains Basalt (Columbia River Basalt Group) occurs as an intracanyon flow greater than 75m (250ft) thick along the S side of the Columbia River Gorge between Mitchell Point and Shellrock Mountain, Oregon. Best exposures are at Mitchell Point, where this flow caps more than...
New evidence for magmatic intrusion beneath the Rio Grande rift, New Mexico
J.N. Towle
1980, Geological Society of America Bulletin (91) 626-630
An analysis of the geomagnetic variation field across the Rio Grande rift has identified two concentrations of telluric current flow beneath the rift caused by channeling of telluric currents in electrically conductive structures in the crust and upper mantle. A shallow conductor nearly...
The morphology of the Martian surface
M. H. Carr
1980, Space Science Reviews (25) 231-284
Most of the southern hemisphere of Mars is densely cratered and stands 1-3 km above the topographic datum. The northern hemisphere is more sparsely cratered and elevations are generally below the datum. A broad rise, the Tharsis bulge, centered at 14?? S, 101?? W, is 8000 km across and 10...
Stable isotope variations in the Quaternary epithermal calcite-fluorite deposit at Monte delle Fate near Cerveteri (Latium, central Italy)
U. Masi, J. R. O’Neil
1980, Mineralium Deposita (15) 41-45
Carbon, oxygen and hydrogen isotope variations have been measured in samples from the epithermal fluorite vein deposit at Monte delle Fate, Latium. The ranges in ?? 13C and ??18O of calcite are -1.3 to 3.4 and 9.5 to 17.3, respectively. ??D values of water extracted from fluid inclusions are -49...
Measurement of irrigated acreage in Western Kansas from LANDSAT images
K.M. Keene, C.D. Conley
1980, Environmental Geology (3) 107-116
In the past four decades, irrigated acreage in western Kansas has increased rapidly. Optimum utilization of vital groundwater supplies requires implementation of long-term water-management programs. One important variable in such programs is up-to-date information on acreage under irrigation. Conventional ground survey methods of estimating irrigated acreage are too slow to...
Comparison of three techniques for the determination of uranium and thorium in rocks
R. J. Hart, D.L. Reid, J. S. Stuckless, H.J. Welke
1980, Chemical Geology (29) 345-350
U and Th concentrations have been determined in a series of selected whole-rock samples, using three different techniques: neutron activation analysis (INAA), X-ray fluorescence spectrometry (XRF) and isotope dilution mass spectrometry (ID). The INAA technique yields U and Th data that are comparable with those obtained by ID over the...
