Age of the Morton and Montevideo gneisses and related rocks, southwestern Minnesota
S. S. Goldich, C. E. Hedge, T. W. Stern
1970, Bulletin of the Geological Society of America (81) 3671-3695
Granitic gneisses in the vicinities of Morton and Montevideo in the Minnesota River Valley are dated at 3550 m.y. ago and are the oldest rocks so far found in North America. The gneisses were altered in varying degree by younger events of which two have been dated at 2650 m.y....
Similarities, differences, and some genetic problems of the Wyoming and Colorado plateau types of uranium deposits in sandstone
R. P. Fischer
1970, Economic Geology (65) 778-784
Uranium deposits of the Wyoming roll type and the Colorado Plateau peneconcordant type are the principal domestic resources of uranium. Both types occur in lenticular sandstone beds of continental origin, have a similar suite of elements and minerals, are associated with mildly altered rock, and...
Determining parameters for populations by using structural models
Charles J. Henny, W.S. Overton, H. M. Wight
1970, Journal of Wildlife Management (34) 690-703
A method for calculating parameters necessary to maintain stable populations is described and the management implications of the method are discussed. This method depends upon knowledge of the population mortality rate schedule, the age at which the species reaches maturity, and recruitment rates or age ratios in the population....
Nature and origin of early and late cherts in the Leadville Limestone, Colorado
Norman G. Banks
1970, Bulletin of the Geological Society of America (81) 3033-3048
Two generations of chert have been observed in the Mississippian Leadville Limestone of west-central Colorado: (1) an early chert inferred to have precipitated from hypersaline marine waters of high pH after those waters seeped into carbonate muds prior to final burial and lithification of the carbonate; and (2) a late...
Computer ray tracing through complex geological models for ground motion studies
Nazieh K. Yacoub, James H. Scott, F. A. McKeown
1970, Geophysics (35) 586-602
No abstract available....
Radiogenic heat production of contrasting magma series: Bearing on interpretation of heat flow
Robert I. Tilling, David Gottfried, F. C. W. Dodge
1970, GSA Bulletin (81) 1447-1462
Variation in radiogenic heat production of rocks of diverse magma series (representative of calcic, calc-alkalic, alkali-calcic, and alkalic petrographic provinces on a worldwide basis) is better correlated with some form of magmatic differentiation index, rather than simply with potassium content alone as commonly supposed. The “lime-alkali” (Peacock) index generally gives...
Role of gravity, temperature gradients, and ion exchange media in the formation of fossil brines
P. C. Mangelsdorf Jr., Frank T. Manheim, J. M. Gieskes
1970, American Association of Petroleum Geologists Bulletin (54) 617-626
Calculations show that gravitational settling of ions in an isothermal sediment column could produce increases of equilibrium concentrations in pore waters ranging from 1 percent per 100 m depth for chloride to 4 percent per 100 m depth for strontium.The migration of ions in a thermal gradient (Soret effect) would...
Green River oil shale—concept of origin extended: An interdisciplinary problem being attacked from both ends
W. H. Bradley
1970, GSA Bulletin (81) 985-1000
A much fuller understanding of the Green River oil shale and its organic chemistry will emerge when the geologists, paleontologists, organic chemists, biologists, paleolimnologists, and biogeochemists, who are now working on it, integrate their findings with those of the others.We know from the geology, paleontology, and paleolimnology that the biologic...
Observations of iceberg rafting in Glacier Bay, Alaska, and the identification of ancient ice-rafted deposits
A. Thomas Ovenshine
1970, Bulletin of the Geological Society of America (81) 891-894
Observations of icebergs in a modern glacial marine environment indicate that ancient rocks that received iceberg-rafted material should contain: (1) local concentrations of stones that originated when icebergs overturned, and (2) small pellets of till that were originally sediment filling the spaces between clear ice crystals.The till pellets are especially...
Physical characteristics of the lunar regolith determined from surveyor television observations
Eugene Merle Shoemaker, E. C. Morris
1970, Radio Science (5) 129-155
The new data on the physical characteristics of the lunar surface derived from the Surveyor pictures can be fitted to a simple ballistic model for the origin and development of the lunar regolith. At a given locality, the size-frequency distributions of craters on the lunar surface can...
Variations of major chemical constituents across the central Sierra Nevada batholith
P. C. Bateman, F. C. W. Dodge
1970, Bulletin of the Geological Society of America (81) 409-420
A study of 193 chemical analyses of plutonic rocks from 132 localities in the central Sierra Nevada shows convincingly that K2O decreases systematically westward and suggests that Fe2O3 and TiO2 may also decrease westward and that FeO, MgO, and CaO may increase. The ratio K2O/SiO2 obviously decreases westward across six of eight provisionally...
Nuclear methods applied to uranium geochemistry
J. N. Rosholt
1970, IEEE Transactions on Nuclear Science (17) 173-176
Stable and radioactive daughter products produced from nuclear disintegrations of uranium have proved useful in fundamental studies of the geochemistry of uranium in igneous rock and sedimentary environments and in ore deposits. Information gained from geochemical studies of uranium migration has been used to develop models...
On the theory of evolution of river nets
A. E. Scheidegger
1970, International Association of Scientific Hydrology - Bulletin (15) 109-114
An investigation is made of the growth of river basins based on the two current models of the structure of such basins: the cyclic model and the random-graph model. Based on the assumption that the networks grow allometrically, the structure of the network that evolves has...
Stress of anesthesia with M.S. 222 and Benzocaine in Rainbow Trout (Salmo gairdneri)
Gary Wedemeyer
1970, Journal of the Fisheries Research Board of Canada (27) 909-914
Rainbow trout (Salmo gairdneri) anesthetized with M.S. 222 for periods up to 12 min experience interrenal ascorbate depletion, uremia, and moderate hypercholesterolemia. Anesthesia with neutralized M.S. 222 (pH 7) or benzocaine prevented these changes and significantly reduced the variability in plasma glucose, cholesterol, and cortisol, indicating that the stress of anesthesia...
Lunar regolith at Tranquillity Base
E.M. Shoemaker, M. H. Hait, G.A. Swann, D. L. Schleicher, D.H. Dahlem, G. G. Schaber, R. L. Sutton
1970, Science (167) 452-455
The regolith at Tranquillity Base is a layer of fragmental debris that ranges in thickness from about 3 to 6 meters. The thickness of the regolith and the exposure histories of its constituent fragments can be related, by means of a relatively simple model, to the observed crater distribution....
The determination of low levels of cobalt-60 in environmental waters by liquid scintillation counting
H.C. Claassen
1970, Analytica Chimica Acta (52) 229-235
A method for determination of cobalt-60 in waters at levels greater than 0.5 pCi per sample is presented. A modification of the method may be used to analyze fluvial sediments and soils. After the cobalt has been separated, first as the hydroxide and then as...
Jupiter: His limb darkening and the magnitude of his internal energy source
L.M. Trafton, R.L. Wildey
1970, Science (168) 1214-1215
The most accurate infrared photometric observations (8 to 14 microns) to date of the average limb darkening of Jupiter have been combined with the most refined deduction of jovian model atmospheres in which flux constancy has been closely maintained in the upper regime of radiative equilibrium and a much more...
Petrology of unshocked crystalline rocks and shock effects in lunar rocks and minerals
E. C. T. Chao, O.B. James, J.A. Minkin, J.A. Boreman, E.D. Jackson, C.B. Raleigh
1970, Science (167) 644-647
On the basis of rock modes, textures, and mineralogy, unshocked crystalline rocks are classified into a dominant ilmenite-rich suite (subdivided into intersertal, ophitic, and hornfels types) and a subordinate feldspar-rich suite (subdivided into poikilitic and granular types). Weakly to moderately shocked rocks show high strain-rate deformation and solid-state transformation of...
Photogeologic and thermal infrared reconnaissance surveys of the Los Negritos-Ixtlan de los Hervores geothermal area, Michoacan, Mexico
Valle R. Gomez, J. D. Friedman, S.J. Gawarecki, C.J. Banwell
1970, Geothermics (2)
New techniques, involving interpretation of panchromatic, ektachrome and ektachrome infrared aerographic photogaphs and thermographic infrared imagery recording emission from the earth's surface in middle and far infrared wavelengths (3–5μm and 8–14μm), are being introduced in geothermal investigations in Mexico to identify outstanding structural and geologic features in a rapid and...
Missile impacts as sources of seismic energy on the moon
G.V. Latham, W.G. McDonald, H. J. Moore
1970, Science (168) 242-245
Seismic signals recorded from impacts of missiles at the White Sands Missile Range are radically different from the signal recorded from the Apollo 12 lunar module impact. This implies that lunar structure to depths of at least 10 to 20 kilometers is quite different from the typical structure of the...
Strontium isotopes in Quaternary basalts of southeastern California
Z. E. Peterman, I. S. E. Carmichael, A. L. Smith
1970, Earth and Planetary Science Letters (7) 381-384
Strontium isotopic variations (87Sr/86Sr of 0.7029 to 0.7052) in Quaternary basalts of southeastern California, USA, are not readily explained by assimilation of crustal material similar to that contained as xenoliths in the basalt. Isotopic differences between chrome diopside (0.7016) and olivine...
Phase relations of a simulated lunar basalt as a function of oxygen fugacity, and their bearing on the petrogenesis of the Apollo 11 basalts
R.L. Tuthill, M. Sato
1970, Geochimica et Cosmochimica Acta (34) 1293-1302
A glass of Apollo 11 basalt composition crystallizing at 1 atm at low ƒ02">ƒƒ02 showed the following crystallization sequence; ferropseudobrookite at 1210°C, olivine at 1200°C, ilmenite and plagioclase at 1140°C, clinopyroxene at 1113°C. Ferropseudobrookite and olivine have a reaction relation to the melt. This sequence agrees...
Isotopic composition of strontium in sea water throughout Phanerozoic time
Z. E. Peterman, C. E. Hedge, H. A. Tourtelot
1970, Geochimica et Cosmochimica Acta (34) 105-120
Isotopic analyses of strontium in primary fossil carbonate reveal significant variations in Sr87Sr86">Sr87Sr86 of sea water during the Phanerozoic. The strontium isotopic composition may have been uniform from the Ordovician through the Mississippian, with an average Sr87Sr86">Sr87Sr86 of 0.7078. A subsequent decrease...
Comparison of basic modes for imaging the earth
Alden P. Colvocoresses
1970, Journal of Spacecraft and Rockets (7) 1129-1131
No abstract available....
Irradiation of fish fillets: Relation of vapor phase reactions to storage quality
J. Spinelli, A.M. Dollar, Gary Wedemeyer, E.C. Gallagher
1969, International Journal of Applied Radiation and Isotopes (20) 167-175
Fish fillets irradiated under air, nitrogen, oxygen, or carbon dioxide atmospheres developed rancidlike flavors when they were stored at refrigerated temperatures. Packing and irradiating under vacuum or helium prevented development of off-flavors during storage.Significant quantities of nitrate and oxidizing substances were formed when oxygen, nitrogen, or air were present in...