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Page 6258, results 156426 - 156450

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Methane in Lake Kivu: New data bearing on its origin
W.G. Deuser, E.T. Degens, G.R. Harvey, M. Rubin
1973, Science (181) 51-54
Lake Kivu, an African rift lake, contains about 50 cubic kilometers of methane (at standard temperature and pressure) in its deep water. Data resulting from two recent expeditions to the lake and a reevaluation of earlier data suggest that most of the methane was formed by bacteria from abiogenetic carbon...
Analysis of radiotracking data using digitized habitat maps
D.S. Gilmer, S.E. Miller, L.M. Cowardin
1973, Journal of Wildlife Management (37) 404-409
A method is described that provides a rapid and accurate analysis of habitat used by radio-equipped animals. The digitizer (basically an X-Y plotter in reverse) converts maps into digital form by describing each habitat unit as a polygon that closely approximates the actual shape of the unit. The coordinates of...
Mercury residues in pintails breeding in North Dakota
Gary L. Krapu, G.A. Swanson, H.K. Nelson
1973, Journal of Wildlife Management (37) 395-399
Livers of 42 pintail hens (Anas acuta) breeding in eastern North Dakota during the spring and early summer of 1969 and 1970 were analyzed for total mercury by the neutron activation technique. Mercury content on a...
Hydraulics of sheetlike solution cavities
Gerald K. Moore
1973, Groundwater (11) 4-11
The sheetlike solution cavities that supply water to most wells in central Tennessee are 100 to 2,500 feet wide and less than 0.2 inch high. These dimensions have a scale similar to those in Hele-Shaw models. Both logical and mathematical evidence indicate laminar ground-water flow, except close to pumping wells....
Thermochemical approximations for sulfosalts
James R. Craig, Paul B. Barton Jr.
1973, Economic Geology (68) 493-506
Most sulfosalts may be regarded as intermediate phases on joins between simple sulfide components (e.g., all lead sulfbismuthinides lie on the PbS-Bi 2 S 3 join). Many of the structures are characterized by subunits whose individual structures are similar to those of the component simple sulfides (e.g., galena-like and stibnite-like layers in the lead...
Solid solutions in the system Cu-Fe-S, part I: The Cu-S and CuFe-S joins
Paul B. Barton Jr.
1973, Economic Geology (68) 455-465
The data of Rau (1967) on the H 2 S/H 2 ratios of gas in equilibrium with high digenite solid solutions permit the calculation of the activity of Cu 2 S as a function of temperature and composition. The activity of Cu 2 S falls to 0.5 when the mole fraction (in the system Cu 2 S-S) drops only to...
Potassium-Argon ages for minerals from the Ross of Mull, Argyllshire, Scotland
R. D. Beckinsale, J. D. Obradovich
1973, Scottish Journal of Geology (9) 147-156
Sixteen K-Ar ages for samples of biotite and amphibole from the Ross of Mull and analytical data for the standards Bern 4M and W1 are presented. Ages determined for biotite and amphibole samples from the Caledonian pluton average 423 ± 4 m.y. and 416 ± 4 m.y. respectively. Field observations...
The bearing of the new Late Cambrian monoplacophoran genus Knightoconus upon the origin of the Cephalopoda
Ellis L. Yochelson, Rousseau H. Flower, Gerald F. Webers
1973, Lethaia (6) 275-309
Knightoconus, a new genus of the Hypseloconidae (Mollusca: Monoplacophora) from rocks of early Franconian age in Antarctica, is multiseptate. The multiple septa are a criticàl feature to be expected in a form ancestral to cephalopods. Fossil cephalopods, however, invariably have a siphuncle as well as septa; some gastropods, some hyolithids,...
Tests of pesticidal synergism with young pheasants and Japanese quail
J.F. Kreitzer, J. W. Spann
1973, Bulletin of Environmental Contamination and Toxicology (9) 250-256
Thirteen pairs of chemicals involving 18 pesticides and two polychlorinated biphenyl preparations were each fed for 5 days to Japanese quail or ring-necked pheasant chicks 7 to 16 days of age. Malathion + EPN, and malathion + trichlorofon were moderately synergistic in tests with both species, whereas joint toxicities of...
Ground water and geology of Baraga County, Michigan
C. J. Doonan, J.R. Byerlay
1973, Water Investigation 11
Most wells In Baraga County obtain water from beds of sand and gravel in morainal and lakebed deposits or from the Jacobsville Sandstone. Yields of wells range from a few to as much as 115 gallons per minute, but most wells probably yield less than 10 gpm. Large areas, where...
Avalanche mode of motion: Implications from lunar examples
K. A. Howard
1973, Science (180) 1052-1055
A large avalanche (21 square kilometers) at the Apollo 17 landing site moved out several kilometers over flat ground beyond its source slope. If not triggered by impacts, then it was as "efficient" as terrestrial avalanches attributed to air-cushion sliding. Evidently lunar avalanches are able to flow...
Interpretation of a high-grade Precambrian terrane in northern Idaho
Sandra H. B. Clark
1973, Geological Society of America Bulletin (84) 1999-2004
A terrane of high-grade metamorphic rocks in northern Idaho and northeastern Washington is almost completely surrounded by low-grade rocks of the Precambrian Belt Supergroup. The high-grade terrane includes both Belt and pre-Belt rocks. Four events of folding and metamorphism occurred in the high-grade terrane. The first three events may have...
Radiometric ages of intrusive rocks in the Little Belt Mountains, Montana
Richard F. Marvin, Irving J. Witkind, William R. Keefer, Harald H. Mehnert
1973, Geological Society of America Bulletin (84) 1977-1986
Radiometric ages indicate that most, if not all, of the major intrusions in the Little Belt Mountains, central Montana, were emplaced during the Eocene epoch, between 48 and 54 m.y. ago. In the Hughesville area, igneous activity continued, or was episodic until 42 m.y. ago. As a result of the...
Origin of andesitic and granitic magmas in the northern Sierra Nevada, California
Anna Hietanen
1973, Geological Society of America Bulletin (84) 2111-2118
The early magmas of the northern Sierra Nevada, calc-alkaline andesite of island-arc type and its derivatives, all low in potassium, were generated during the Devonian(?) period, possibly along an eastward-dipping sub-duction zone. These magmas could have been derived from mantle peridotite of the continental plate by introduction of water from...
Petrogenesis of the Superstition-Superior volcanic area as inferred from strontium- and oxygen-isotope studies
John S. Stuckless, James R. O’Neil
1973, Geological Society of America Bulletin (84) 1987-1997
Apparent initial Sr87/Sr86 ratios of five ash-flow tuffs (0.7063 to 0.7139) and several mafic to silicic lavas (0.7055 to 0.7131) indicate that the magmas were derived below the base of the Precambrian granitic crust (0.7231 to 1.0906). Liquidus compositions in the system Q-Or-Ab-H2O and oxygen-isotope geother-mometry suggest that the silicic magmas...
Organochlorine pesticides and polychlorinated biphenyls in black duck eggs from the United States and Canada--1971
J. R. Longcore, B.M. Mulhern
1973, Pesticides Monitoring Journal (7) 62-66
Black duck (Anas rubripes) eggs were collected in 1971 from the Northeastern United States and Canada. All 61 eggs analyzed contained DDE residues; the mean DDE residues for States and Provinces ranged from 0.09 to 5.94 ppm on a wet-weight basis, with.mean concentrations exceeding 1.0 ppm in eggs from Maine,...
Phase relations of basalts in their melting range at PH2O = 5 kb as a function of oxygen fugacity: Part I. Mafic phases
Rosalind Tuthill Helz
1973, Journal of Petrology (14) 249-302
The phase relations of three basalts, the Picture Gorge tholeiite, the 1921 Kilauea olivine tholeiite, and the 1801 Hualalai alkali basalt, were studied at 5 kb water pressure, 680–1000°C, at the oxygen fugacities of the quartz-fayalite-magnetite (QFM) and hematite-magnetite (HM) buffers.In the range 680–850 °C, the crystalline assemblage...
Mapping of the 1973 Mississippi River floods from the Earth Resources Technology Satellite (ERTS)
Morris Deutsch, F. H. Ruggles, Philip Guss, Edward Yost
1973, Conference Paper, Remote sensing and water resources management
On March 31, and May 4 and 5, 1973, the first Earth Resources Technology Satellite (ERTS-1) obtained multispectral scanner imagery over the Mississippi River below St. Louis, Missouri. The river was in flood, and the ERTS data provided the first opportunity for regional synoptic mapping of the extent of flooding...
Referees and the publications crisis
Frank T. Manheim
1973, Eos, Earth and Space Science News (54) 532-537
Routine refereeing by peers of manuscripts submitted to scholarly journals is a logical and effective device that can obviate ‘crankiness, irrelevance and gross incompetence’ [Ziman, 1970a] on the one hand and minimize editorial arbitrariness on the other. As reviewed by Zuckerman and Merton [1971], the device has historical roots that extend back...
Fordilla troyensis Barrande: The oldest known pelecypod
J. Pojeta Jr., B. Runnegar, J. Kriz
1973, Science (180) 866-868
Specimens of the small bivalved animal Fordilla troyensis Barrande from New York State show that this fossil is the oldest known pelecypod mollusk and not a conchostracan arthropod. This finding extends the range of the class Pelecypoda backward in time from the Early Ordovician (about 495 million years ago)...
Lonar Lake, India: An impact crater in basalt
K. Fredriksson, A. Dube, D.J. Milton, M.S. Balasundaram
1973, Science (180) 862-864
Discovery of shock-metamorphosed material establishes the impact origin of Lonar Crater. Coarse breccia with shatter coning and microbreccia with moderately shocked fragments containing maskelynite were found in drill holes through the crater floor. Trenches on the rim yield strongly shocked fragments in which plagioclase has melted and vesiculated, and bombs...
Obsidian hydration dates glacial loading?
I. Friedman, K. L. Pierce, J. D. Obradovich, W.D. Long
1973, Science (180) 733-734
Three different groups of hydration rinds have been measured on thin sections of obsidian from Obsidian Cliff, Yellowstone National Park, Wyoming . The average thickness of the thickest (oldest) group of hydration rinds is 16.3 micrometers and can be related to the original emplacement of the flow 176,000 years ago...