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Page 6538, results 163426 - 163450

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Publication Extents

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Paleomagnetism and the compositions of highly-oxidised iron-titanium oxides in basalts
P.J. Smith
1968, Physics of the Earth and Planetary Interiors (1) 88-92
As a preliminary step towards determination of the source of the natural remanence in highly-oxidised basalt lava flows, electron probe microanalysis has been carried out on the two main phases in each of two types of highly-oxidised iron-titanium oxide. The discovery of the source of NRM in these basalts is...
Mineralogy as a function of depth in the prehistoric Makaopuhi tholeiitic lava lake, Hawaii
B.W. Evans, J.G. Moore
1968, Contributions to Mineralogy and Petrology (17) 85-115
The electron probe X-ray microanalyzer has been used to determine the compositional variability of the groundmass minerals and glass in 10 specimens from a complete 225-foot section of the prehistoric tholeiitic lava lake of Makaopuhi Crater, Hawaii. The order of beginning of crystallization was: (1) chromite, (2) olivine, (3) augite,...
Species succession and fishery exploitation in the Great Lakes
Stanford H. Smith
1968, Journal of the Fisheries Research Board of Canada (25) 667-693
The species composition of fish in the Great Lakes has undergone continual change since the earliest records. Some changes were caused by enrichment of the environment, but others primarily by an intensive and selective fishery for certain species. Major changes related to the fishery were less frequent before the late...
Measurement of geothermal flux through poorly consolidated sediments
J.H. Sass, R. J. Munroe, A.H. Lachenbruch
1968, Earth and Planetary Science Letters (4) 293-298
In many regions, crystalline rocks are covered by hundreds of meters of unconsolidated and poorly consolidated sediments. Estimates of heat flux within these sediments using standard continental techniques (temperature and conductivity measurements at intervals of 10 to 30 meters) are unreliable, mainly...
Simultaneous determination of tantalum and hafnium in silicates by neutron activation analysis
L. P. Greenland
1968, Analytica Chimica Acta (42) 365-370
A neutron activation procedure suitable for the routine determination of tantalum and hafnium in silicates is described. The irradiated sample is fused with sodium peroxide and leached, and the insoluble hydroxides are dissolved in dilute hydrofluoric acid-hydrochloric acid. After LaF3 and AgCl scavenges, tantalum and hafnium...
Pre-gilbertian conceptions of terrestrial magnetism
P.J. Smith
1968, Tectonophysics (6) 499-510
It is now well known that William Gilbert, in his De Magnete of 1600, first suggested that the earth behaves as a great magnet. By their very nature, however, such explicit statements tend, in retrospect, to be emphasised at the expense of less explicit antecedent ideas and experiments, with the result that,...
Isotope studies of dolomite formation under sedimentary conditions
R.N. Clayton, B.F. Jones
1968, Geochimica et Cosmochimica Acta (32)
Measurements of stable isotope abundances of the carbonate portion of the sediment in Deep Springs Lake, California, indicate the presence of at least three phases: a magnesian calcite, a primary sedimentary dolomite, and a detrital dolomite. The former two have isotopic compositions consistent with precipitation at isotopic equilibrium from waters...
Geologic history of the continental margin of North America in the Bering Sea
D.W. Scholl, E. C. Buffington, D.M. Hopkins
1968, Marine Geology (6) 297-330
The North American continental margin beneath the Bering Sea is nearly 1,300 km long and extends from Alaska to eastern Siberia. The margin is a canyon-scarred 3,200–3,400-m high escarpment separating one of the world's largest epicontinental seas (the shallow Bering Sea) and the...
Nuclear magnetic resonance studies of the phosphorus(v) pesticides: A rapid determination of the isomer ratio of systox
H. Babad, T.N. Taylor, M. C. Goldberg
1968, Analytica Chimica Acta (40) 387-392
The integration circuit of the Varian A-60 nuclear magnetic resonance spectrometer is used in conjunction with vapor phase chromatography, to develop a rapid analysis technique for the determination of isomer ratios in technical Systox-Sulfotepp mixtures. The complete analysis requires less than 0.1 g of sample...
Production of sea lamprey larvae from nests in two Lake Superior streams
Patrick J. Manion
1968, Transactions of the American Fisheries Society (97) 484-486
The life history of the landlocked sea lamprey, Petromyzon marinus, has been described by several authors, the two most recent of which are Applegate and Wigley. The only information on the production of larvae from nests of the sea lamprey was reported by Applegate, who counted the larvae from three...
Annulus formation on scales of four species of coregonids reared under artificial conditions
Walter J. Hogman
1968, Journal of the Fisheries Research Board of Canada (25) 2111-2122
Scales from known-age coregonids reared in the laboratory were examined to determine when annuli formed and to learn possible factors of their formation. Scales were taken monthly from marked fish for periods up to 21 months. Scales were also examined from fish that died and from preserved specimens of young-of-the-year...
Water quality of streams tributary to Lakes Superior and Michigan
Jerome W. Zimmerman
1968, Special Scientific Report - Fisheries 559
Water quality of streams tributary to Lakes Superior and Michigan was analyzed for 142 stations on 99 streams tributary to Lake Superior and 83 stations on 56 streams tributary to Lake Michigan during 1962-65. Concentrations of aluminum, copper, and iron were not affected greatly by flow or season. Magnesium, calcium,...
Reward banding to determine reporting rate of recovered mourning dove bands
R. E. Tomlinson
1968, Journal of Wildlife Management (32) 6-11
Reward bands placed on the other leg of certain regularly banded immature mourning doves (Zenaidura macroura) were used to develop information on reporting rates of recovered dove bands. Reports from 15 widely separated sections of the United States showed considerable variation in recovery rate of doves both with and without...
A surface tow net for collection of parasitic-phase sea lampreys
Frederick H. Dahl
1968, Progressive Fish-Culturist (30) 183-184
A STUDY OF MIGRATORY BEHAVIOR of parasitic sea lampreys (Petromyzon marinus) in the Great Lakes required a means of capturing lampreys for tagging and releasing in St. Marys River, Lake Huron. Smith and Elliott (1953) fished specially made gill and trap nets for sea lampreys, but stationary nets could not...
Hydrologic and climatologic data, 1967, Salt Lake County, Utah
A. G. Hely, Reed W. Mower, C. A. Horr
1968, Utah Basic-Data Release 15
An investigation of the water resources of Salt Lake County, Utah, was undertaken by the Water Resources Division of the U.S. Geological Survey in July 1963. This investigation is a cooperative project financed chiefly by equal contributions of the State of Utah and the Federal Government in accordance with an...
Effects of selective fusion on the thermal history of the earth's mantle
W.H.K. Lee
1968, Earth and Planetary Science Letters (4) 270-276
A comparative study on the thermal history of the earth's mantle was made by numerical solutions of the heat equation including and excluding selective fusion of silicates. Selective fusion was approximated by melting in a multicomponent system and redistribution of radioactive elements. Effects of selective fusion on the thermal models...