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Page 5796, results 144876 - 144900

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Insecticides and the Great Lakes
Robert E. Reinert
1969, Limnos (2) 3-9
Cracks in the perfect image of DDT appeared when traces of the insecticide began to show up in a wide variety of organisms throughout the world. As more and more people investigated this problem, it became increasingly evident that terrestrial and aquatic animals were accumulating comparatively high concentrations of...
Mallard hatching from an egg cracked by freezing
R. J. Greenwood
1969, The Auk (86) 752-754
The eggs of early-nesting waterfowl in North Dakota are frequently exposed to subfreezing temperatures. Mallards (Anas platyrhynchos) and Pintail (Anas acuta), normally the first ducks to arrive in the spring, begin limited early nesting in min-April. Nighttime temperatures during this period frequently drop below freezing, and late spring blizzards are...
Rearing of sea lamprey, Petromyzon marinus, embryos in distilled water
George W. Piavis, John H. Howell
1969, Copeia (1969) 204-205
Most embryological studies of lampreys in the Great Lakes have been conducted with filtered water from Lake Huron. Although this water was entirely satisfactory for the earlier work, the present need for knowledge of the effects of various compounds on embryological development requires that the initial medium be sterile....
Thermochemical study of the system Fe-As-S
P. B. Barton Jr.
1969, Geochimica et Cosmochimica Acta (33) 841-857
The results of Toulmin and Barton (1964) for the Fe-S system have been combined with a series of new measurements on As-bearing assemblages in the 500°–850°C temperature range to derive data on the free energies, enthalpies, and entropies of formation for arsenopyrite, loellingite, orpiment, realgar,...
Alpine-type sensu strictu(ophiolitic) peridotites: Refractory residues from partial melting or igneous sediments? A contribution to the discussion of the paper: "The origin of ultramafic and ultrabasic rocks" by P.J. Wyllie
T. P. Thayer
1969, Tectonophysics (7) 511-516
Although Alpine peridotites and basaltic lavas are widely associated in eugeosynclines and oceanic areas, their genetic ties are obscure. Three major characteristics of olivine-rich Alpine peridotite and dunite—relict cumulus textures, aggregated masses of chromitite, and intimate association with magnesium-rich gabbro — cannot be...
Some triple-filament lead isotope ratio measurements and an absolute growth curve for single-stage leads
J. S. Stacey, M.E. Delevaux, T.J. Ulrych
1969, Earth and Planetary Science Letters (6) 15-25
Triple-filament analyses of three standard lead samples are used to calibrate a mass spectrometer in an absolute sense. The bias we measure is 0.0155 percent per mass unit, and the precision (for 95% confidence limits) is ±0.13% or less for all ratios relative to204Pb. Although its precision is not quite...
Lithium and potassium absorption, dehydroxylation temperature, and structural water content of aluminous smectites
Leonard Gene Schultz
1969, Clays and Clay Minerals (17) 115-149
X-ray analysis of Li+- and K+-saturated samples, differential thermal analysis (DTA), thermal gravimetric analysis (TGA), and chemical analysis of 83 samples enable a distinction to be made between Wyoming, Tatatilla, Otay, Chambers, and non-ideal types of montmorillonite, and between ideal and non-ideal types of beidellite. The Greene-Kelly Li+-test differentiates between...
Extraction of vanadium into isobutyl methyl ketone
Hans J. Crump-Wiesner, W.C. Purdy
1969, Talanta (16) 124-129
Because of its advantages in atomic-absorption spectroscopy, isobutyl methyl ketone was chosen as organic solvent for an extraction study on vanadium. Of eight chelating agents which were evaluated for completeness of extraction, ease of use, working pH range, and freedom from interference, cupferron was judged best.<div...
Geologic structure between the Murray fracture zone and the Transverse Ranges
Roland E. von Huene
1969, Marine Geology (7)
The Murray fracture has been thought to extend ashore into the Transverse Ranges of California, but a geophysical study shows no evidence of structural continuity between these features. Instead, basement morphology typical of the Murray fracture zone ends where its known magnetic and...
The morphology and chronology of a landslide near Dillon Dam, Dillon, Colorado
E.E. Wahlstrom, T. C. Nichols Jr.
1969, Engineering Geology (3) 149-174
Investigations were made of a landslide at the Dillon Dam site, Dillon, Colo., that included detailed laboratory and field analyses of the mineralogy, chemistry, and physical properties of landslide materials and the bedrock formations from which they were derived. These investigations provide an understanding of the relative importance of various...
40Ar/36Ar analyses of historic lava flows
G. B. Dalrymple
1969, Earth and Planetary Science Letters (6) 47-55
The ratio40Ar/36Ar was measured for 26 subaerial historic lava flows. Approximately one-third of the samples had40Ar/36Ar ratios either higher or lower than the atmospheric value of 295.5 at the 95% confidence level. Excess radiogenic40Ar in five flows ranged from about 1 ×...
Cliftonite: A proposed origin, and its bearing on the origin of diamonds in meteorites
R. Brett, G.T. Higgins
1969, Geochimica et Cosmochimica Acta (33)
Cliftonite, a polycrystalline aggregate of graphite with spherulitic structure and cubic morphology, is known in 14 meteorites. Some workers have considered it to be a pseudomorph after diamond, and have used the proposed diamond ancestry as evidence of a meteoritic parent body of at least lunar dimensions. Careful examination of...
A purple-colored 1M mica clay from Silverton, Colorado
Pei-Lin Tien
1969, Clays and Clay Minerals (17) 245-249
A purple-colored clay of 1M mica polymorph in association with lead-zinc ore was collected from an abandoned mine dump near Silverton, Colorado. Electron micrographs show that the crystallites of the clay are less than 2µ in size and have poorly developed hexagonal outlines. Differential thermal and i.r. absorption analyses indicate...
Beach lamination: Nature and origin
H.E. Clifton
1969, Marine Geology (7) 553-559
A distinctive two-fold sedimentation unit characterizes lamination in the upper swash zone of beaches. Within the unit a fine and/or a heavy mineral rich layer at the base grades upward into a coarser and/or a heavy mineral poor layer at the top. This...
Geochemical maps of an area northwest of the Chulitna River, central Alaska Range
C. C. Hawley, Allen L. Clark
1969, Open-File Report 69-123
An area northwest of the Chulitna River in west-central Alaska Range locally shows local anomalous concentrations of gold, silver, arsenic, copper, zinc, and lead in stream-sediment samples. Most stream sediments showing anomalous concentrations of metals can be correlated with either known or newly discovered deposits or occurrences described in Circular...
Environmental impact of oil development in northern Alaska
Luna Bergere Leopold
1969, Report
It is reported that in the spring of 1969 a high official of one of the oil companies was flying over the area of oil development in the vicinity of Prudhoe Bay. He is quoted as saying "If the American people could see what we are doing to their land...