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Page 5822, results 145526 - 145550

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Publication Extents

Not all publications have extents, not all extents are completely accurate
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...
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...
Blueschist-facies metamorphism related to regional thrust faulting
M.C. Blake Jr., W. P. Irwin, R. G. Coleman
1969, Tectonophysics (8) 237-246
Rocks of the blueschist (glaucophane schist) facies occur throughout the world in narrow tectonic belts associated with ultramafic rocks. In the Coast Range province of California, blueschist rocks are devloped in the eugeosynclinal Franciscan Formation of Late Mesozoic age. The blueschist rocks form a narrow belt for more than 800...
John Wesley Powell: Pioneer statesman of federal science: Chapter A in The Colorado River region and John Wesley Powell (Professional Paper 669)
Mary C. Rabbitt
1969, Professional Paper 669-A
In the middle decades of the 19th century, American science matured rather rapidly. The general scholar with an interest in natural history gave place to the specialist in a particular science, and the various sciences themselves became distinct from each other and from the general body of knowledge. The geological...
Seasonal fluctuations of Lake Michigan diatoms
Ruth E. Holland
1969, Limnology and Oceanography (14) 423-436
Diatoms were collected in four areas of Lake Michigan and in southern Green Bay from April to early November 1965. The flora of the lake was characterized by Fragilaria crotonensis, Tabellaria flocculosa, Melosira islandica, Cyclotella 'glomerata-stelligera,' Cyclotella michiganiana, Asterionella formosa, and Stephanodiscus tenuis. Stephanodiscus niagarae always dominated the diatom biomass...
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....
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...
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...
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...
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...
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...
Pyrolysis of humic and fulvic acids
R.L. Wershaw, G.E. Bohner Jr.
1969, Geochimica et Cosmochimica Acta (33) 757-762
Pyrolysis of humic and fulvic acids isolated from a North Carolina soil yields a variety of aromatic, heterocyclic and straight chain organ compounds. The pyrolysis products identified by gas chromatography and mass spectrometry indicate that humic and fulvic acids have aromatic and polysaccharide...
Interstitial brines in playa sediments
B.F. Jones, A. S. Van Denburgh, A.H. Truesdell, S.L. Rettig
1969, Chemical Geology (4) 253-262
Study of several closed drainages in the Great Basin has shown that the interstitial solutions of shallow, fine-grained playa deposits store a large quantity of dissolved solids and are often more concentrated than associated lakes and ponds, except in peripheral zones of stream or ground-water inflow. These interstitial fluids,...