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Potassium-argon ages of biotite and hornblende from specimens of 17 granitic plutons in the central Sierra Nevada and the western Inyo Mountains, California, range from 69 to 183 m. y. The Mount Givens, Lamarck. and Round Valley Peak Granodiorites and related younger and more felsic...

Duplicate potassium-argon age determinations on each of three samples from widely separated localities indicate that the age of the Bishop Tuff, California, is about 0.7 million years. Two of the samples are from the basal ash fall that preceded the ash flow eruptions; one of...

The sediments of a late glacial sag pond in Huerfano Park, south-central Colorado, have yielded a varied biota consisting of vertebrates, terrestrial and fresh-water mollusks, sponges, and pollen. Wood from the sediments has a radiocarbon age of 9600 ± 200 years. The vertebrate fauna contains the tooth of a prairie...

One to three whole-rock samples from each of more than a dozen discrete plutonic intrusions in the east-central Sierra Nevada batholith have been analyzed for Sr87/Sr86 and Rb/Sr ratios to obtain information on initial Sr87 abundances.The initial Sr87/Sr86 ratios in the rock magmas forming this province appear to have been in the range...

No abstract available....

A study of the effects of field applications of heptachlor on bobwhite quail (Colinus uirginianus) and other animals was conducted on three similar areas, two in Decatur County, Georgia, and one in Escambia County, Alabama, from February, 1958, to March, 1962. Heptachlor in granules was applied by aircraft on the...

A Yashica Sequelle camera was modified and equipped with a timing device so that it would take pictures automatically at 15-minute intervals. Several of these cameras were used to photograph randomly selected quadrats located in different marsh habitats. The number of birds photographed in the different areas was used as...

Tholeiitic basalts (oceanic tholeiites) that form most of the deeply submerged volcanic features in the oceans are characterized by extremely low amounts of Ba, K, P, Pb, Sr, Th, U, and Zr as well as Fe2O3/FeO < 0.2 and Na/K > 10 in unaltered samples. Oceanic tholeiites also have rare earth abundance-distribution patterns and ratios...

Drill‐stem tests provide the petroleum industry information on three critical properties of subsurface formations —pressure head, permeability, and water chemistry –that the ground‐water hydrologist also seeks in making pumping tests of water wells. As it is increasingly necessary to study the hydraulic and geochemical properties of deep‐lying rocks in order to understand the behavior of ground water,...

Shallow aquifers, commonly the most important sources of ground water, are also those most susceptible to contamination. The mode of entry of contaminants to shallow aquifers is (1) directly, via wells or secondary openings in consolidated rocks, (2) percolation through the zone of aeration, (3) induced infiltration through the zone of saturation, and (4) interaquifer leakage...

No abstract available. ...

No abstract available....

The uranium, thorium, and potassium content of hydrothermally altered rocks in the vicinity of several copper and copper-lead-zinc deposits in Arizona was determined by chemical analysis. Potassium in the more intensely altered zones is about twice that in unaltered areas. There is no corresponding increase in thorium, so a higher potassium/thorium ratio also results from...

It was demonstrated with artificially processed sulfides that the minimum temperature of equilibration of a pair of electro-conductive minerals can be determined electrochemically. The procedure consists of setting up an electrochemical cell with the mineral electrodes and a suitable electrolyte, changing the temperature of the cell slowly in a furnace, and finding the temperature at which the emf of the cell becomes zero....

Davis cites four areas of low-angle faulting in which he believes that high fluid pressures can have played no important part in the development and movement of the thrust plates, but it seems to us that the concept or some variant of it may help to explain the observed field...

During 1963, 260 paired photographs and large bottom samples were taken on the continental shelf and slope off northeastern United States. The photographs revealed surface characteristics of the sediments and natural attitudes of benthic animals; the samples retrieved specimens for geological and biological examination and identification.Samples are the best source...

Ramifications of contamination are increasingly involved in the majority of ground‐water problems. The volume of usable ground water is shrinking in many places because of dispersion of contaminated water. Consideration of ground‐water contamination as a multitude of independent problems, separately solvable as each problem arises, is outmoded; wise policies, relating water supply to contamination potential, are needed to alleviate and to forestall problems. Methodology of...

No abstract available. ...

No abstract available. ...

Naturally occurring stable or radioactive isotopes may be used in some places to identify the origin of saline water that contaminates some coastal aquifers. In a recent study to determine the origin of saline water in the Ocala Limestone aquifer near Brunswick, Georgia, the following sources were analyzed for C14 and...

No abstract available....

The following summary of the U. S. Geological Survey gravity program in Washington, Idaho, Montana, and Wyoming is one of a series of short papers that outline Geological Survey gravity projects in the western United States. The substance of this summary is a list of references of published papers on U. S. Geological Survey gravity projects in the northwestern states together with an index map (Figure 1) showing the location of the project, the approximate a...

The one atmosphere isobaric phase relations have been determined for the system As-Sb, using a simple experimental arrangement where a low melting temperature alkali halide melt acts as a reaction vessel. The one atmosphere univariant temperature, where a liquid of composition 45.5 mol % As, plus a solid of composition 62 mol...

No abstract available....

The high-grade hematite deposits of Minas Gerais, Brazil, are those averaging more than 66% Fe and less than 1.5% H20+. They occur in the Caue Itabirite, a metamorphosed oxide-facies iron formation of Pre-cambrian age. This formation was intricately folded during an orogeny that metamorphosed pelitic rocks to the greenschist and almandine-amphi-bole fades, accompanied by the formation...