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Field studies have thrown new light on a unique prehistoric encounter of a cosmic body with the earth....

During the past 10 years, personnel of the U. S. Geological Survey have made about 14,000 observations of the Earth's gravity field in California, about 13,000 in Nevada, 3,400 in Oregon, and about 1,000 in the Hawaiian Islands. The total number of stations established in the four states is slightly...

Eclogites are divisible into three groups based on mode of occurrence: Group A, inclusions in kimberlites, basalts, or layers in ultramafic rocks; Group B, bands or lenses within migmatite gneissic terrains; Group C, bands or lenses within alpine-type metamorphic rocks. The compositions range from olivine basalt for Group A to...

No abstract available....

The immune response among fish, from a phylogenetic standpoint, presents a progressive pattern of increasing development. The cyclostomes have been shown to have only feeble immunologic responsiveness. One of their number, the hagfish, appeared to be totally lacking in the ability to actively acquire antibodies.Among the elasmobranchs, the sharks have...

A field trial of Phosphamidon applied by aircraft in Montana against spruce budworm (Choristoneura fumiferana) had immediate adverse effects on birds. A 5,000-acre block of forested land was sprayed at the rate of 1 pound per acre. Some birds, including blue grouse (Dendragapus obscurus), were killed by the insecticide. Bird...

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. ...

Alaska's Good Friday earthquake of 27 March 1964 was accompanied by vertical tectonic deformation over an area of 170,000 to 200,000 square kilometers in south-central Alaska. The deformation included two major northeast-trending zones of uplift and subsidence situated between the Aleutian Trench and the Aleutian Volcanic Arc; together they are...

Radiocarbon ages of basal peats 4500 years old or younger and the thickness of salt-marsh peat in the lagoon east of Wachapreague, Virginia, are nearly the same as those of equivalent samples from New Jersey and Cape Cod. This suggests that these coasts have had similar submergence histories. Data obtained...

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....

Lake Vanda in Victoria Land, Antarctica, is permanently ice-covered and permanently stratified, with warm, salty water near the bottom. Deuterium analyses of lake water from several levels indicate that the lake has a low deuterium content, and that it is stratified with respect to this isotope. This low deuterium content...

Carbon-14 activity was determined from HCO3- in samples of groundwater obtained from the principal artesian aquifer in Florida. From these data the "age" of water obtained from a series of wells, each progressively farther down gradient on the piezometric surface, was established. Relative carbon-14 ages indicated a velocity...

Preliminary aerial photographic studies indicate that the Alaskan earthquake produced some rockfalls but no significant snow and ice avalanches on glaciers. No rapid, short-lived glacier advances (surges) are conclusively associated with this earthquake. Recent evidence fails to support the earthquake-advance theory of Tarr and Martin....