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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....

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...

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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...

Recent Soviet and American studies cast new light on the history of the Bering land bridge....

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...

No abstract available....

Aconcagua Province is herein divided into three major structural provinces which, for the sake of simplicity, are named the Coastal Cordillera, Central Valley graben, and Andean Cordillera structural provinces to correspond to the three geomorphic provinces recognized farther south. The coastal structural province includes the Coastal Cordillera which is underlain mainly by layered sedimentary and effusive rocks that strike north and dip...

The Bays Mountain synclinorium is in the Valley and Ridge province in northeast Tennessee, southwest of Kingsport and west of Greeneville. The more clastic part of the Bays formation lies in the east section of the synclinorium. The thickness of the Bays decreases from about 870 feet on the east to about 600 feet on the west. Presumably, the red beds and...