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The part of the Atlantic Coastal Plain that extends from New Jersey through Virginia was selected as a suitable field model in which to study the relationships between geology, hydrology, and chemical character of ground water. The ground-water flow pattern is the principal hydrologic control on the chemical character of...

Preliminary field tests of an active ultraviolet imaging system have shown that it is possible to produce linages of the terrain from distances as great as 75 feet by means of reflected ultraviolet light at wavelengths longer than 3300 A. Minerals that luminesce when exposed to ultraviolet energy have been...

For many years the structure of the Jura Mountains was interpreted as a décollement whose origin was related to the Alps; in recent years, however, this mode of origin has been questioned. Most of the alternative explanations recognize a décollement to some extent, but attribute it to movement of the...

Downward continuation of the field in the neighborhood of a singularity of a magnetic anomaly is used to render the anomaly more two‐dimensional, to make the bottom of the causal body more remote, and to obtain an auxiliary function, φ (O, z), by means of which the anomaly may be...

During a long-continued study of the lacustrine beds of the Eocene Green River Formation, I have tried to interpret past events from observation of present-day processes. After a search of some 40 years, four lakes have been found that are producing a kind of organic ooze judged to be a...

A study of 23,000 miles of total intensity aeromagnetic profiles in the central Arctic has been made by the U. S. Geological Survey and the U. S. Coast and Geodetic Survey. The profiles were flown at 20,000 feet above sea level and cover approximately 1,350,000 square miles of the Arctic Ocean between the North Pole...

Radiometric ages have been measured on rocks of a crystalline terrane that includes ancient gneisses and migmatites, two granitic batholiths (St. Kevin Granite and granite of Cross Creek), and various minor intrusive rocks. A whole-rock Rb-Sr isochron age on the St. Kevin Granite establishes it as 1390 ± 60 m.y. old. Mineral ages on the St. Kevin and numerous other rocks are either about the same as the St. Kevin whole-rock age...

The States of Nebraska and Kansas are negotiating a compact for apportionment of the waters of the Big and Little Blue Rivers. So that the negotiating officials could allocate the water equitably, the amount of streamflow depletion caused by ground‐water withdrawals upgradient from the State line needed to be determined. At the request of the Nebraska officials, the U. S. Geological Survey...

The tidal efficiencies of wells tapping the principal artesian aquifer in Glynn County, Georgia decrease with distance from the influencing tidal body and also decrease with well depth. Although the magnitude of water‐level fluctuation of these wells is largely dependent upon the distance to a large tidal body, the time of a high or a low water level in the wells is...

The digital computer is used on a routine basis in the ground-water program in Kansas for tasks ranging from the listing of water-quality data in tabular and publishable form to statistically and graphically analyzing a mass of data.In the past year a number of computer programs in FORTRAN IV have...

No abstract available. ...

Compared with the stratified deposits of iron minerals, those of manganese minerals have received little attention until recent years. Before 1930, students of the stratified deposits of manganese minerals have generally concluded that the contained manganese was derived from the decomposition of the rocks that formed the borders of the basins. Only in a few places have geologists recognized that if these...

A moderately violent phreatomagmatic explosive eruption of Taal Volcano, Philippines, occurred from 28 to 30 September, 1965. The main phreatic explosions, which were preceded by ejection of basaltic spatter, opened a new crater 1.5 km long and 0.3 km wide on the southwest side of Volcano Island in Lake Taal....

Moderate supplies of potable ground water are believed to be available in the Roadtown and Paraquita Bay areas, and small, possibly brackish supplies in the Long Look and West End areas of Tortola. Two water bearing units of the same hydrologic system have the potential of yielding water to wells:...

A warm interval that began at least 10,000 years ago and lasted until at least 8300 years ago is recorded in the coastal tundra covered area of northwestern Alaska by the presence of fossil wood of tree size or tree species, fossil beaver-gnawed wood found beyond the modern range of beaver, evidence of ice-wedge melting, buried soils, and soils that...

Theoretical consideration of the charge-transfer mechanism operative in cells with an electrode of a semiconductive binary compound leads to the conclusion that the half-cell potential of such a compound is not only a function of ionic activities in the electrolytic solution, but also a function of the activities of the...

During a three-month trial period, 70 million gallons of industrial wastes were successfully injected at moderate pressures into a deep limestone in the westernmost part of Florida. The movement of these wastes is expected to be predominantly southward toward the natural discharge area which is presumed to be far out...

A feasibility study has been made to operate by remote control an unshielded portable positive-ion accelerator type neutron source to induce activities in the ground or rock by “in situ” neutron irradiation. Selective activation techniques make it possible to detect some thirty or...

The chemical composition, both major and minor constituents, of 60 samples of phosphorite from the Phosphoria Formation was determined. Major constituents of the average phosphorite are, by weight per cent: SiO2, 11·9; Al2O3, 1·7; Fe2O3,1·1; MgO, 0·3; CaO, 44·0; Na2O, 0·6; K2O, 0·5; total H2O, 2·2; H2O−, 0·6; TiO2, 0·1;...

A comparison of 55 older analyses of Australasian tektites with 110 modern precisely monitored analyses suggests that more than half of the older alkali and titania determinations are decidedly inaccurate and misleading. Deviations of the older analyses from the restricted values of the...

Variational principles have been applied to aggregates of randomly oriented pure‐phase polycrystals having tetragonal symmetry. The bounds of the effective elastic moduli obtained in this way show a substantial improvement over the bounds obtained by means of the Voigt and Reuss assumptions. The Hill average is found to be a good approximation in...

The mean velocity of sound has been calculated for 14 crystalline solids by using the best recent values of their single‐crystal elastic stiffness constants. These mean sound velocities have been used to obtain the elastic Debye temperatures θDe for these materials. Models of the three wave velocity surfaces for calcite are illustrated....

Ultimate control of infectious pancreatic necrosis (IPN) in hatcheries depends largely upon learning where the virus occurs. To detect the presence of virus either susceptible fish or susceptible fish cell cultures may be used as test systems. In modern virology, it is generally agreed that cell cultures are more convenient,...