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An aeromagnetic survey extending from the Gulf of Maine to the tip of Florida was conducted by the U. S. Naval Oceanographic Office between 1964 and 1966. Flight traverses were flown in a northwesterly direction at right angles to the geologic grain. The flight lines were approximately 800 km long and had an 8-km...

No abstract available....

No abstract available....

The K-Ar age of the basal basalt flow at the bottom of the "Lower Canyon group" of lavas near Toroweap fault is 1.16 ± 0.18 standard deviation (sd) m.y. This represents a minimum age of Grand Canyon, for at the time the lava formed, the canyon was essentially as deep as it is today. Since that time the Colorado River has cut through...

A northerly-trending group of quartz diorite stocks that cut Cretaceous, Eocene, 01igocene(?) and Pleistocene( ?) sedimentary rocks near Saindak, West Pakistan, contain oxidized disseminated copper minerals which may occur in commercial concentrations at depth. The stocks are enclosed by an aureole of albite-epidote hornfels about 4 miles wide that locally is cut by veins...

This report is an areal study of a portion of the south coast of Puerto Rico. It follows similar studies of the Guanica, Guayanilla-Yauco, Tallaboa Valley, and Ponce areas to the west and the Jobos area to the east. It basically is an inventory of the water resources during one...

No abstract available....

No abstract available....

No abstract available. ...

It is well known that the Boulder batholith region experienced intensive plutonism, volcanism, and tectonism that all began in Late Cretaceous time, after at least 700 m.y. of structural and igneous inactivity except for sporadic epeirogeny. Recent stratigraphic, structural, paleontologic, arid, especially, radiometric evidence makes it possible to date these...

Water-supply problems in southwest Florida are largely related to the quality, or deterioration in the quality of the water, rather than to the quantity of water available. When we consider that the abundant supply of water visible at the surface is only a fraction of the quantity stored in the...

A seismic-reflection survey was carried out near Denver, Colorado, for the U. S. Geological Survey, to determine if structures exist in the 12,000-ft sedimentary section or in the Precambrian basement that might explain the recent earthquake activity. No major faults were revealed in the sedimentary section. Reflections from a steeply dipping horizon believed to be in the basement complex may be indicative of faulting; however, the magnitude cannot...

The length, age and sex compositions of dead and dying alewives collected in June 1967 at six locations in southern, central, and northern Lake Michigan are compared with those of fish taken in experimental trawls at five locations in April and June 1967. Behavior at the time of death, condition...

Abstract has not been submitted...

Abstract has not been submitted...

Basic water data on the lower Santiam River basin is preliminary to a comprehensive hydrologic study of this productive and intensely irrigated area where expanding population and industry increases the demand for water. Highest yielding wells are in shallow alluvial aquifers near...

Potassium-argon dates for three samples of basaltic scoria from Taylor Valley, on the west side of McMurdo Sound, indicate that the basalt, which antedates and postdates major glaciations, is at least 2.7 million years old....

The integration circuit of the Varian A-60 nuclear magnetic resonance spectrometer is used in conjunction with vapor phase chromatography, to develop a rapid analysis technique for the determination of isomer ratios in technical Systox-Sulfotepp mixtures. The complete analysis requires less than 0.1 g of sample...

In many regions, crystalline rocks are covered by hundreds of meters of unconsolidated and poorly consolidated sediments. Estimates of heat flux within these sediments using standard continental techniques (temperature and conductivity measurements at intervals of 10 to 30 meters) are unreliable, mainly...

Infectious pancreatic necrosis (IPN) is a virulent disease of young trouts and is easily transmitted from infected animals through water and with eggs. At present, the most effective control measure consists of propagation of specific pathogen-free stock. Methods are described for using fish cell cultures to detect IPN virus in...

The North American continental margin beneath the Bering Sea is nearly 1,300 km long and extends from Alaska to eastern Siberia. The margin is a canyon-scarred 3,200–3,400-m high escarpment separating one of the world's largest epicontinental seas (the shallow Bering Sea) and the...

Measurements of stable isotope abundances of the carbonate portion of the sediment in Deep Springs Lake, California, indicate the presence of at least three phases: a magnesian calcite, a primary sedimentary dolomite, and a detrital dolomite. The former two have isotopic compositions consistent with precipitation at isotopic equilibrium from waters...

The electron probe X-ray microanalyzer has been used to determine the compositional variability of the groundmass minerals and glass in 10 specimens from a complete 225-foot section of the prehistoric tholeiitic lava lake of Makaopuhi Crater, Hawaii. The order of beginning of crystallization was: (1) chromite, (2) olivine, (3) augite,...

Sodium-aluminum silicate gels are found in surficial deposits as thick as 5 centimeters in the Magadi area of Kenya. Chemical data indicate they...

It is now well known that William Gilbert, in his De Magnete of 1600, first suggested that the earth behaves as a great magnet. By their very nature, however, such explicit statements tend, in retrospect, to be emphasised at the expense of less explicit antecedent ideas and experiments, with the result that,...