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The months were seismically active, although only one major event (7.0-7.9) occurred in an unpopulated Philippine Island. Mexico was struck by a 6.3 quake on June 9 killing at least two people. The most significant earthquake in the United States was in the Mammoth Lakes area of California. -from Author...

Upper Jurassic gray and red-brown shale, sandstone, and coal are the oldest strata penetrated by the Shell 272-1 and 273-1 wells, located approximately 66 mi (106 km) southeast of Atlantic City, New Jersey, in the northwest part of the Baltimore Canyon Trough. The Lower Cretaceous section consists of gray shale...

Garnet-two-mica granites of Jurassic (160 ± 3 m.y.) and Cretaceous (83 ± 1.3 m.y.) ages intrude amphibolite facies metasedimentary rocks of Precambrian age and lower Paleozoic sedimentary rocks in the northern part of the Ruby Mountains, Nevada. High initial 87Sr/86Sr and high values of δ18O for minerals suggest a dominantly sedimentary...

The234U and238U concentration in brine from six Gulf Coast geopressured aquifers has been determined. The results reveal very low uranium concentrations (from 0.003 to 0.03 μg/l) and uranium activity ratios slightly greater than unity (from 1.06 to 1.62). Reducing conditions within the aquifers are responsible for the low uranium concentrations....

In the northern Great Plains, large quantities of biogenic methane are contained at shallow depths in Cretaceous marine mudstones. The Gammon Shale and equivalents of the Milk River Formation in Canada, which comprise most sediments deposited offshore during the Eagle-Telegraph Creek regression, are typical of such gas-bearing rocks. At Little...

Fingerling rainbow trout (Salmo gairdneri) were fed purified diets containing graded levels (0, 3, 6, 12, 18, 24, and 54 mg/kg) of supplemental riboflavin for 20 weeks. The cellular riboflavin supply of the fingerlings was estimated on the basis of the activity of the FAD‐dependent enzyme, erythrocyte glutathione reductase (EGR)....

Historical production statistics are used to predict the quantity of remaining usable resources. The commodities considered are mercury, copper and its byproducts gold and silver, and petroleum; the production and discovery data are for the United States. The results of the study indicate that the cumulative return per unit of...

No abstract available....

The buildup of salmonid populations in Lake Michigan through annual stockings of hatchery-reared fish may become limited by the quantity of forage fish, mainly alewives Alosa pseudoharengus, available for food. As a part of a continuing examination of salmonid predator-prey relations in Lake Michigan, we traced changes in alewife biomass...

To determine how much organic nitrogen is lost from lakes during winter by natural processes, we collected water in fall and winter from six small lakes (area, 5-822 hectares) and separated organic matter dissolved in the water with n-butanol into three fractions--yellow organic acids, a white precipitate, and aqueous (nonextractable)...

The earthquake occurred at 1.25 pm local time and had a surface-wave magnitude of 7.3. The main event was followed by an aftershock 3 hours later with a magnitude of 6.0. The main earthquake epicenter was located 170 km from the capital, Algiers. -from Author...

This report is a digest of information furnished by Federal agencies conducting sedimentation investigations on work in progress or planned, important findings, new methods, new publications, laboratory and other research activities, and other pertinent information. The material has been organized by major drainage regions in the conterminous United States, Alaska,...

No abstract available ...

The study is a geohydrologic reconnaissance of about 170 square miles in the Lake Mead National Recreation Area from Las Vegas Wash to Opal Mountain, Nevada. The study is one of a series that describes the geohydrology of the recreation area and that indentifies areas where water supplies can be...

A wide range of rock types (abyssal tholeiite, Fe-Ti-rich basalt, andesite, and rhyodacite) were dredged from near 95°W and 85°W on the Galapagos spreading center. Computer modeling of major element compositions has shown that these rocks could be derived from common parental magmas by successive degrees of fractional crystallization. However,...

The potentiometric surface of the Wilcox-Carrizo aquifer in central northwestern Louisiana is shown by contours using data collected from 1960 to 1980. The aquifer is not affected by regional water-level declines as no large pumping centers have been developed. Seasonal water-level fluctuations in wells are generally less than 10 feet...

No abstract available....

New map projections to be used for plotting successive satellite groundtracks show these tracks as straight lines. The map may be made conformal along any 2 parallels of latitude between the limits of latitude reached by the groundtrack, or the 'tracking limits'. If these parallels are equidistant from the Equator,...

Both theoretical considerations and available experimental results indicate that magnetic effects of maghemitization are strongly dependent on the grain size of the originally unoxidized titanomagnetite. Maghemitization of single‐domain titanomagnetite results in a decrease in coercivity, an increase in susceptibility, and a large decrease in Q ratio. Maghemitization of multidomain titanomagnetite results in...

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Although few biological data exist on the now extinct native lake trout, Salvelinus namaycush, of Lake Michigan, historical records and interviews with former commercial fishermen strongly suggest that this once widespread resource was composed of a number of discrete spawning populations or stocks. A natural division of the resource into distinct...