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The San Juan Basin is becoming a major energy resource region. The anticipated increase in strip mining for coal can be expected to alter the geochemical and biogeochemical environment. because such activities destroy the native vegetation communities, rearrange the rock strata, and disrupt natural soil development. This study investigated the...

Bedded deposits of iron-formation are minor components of the thoroughly metamorphosed and deformed Precambrian rocks that make up the core of the Tobacco Root Mountains. The rocks are Archean in age; they predate a major Precambrian orogeny that affected all of southwestern Montana about 2,750 m.y. ago. The principal bed...

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...

The influence of background polychlorinated biphenyl (PCB) residues in rainbow trout (Salmo gairdneri) on the susceptibility of the fish to nine chemicals routinely or occasionally used in fishery operations was evaluated. Rainbow trout fry were divided into three groups: one was exposed to 0.01 ppb and another to 0.1 ppb...

In experiments designed to determine the manner in which copper is partitioned among selected phases that constitute geologic media, we have applied the five-step sequential extraction procedure of Chao and Theobald to the analysis of drill core, soils, and stream sediments of the Rio Vivi and Rio Tanama porphyry copper...

Geochemical studies in the central Brooks Range, Alaska, delineate a regional, structurally controlled mineral belt in east—west-trending metamorphic rocks and adjacent metasedimentary rocks. The mineral belt extends eastward from the Ambler River quadrangle to the Chandalar and Philip Smith quadrangles, Alaska, from 147° to 156°W. longitude, a distance of more...

Fragments of silicified rocks that are associated with deposits of base and precious metals may be transported as cobbles and pebbles in alluvium far downstream from the source outcrop. These rocks commonly exhibit certain characteristics which distinguish them from other detrital siliceous material, and may thus serve as a useful...

A submersible study has been conducted in February–March 1978 at the axis of the East Pacific Rise near 21°N. The expedition CYAMEX, the first submersible program to be conducted on the East Pacific Rise, is part of the French-American-Mexican project RITA (Rivera-Tamayo), a 3-year study devoted to detailed geological and...

Samples of minus-80-mesh (<180 μm) stream sediment, rock containing exposed fracture coatings, and jarosite and chrysocolla were collected from an area surrounding the North Silver Bell porphyry Cu deposit near Tucson, Arizona. The samples were subjected to a series of extractions in a scheme originally designed for use on...

No abstract available. ...

The Patagonia Mountains in southern Arizona contain the deeply buried porphyry copper system at Red Mountain as well as a number of other base- and precious-metal mines and prospects. The range contains complex Basin and Range geology with units ranging in age from Precambrian to Holocene. Rock types present include...

A positive magnetic anomaly extends discontinuously from the south side of the Copper River basin, along the southeast side of Cook Inlet and Shelikof Strait, and southwestward from Kodiak Island to near Sutwik Island. Regionally, this anomaly parallels the Border Ranges fault and...

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...

Thirty-three ospreys (Pandion haliaetus) that were found dead or moribund in the Eastern United States between 1964 and 1973 were necropsied. The brains and carcasses of 26 of these birds were analyzed for organochlorines. The livers of 18 and the kidneys of 7 were analyzed for selected metals. Most adults...

Black duck (Anas rubripes) eggs were collected during 1978 in the Atlantic Flyway. One egg from each of 49 clutches was analyzed for organochlorine compounds and mercury. DDE was detected in 39 eggs, ranging from 0.09 ppm to 3.4 ppm, wet weight. DDE residues were highest in eggs from Delaware,...

The Copper River hydraulic conditions in the vicinity of the Million-Dollar Bridge, Alaska, at the outlet to Miles Lake are described. The water discharge, lake and river bed profiles, bathymetry, velocity, and direction of flow are presented. (Kosco-USGS)...

No abstract available....

The effect of storm runoff on the quality of water in the the Mill Creek drainage basin in west-central New Jersey is described in this report. The study area (23.7 square kilometers) consists of agricultural and undeveloped land and the residential community of Willingboro. From October 1975 to September 1976,...

The strataified-drift aquifer in Farmington, Conn., is capable of yielding large amounts of water to individual wells. About 14 square miles of Farmington is underlain by stratified-drift deposits which, in places, are more than 450 feet thick. The most productive deposits are found in the Farmington River valley, from Unionville...

The Middle and (or) Late Triassic Nikolai Greenstone, part of the allochthonous terrane of Wrangellia, is typically altered and locally metamorphosed to prehnite-pumpellyite facies with chlorite and epidote as the most common secondary minerals. Intrinsic copper content averages 155 ppm, and two types of concentrations of copper in the Nikolai...