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The geology, geochemistry, geophysics, and Landsat imagery of the Big Delta quadrangle, 16,335 km 2 in the Yukon-Tanana Upland of east-central Alaska, were investigated, and maps and reports were prepared by an interdisciplinary research team for the purpose of assessing the mineral potential. The quadrangle is dominantly a complex terrane...

Considerable variation in constituent concentrations was shown in urban runoff data for 1975-77 from three metropolitan Denver drainage basins. Constituent concentrations, greatest during initial rainfall runoff, generally peaked midday of snowmelt runoff, corresponding with maximum melting and runoff. Instantaneous loads of constituents were largely a function of discharge. Days since...

Previously unrecognized veins containing lead, zinc, and copper sulfide minerals at Point Delgada, Calif., are associated with late Mesozoic(?) and Tertiary volcanic and sedimentary rocks of the Franciscan assemblage. Sulfide minerals include pyrite, sphalerite, galena, and minor chalcopyrite, and galena-rich samples contain substantial amounts of silver. These minerals occur in...

In 1978, data were collected for identification and quantification of benthic invertebrates, periphyton, and bottom material and their trace-metals concentrations from three sites in Salmon Creek basin, Wash. Metal analyses included arsenic, cadmium, chromium, copper, lead, zinc, selenium, and mercury. Physical data collected included water temperature, dissolved oxygen, pH, discharge,...

In order to assess the contribution to plants and soils of certain elements emitted by phosphate processing, we sampled sagebrush, grasses, and A- and C-horizon soils along upwind and downwind transects at Pocatello and Soda Springs, Idaho. Analyses for 70 elements in plants showed that, statistically, the concentration of 7...

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No abstract available....

The Talkeetna 1° by 3° quadrangle, which consists of about 17,155 km2 in south-central Alaska, was investigated by integrated field and laboratory studies in the disciplines of geology, geochemistry, geophysics, and Landsat data interpretation for the purpose of assessing its mineral resource potential. Past mineral production has been limited to...

Ancient miners, in quest of oxidized copper minerals, gold, silver, and possibly zinc, mined gossans to approximately 20 m depth in an area 1.1 by 0.5 km in extent at Farah Garan. The gossans, derived from sulfides, are ordinarily found at contacts between marble lenses and metavolcanic-metasedimentary rocks, but in...

Five argillitic green beds that alternate with six argillitic purple beds in the upper part of the Spokane Formation of the Belt Supergroup of Proterozoic Y age were sampled by 22 shallow core holes. The holes were drilled on a hexagonal pattern over an area about 50 m wide and...

No abstract available....

Additional x-ray structure studies on low chalcocite generally confirm the previously reported structure but show that either disorder is present or the true space group is not P21/c but Pc, four of the 96 copper atoms in the monoclinic unit cell taking on twofold (linear) coordination. The crystal structure of...

Recent publication of maps at scale 1:1,000,000 of the northeastern equatorial Pacific region showing publicly available information on the nickel plus copper content of manganese nodules has made it possible to outline the prime area between the Clarion and Clipperton fracture zones which has been the focus of several recent...

Partly serpentinized peridotite of early Keweenawan age crops out in two places along a 20-kilometer-long zone of positive aeromagnetic anomalies in northern Marquette County, Michigan. Most of the area is mantled by Pleistocene drift with few bedrock exposures.Petrographic and electron microprobe studies show that the peridotite was originally a plagioclase...

An atomic-absorption spectrometric method is reported for the determination of cobalt, nickel, and copper in a variety of geological materials including iron- and manganese-rich, and calcareous samples. The sample is decomposed with HP-HNO3 and the residue is dissolved in hydrochloric acid. Ammonium fluoride is added to mask iron and 'aluminum. After...

Massive ore-grade zinc, copper and iron sulphide deposits have been found at the axis of the East Pacific Rise. Although their presence on the deep ocean-floor had been predicted there was no supporting observational evidence. The East Pacific Rise deposits represent a modern analogue of Cyprus-type sulphide ores associated with...

Rosascoet al. (1975), reported the first successful application of laser-excited Raman spectroscopy for the identification and nondestructive partial analysis of individual solid, liquid, and gaseous phases in selected fluid inclusions. We report here the results of the application of a new instrument, based on back-scattering, that eliminates many of...

The purpose of this study was to determine the cause of lens cataracts in hatchery trout fed diets containing white fish meal. After preliminary investigations, three experiments were conducted with fry of rainbow trout (Salmo gairdneri) that were fed practical-type diets containing either 40% herring meal (control diet) or 40%...

Applications of 10 therapeutic and two anesthetic agents to healthy smolts of coho salmon (Oncorhynchus kisutch) by conventional methods were followed by two different posttreatment circumstances. In condition I, fish were treated and then transferred directly to 28‰ seawater for 10 days; in condition II, fish were treated and held...

Pervasive secondary biotite-rich mineral assemblages, characteristic of potassic alteration found in the cores of most commercial porphyry copper systems, are associated spatially with a conspicuous color and a geochemical anomaly at La Florida de Nacozari, Sonora. These composite biotite-magnetite assemblages, with or without actinolite, quartz, rutile, sphene, chalcopyrite, and pyrite...

Gold, silver, copper, lead, zinc, pyrite, tin, cobalt, molybdenum, tungsten, barite, and rare-earths have been mined in North Carolina. Gold, with by-product silver, occurs in veins and mineralized shear zones in metamorphic rocks of the Piedmont province and in placers derived from these deposits. Copper occurs with complex sulfide ores...

Landsat Multispectral Scanner (MSS) images of the northwestern part of the Battle Mountain-Eureki, Nevada mineral belt were evaluated for distinguishing hydrothermally altered rocks associated with porphyry copper and disseminated gold deposits. Detection of altered rocks from Landsat is based on the distinctive spectral reflectance of limonite present at coatings on...