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The Dickinson area is underlain by the coal-bearing Fort Union Formation (Paleocene). The Fort Union in this area contains nine potentially economic coal beds. Five of these beds are, either all or in part, shallow enough to be economically extracted by conventional strip-mining methods, while the remaining four deeper beds...

Extensive water withdrawal from the Floridan aquifer in the urban Tampa Bay area has induced leakage from the overlying surficial aquifer adversely effecting the water table and lake levels. Artificial recharge could reduce the impact of these effects. Four experiments were conducted to investigate possible recharge alternatives; sinkhole recharge, water-spreading,...

Precambrian sulfide deposits in the Southern Rocky Mountains in Colorado are being studied and re-evaluated according to geologic concepts which were developed in recent years in other parts of the world during successful research regarding economic massive sulfide deposits. These studies, initiated in 1974 in Colorado by the U.S. Geological...

The Hidden Water Creek area in Wyoming was mined from 1944 to 1955 and abandoned. The open pits filled with water and pond-type ecosystems developed. Light was transmitted to greater depths within two control ponds located outside the mine area. The lower light transmittance in the ponds within the mined...

Statewide regression equations are defined for estimating peak discharges of floods having recurrence intervals ranging from 2 to 500 years. Contributing drainage area, main-channel slope and mean annual precipitation are the independent variables required for estimating flood discharges for rural streams. For urban streams the percentage of the basin that...

The Atlanta Regional Commission and the Earth Resources Observation Systems Data Center participated in a demonstration of the use of Landsat digital data to detect land use change in the Atlanta, Ga., area. Temporal overlays combining Landsat band-5 data from October 1972 and 1974 were made by using the General...

A legend is suggested for use with computer-generated thematic maps made from Landsat digital data that designates some of the radiometric characteristics of each thematic map unit as well as the described terrain attributes of each map unit. The relationship between spectral band and radiance for each map unit is...

The Department of Interior's EROS Data Center, managed by the U.S. Geological Survey, was established in 1972, in Sioux Falls, South Dakota, to serve as a principal dissemination facility for Landsat and other remotely Sensed data. Through the middle of 1977, the Center has supplied approximately 1.7 million copies of...

A brief study involving collection and analysis of street sweepings was undertaken to provide the U.S. Army Corps of Engineers with data on physical, chemical, and biological characteristics of dust and dirt accumulating on Portland streets. Most of the analyses selected were based on the pollutant loads predicted by the...

Specific growth rate of Cryptomonas ovata var. palustris Pringsheim was measured in batch culture at 14 light-temperature combinations. Both the maximum growth rate (μm) and optimum light intensity (Iopt) fit an empirical function that increases exponentially with temperature up to an optimum (Topt), then declines rapidly as temperature exceeds Topt. Incorporation of these functions into Steele's growth equation gives a...

The bibliography contains 82 citations of selected publications and technical reports.  The references deal with the application of remote sensing techniques to the collection and analysis of geographic data.  All of the citations were published between January 1968 and July 1977....

After acid decomposition of the sample, selenium hydride was generated by means of sodium borohydride, and the gas was swept through a resistance-heated quartz cell mounted in an atomic absorption spectrometer to determine as little as 5 ng/g selenium in 0.25 g rock sample. One-way analyses of variance of data...

Epithermal beryllium deposits in western Utah have distinctive geological and geochemical associations that provide guides to exploration for new resources of beryllium and associated metals. Beryllium deposits at Spor Mountain and the Honeycomb Hills are uniquely associated with topaz-bearing rhyolite of Late Tertiary age and are restricted to porous water-laid...

Leech parasitism of waterfowl is widespread in North America. Twenty species of ducks, geese, and swans have been infested by leeches, particularly Theromyzon rude and Placobdella ornata. Sites of attachment include the eyes, nasal passages, and body. Information is lacking on the biology and ecology of duck leeches. Their significance...

No abstract available....

No abstract available....

Ash flows around Aniakchak and Fisher calderas in the Aleutian volcanic arc show evidence of having flowed over formidable topographic barriers at distances of tens of kilometres from their source. Ash flows swept down glaciated valleys on the south side of Aniakchak caldera, crossed a broad lowland with an altitude...

Computer enhancement, particularly contrast-stretching, reveals a previously unnoticed east-west structural zone across a Landsat image of the southern Brazilian Precambrian shield. In this zone occur the only known economic or near-economic deposits of gold, tin, and copper. Such deposits are typically localized by small east-west structural elements. Non-economic copper occurrences...

No abstract available....

Ribbon cherts and siliceous tuffs of the North Fork and Rattlesnake Creek terranes of the Klamath Mountains yield Mesozoic radiolarians. Rocks of the North Fork terrane were previously considered to be of Paleozoic age and those of the Rattlesnake Creek to be of Paleozoic and Triassic age, on the basis...

No abstract available....

No abstract available....

Grain size, bedding thickness, dispersion of cross-stratification azimuths, and assemblages of sedimentary structures and trace fossils vary across central Arizona; they form the basis for recognizing six facies (A through F) in the Tapeats Sandstone. Five of these (A through E), present in western central Arizona, are marine deposits containing...

Unusual concentrations of dissolved two- to four-carbon alkanes were observed in the waters in Norton Sound in a localized area approximately 40 kilometers south of Nome, Alaska, in 1976. The hydrocarbons were identified in the near-bottom waters downcurrent for more than 100 kilometers from a sea-floor point source. Preliminary dynamic...