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Conference Papers

Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.

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ASSESSMENT OF CHANNEL STABILITY AT BRIDGE SITES.

Assessment of channel stability from field study and the comparison of time-sequential aerial photographs provides information that is needed in site selection, bridge design, and countermeasure placement. Channel instability is indicated by bank erosion, progressive degradation (or aggradation) of the streambed, or natural scour and fill of the streambed. Bank erosion rates are related to stream
Authors
James C. Brice

ASSESSMENT OF HIGH-TEMPERATURE GEOTHERMAL RESOURCES IN HYDROTHERMAL CONVECTION SYSTEMS IN THE UNITED STATES.

The amount of thermal energy in high-temperature geothermal systems (>150 degree C) in the United States has been calculated by estimating the temperature, area, and thickness of each identified system. These data, along with a general model for recoverability of geothermal energy and a calculation that takes account of the conversion of thermal energy to electricity, yield a resource estimate of
Authors
Manuel Nathenson

BROADBAND DIGITAL GEOPHYSICAL TELEMETRY SYSTEM.

A system has been developed to simultaneously sample and transmit digital data from five remote geophysical data receiver stations to a control station that processes, displays, and stores the data. A microprocessor in each remote station receives commands from the control station over a single telemetry channel.
Authors
Robert L. Seeley, Jeffrey J. Daniels

CAUSATIVE FACTORS AND VARIATION OF SEDIMENT YIELDS IN KENTUCKY.

Precipitation, topography, runoff, soils, and land use are the major causative factors of sediment yield in Kentucky. The variability and interaction of these factors directly affects the amount and type of sediment yields. Sediment yield and size data were collected during 1942-45 and 1951-81 throughout the five major physiographic regions of Kentucky and at selected stations on the main stem of
Authors
Clyde J. Sholar

Characterization and geochemistry of Devonian oil shale North Alabama - South Central Tennessee

Based on the physical and chemical data obtained to date, the Devonian oil shale rock of north Alabama and south-central Tennessee appears to offer an attractive potential for future resource development. The shale rock appears to have formed in a restrictive marine environment which provided opportunity for the accumulation of marine organic matter to form sufficient kerogen. The shale contains a
Authors
K.F. Rheams, T.L. Neathery

CHARACTERIZATION OF SECONDARY ALTERATION IN THE COLUMBIA RIVER BASALT BY BACKSCATTERED ELECTRON IMAGING AND ENERGY-DISPERSIVE X-RAY SPECTROSCOPY.

The thick sequences of flood basalts which underlie the Columbia River basin are important aquifiers, providing water for both agricultural and domestic use. Secondary alteration in these rocks occurs primarily as coatings or fillings in fractures and vesicles; alteration is generally believed to have occurred at low temperatures ( less than 100 C) by reaction with meteroic waters. The distributio
Authors
P.P. Hearn, W.C. Steinkampf, Z. A. Brown

Characterization of the oil shale of the New Albany Shale in Indiana

In the 1920's chemical and mineralogic characterization of the New Albany Shale (Mississippian-Devonian) in Indiana showed the dark shale to be rich in organic material and have commercial possibilities. Projects in the 1960's resulted in disparaging descriptions of exiguous fossil record, monotonous mineralogy, and intractable chemistry. Since 1978 expanded efforts have yielded much new informati
Authors
R. K. Leininger, J.G. Hailer, N.R. Shaffer

COORDINATION OF FEDERAL DIGITAL CARTOGRAPHIC ACTIVITIES.

Throughout the Federal Government, applications are emerging for spatial data bases that require digital cartographic data as a framework. This paper describes some major applications of spatial data in the Federal Government, and it discusses the extent to which these data needs are being coordinated. Efforts are outlined towards further coordination of digital cartographic data bases and product
Authors
R.B. Southard, L.L. Amos, Kirk E. Anderson

DEFINITION FOR ASBESTOS.

A definition of asbestos is proposed. Under this definition, the term asbestos applies to six naturally occurring minerals exploited commercially for their desirable physical properties, which are in part derived from their asbestiform habit. The six minerals are the serpentine mineral chrysotile and the amphibole minerals grunerite asbestos (also referred to as amosite), riebeckite asbestos (also
Authors
Malcolm Ross, Richard A. Kuntze, Robert A. Clifton

DEFINITION FOR TALC.

Talc is a naturally occurring single-phase mineral having the approximate chemical formula Mg//3Si//4O//1//0(OH)//2 and a specific type of crystal structure. Talc commonly forms by hydrothermal alteration of rocks rich in magnesium and iron (ultramafic rocks) and by low-grade thermal metamorphism of siliceous dolomites. The fact that talc often occurs in association with other minerals, or that it
Authors
Malcolm Ross