Conference Papers

The Federal Highway Administration sponsored a laboratory research at Colorado State University and field data collection with the US Geological Survey, to evaluate the effects of bed material on the depth of scour. Correction factors are compared to include the effect of bed material in the HEC-18 equation. The HEC-18 equation tends to overpredict the observed scour for streams with coarse bed ma

Ice and ice-borne sediments were collected across the Arctic Basin during the Arctic Ocean Section, 1994 (AOS-94), a recent US/Canada trans- Arctic expedition. Sediments were analysed for 137Cs, clay mineralogy and carbon. Concentrations of 137Cs ranged from 5 to 73 Bq kg-1 in the ice- borne sediments. Concentrations of ice samples without sediment were all less than 1 Bq m-3. The sediment sample

The molecular and elemental composition of immature kerogens isolated from Upper Cretaceous marine carbonates from Sergipe Basin, Brazil were investigated using combined pyrolysis-gas chromatography/mass spectrometry and organic petrographic techniques. The kerogens are predominantly composed of reddish-fluorescing amorphous organic matter (AOM) and variable amounts of yellow-fluorescing alginite

Extensive faulting is observed in sediments containing high concentrations of methane hydrate off the southeastern coast of the United States. Faults that break the sea floor show evidence of both extension and shortening; mud diapirs are also present. The zone of recent faulting apparently extends from the ocean floor down to the base of gas-hydrate stability. We infer that the faulting resulted

The U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers, Chicago District did field-scale tests in August-September 1996 to determine mixing patterns associated with different configurations of coarse-bubble air diffusers. The tests were done in an approximately 13-meter deep quarry near Chicago, Ill. Three-dimensional velocity, water-temperature, dissolved oxygen concentra

In July 1994, parts of central and southwestern Georgia, southeastern Alabama, and the western panhandle of Florida were devastated by floods resulting from rainfall produced by Tropical Storm Alberto. Entire communities were inundated by flood waters as numerous streams reached peak stages and discharges far greater than previous floods in the Flint, Ocmulgee, and Choctawhatchee River basins. The

Forecasting the likelihood of drought conditions is an integral part of managing a water supply storage and delivery system. Position analysis uses a large number of possible flow sequences as inputs to a simulation of a water supply storage and delivery system. For a given set of operating rules and water use requirements, water managers can use such a model to forecast the likelihood of specifie

The amount of natural gas within the gas hydrate accumulations of the world is believed to greatly exceed the volume of known conventional natural gas reserves. The hydrocarbon production history of the Russian Messoyakha field, located in the West Siberian Basin, has been used as evidence that gas hydrates are an immediate source of natural gas that can be produced by conventional means. Re-exami

No abstract available

Geologic, pedologic, and climatic factors, including radium content, grain size, siting of radon parents within soil grains or on grain coatings, and soil moisture conditions, determine a soil's emanating power and radon transport characteristics. Data from field studies indicate that soils derived from similar parent rocks in different regions have significantly different emanation coefficients d

Measurements of geotechnical properties of various poorly sorted debris-flow sediments and slurries (??? 32 mm diameter) emphasize their granular nature, and reveal that properties of slurries can differ significantly from those of compacted sediments. Measurements show that: (1) cohesion probably offers little resistance to shear in most debris flows under low confining stresses normally found in

No abstract available.