Skip to main content
USGS - science for a changing world
Advanced Search

Filters: Categories: Publication (X) > partyWithName: U.S. Govt. Print. Off., (X)

2,719 results (17ms)   

View Results as: JSON ATOM CSV
thumbnail
A coupled flow-temperature model has been developed and verified for a 27.9-km reach of the Chattahoochee River between Buford Dam and Norcross, Ga. Flow in this reach of the Chattahoochee is continuous but highly regulated by Buford Dam, a flood-control and hydroelectric facility located near Buford, Ga. Calibration and verification utilized two sets of data collected under highly unsteady discharge conditions. Existing solution techniques, with certain minor improvements, were applied to verify the existing technology of flow and transport modeling. The linear, implicit finite-difference flow model was calibrated by use of a depth profile obtained at steady low flow and unsteady flow data obtained in March 1976....
Categories: Publication; Types: Citation; Tags: Professional Paper
thumbnail
Mount St. Helens has been more active and more explosive during the last 4,500 years than any other volcano in the conterminous United States. Eruptions of that period repeatedly formed domes, large volumes of pumice, hot pyroclastic flows, and, during the last 2,500 years, lava flows. Some of this activity resulted in mudflows that extended tens of kilometers down the floors of valleys that head at the volcano. This report describes the nature of the phenomena and their threat to people and property; the accompanying maps show areas likely to be affected by future eruptions of Mount St. Helens. Explosive eruptions that produce large volumes of pumice affect large areas because winds can carry the lightweight material...
Categories: Publication; Types: Citation; Tags: Bulletin
thumbnail
The present report describes the results of a hydrogeologic reconnaissance in the Mekong Delta region by the writer, a hydrogeologist of the U.S. Geological Survey, while on assignment as an adviser to the Vietnamese Directorate of Water Supply from October 1968 to April 1970 under the auspices of the U.s. Agency for International Development. The delta of the Mekong River, comprising an area of about 70,000 square kilometres in South Vietnam and Cambodia, is an almost featureless plain rising gradually from sea level to about 5 metres above sea level at its apex 300 kilometres inland. Most of the shallow ground water in the Holocene Alluvium of the delta in Vietnam is brackish or saline down to depths of 50 to...
Categories: Publication; Types: Citation; Tags: Water Supply Paper
thumbnail
Measurements of the Reynolds stresses and the mean motion pattern were made in a uniform turbulent motion in a conduit consisting of a large, nearly square section joined by a smaller rectangular section. The results indicate that the boundary shearing stress is nearly constant over large segments of the boundaries. The magnitudes of the lateral and the vertical components of turbulence are not the same near a boundary and the component normal to the boundary is smaller than the component parallel to the boundary. The difference in the two components in the corner regions of the channel produces secondary mean motions in the plane of the channel section. The strength of the motion depends upon the angle subtended...
Categories: Publication; Types: Citation; Tags: Professional Paper
thumbnail
The sediment-transport characteristics of streams were determined in a 15,500-square-kilometre (6,000-square-mile) area of the Coastal Plain and Piedmont regions of eastern North Carolina during 1969-73. The study covered all or parts of 21 counties and included data for 28 sediment-sampling stations in parts of 4 major river basins?the Roanoke, Pamlico, Neuse, and Cape Fear. Annual suspended-sediment yields ranged from 117 to 4.2 tonnes per square kilometre (333 to 12 tons per square mile). Streams in the Piedmont region have the highest yields. Suspended-sediment yield decreases in an eastward direction from the Piedmont to the Coastal Plain region. Sediment characteristics are directly affected by topography,...
Categories: Publication; Types: Citation; Tags: Water Supply Paper
thumbnail
For nearly half a century the Willamette River in Oregon experienced severe dissolved-oxygen problems related to large loads of organically rich waste waters from industries and municipalities. Since the mid-1950 's dissolved oxygen quality has gradually improved owing to low-flow augmentation, the achievement of basinwide secondary treatment, and the use of other waste-management practices. As a result, summer dissolved-oxygen levels have increased, salmon runs have returned, and the overall effort is widely regarded as a singular water-quality success. To document the improved dissolved-oxygen regimen, the U.S. Geological Survey conducted intensive studies of the Willamette during the summer low-flow seasons of...
Categories: Publication; Types: Citation; Tags: Circular
thumbnail
Concentrations of organic matter in the general range of 1-10 milligrams per litre organic carbon are common in natural water, and many naturally occurrin7 organic compounds form aluminum complexes. The aluminum concentrations in near-neutral pH solutions may be 10-100 times higher than the values predicted from solubility data if formation of such organic complexes is ignored. The processes of polymerization of aluminum hydroxide and precipitation of gibbsite are inhibited by the presence of the organic flavone compound quercetin in concentrations as low as 10 x -5.3 mole per litre. Quercetin forms a complex, with a probable molar ratio of 1:2 aluminum to quercetin, that has a formation constant (f12) of about...
Categories: Publication; Types: Citation; Tags: Water Supply Paper
thumbnail
Aqueous aluminum solutions containing 4.5 ? 10 4 molar aluminum in 0.01 molar NaC104 were partly neutralized with NaOH to give OH:A1 mole ratios from 1.40 to 2.76. Measured amounts of montmorillonite, kaolinite, volcanic ash, or feldspathic sand were added to provide an area of inert surface. Reactions that occurred during 100 days of aging were compared with those in similar solutions without added surfaces, studied in earlier work. Adsorption of monomeric species Al(H20)6+3, AlOH(H2O)5+2, and Al(OH)2(H2O 4? on the added surfaces follows a cation exchange mass law equilibrium model, and adsorption is essentially complete in 1 hour. Only minor changes in monomeric aluminum species occurred after that. Rapid adsorption...
Categories: Publication; Types: Citation; Tags: Water Supply Paper