Conference Papers

The discharge and volume of flow in a peak decrease as the peak moves through an 89-mile (143 km) reach of the Santa Cruz River. An average of three peaks per year flow the length of the reach. Of 17,500 acre-ft (21,600 dam**3) that entered the upstream end of the reach, 2300 acre-ft (2,840 dam**3), 13 percent of the inflow, left the reach as streamflow. The remainder was lost through...

Two experiments were conducted in conjunction with a 23-day aquifer test made in south-central Arizona to determine (1) water loss from a natural channel and (2) flow through a 330-foot-thick unsaturated zone overlying an unconfined aquifer. The experiments provided control for the aquifer test plus results relative to arid land hydrology. The increases of soil moisture within the 330...

A variety of in-stream experiments have been conducted in small, mountain streams to investigate in-stream solute transport, interactions between surface and subsurface flows, and geochemical interactions between solutes and sediments. Models for cation transport have been developed. The emphasis has been on attempting to demonstrate the relative roles of physical transport processes and

During the summer of 1983 and the spring and summer of 1984, the authors conducted side scan sonar and shallow subbottom surveys in conjunction with bathymetric and diving surveys along three northern California coastal structures to determine the condition of the structures before extensive damage occurred. Then the applicability of the data collection techniques for condition surveys...

Chance No. 1 was drilled to a depth of 245. 4 m and cased to a depth of 72. 2 m in 1961. Temperature logs were obtained in 1976, 1982, and 1983, with the casing open to the atmosphere. Water was boiling at the surface of the fluid column on each occasion. Temperatures within the upper part of the cased interval remained virtually identical over the 7-year period. The small differences...

Tests were performed to investigate the geometric characteristics of Landsat 4 images. The first set of tests was designed to determine the extent of image distortion caused by the physical process of writing the Landsat 4 images on film. The second was designed to characterize the geometric accuracies inherent in the digital images themselves. Test materials consisted of film images of...

The U.S. Geological Survey conducts research and collects hydrologic data relating to the Nation's water resources. Two water quality laboratories in Atlanta, Georgia, and Denver, Colorado, support the national research programs, and provide chemical analyses of natural waters for the data program. Additional chemical water quality data are provided by cooperator and contract...

Two U. S. Geological Survey computer programs are modified and linked to predict the cumulative impact of iron and manganese oxidation in coal-mine discharge on the dissolved-chemical quality of a receiving stream. The coupled programs calculate the changes in dissolved-iron, dissolved-manganese, and dissolved-oxygen concentrations, and the pH of surface water downstream from the...

A small-diameter three-component fluxgate magnetometer probe with gyroscopic and inclinometer orientation has been developed to meet U. S. Geological Survey design and performance specifications for measurement of the direction and intensity of the Earth's magnetic field in vertical and inclined boreholes. The orthogonal fluxgate magnetometer elements have a measurement resolution of 10...

A three-dimensional high-resolution seismic study of the summit caldera of Newberry Volcano, Oregon, was conducted by the U. S. Geological Survey using an adaptation of the method applied by Nercessian et al. , (1984). Preliminary interpretation of the traveltime residuals reveals a ring of high P-velocity material coinciding with the inner ring fault system of the caldera in the upper 2...

Plane-strain solutions are used to analyze the influence of topography on the state of stress at Yucca Mountain, Nye County, Nevada. The results are in good agreement with the measured stress components obtained in drill holes by the hydraulic-fracturing technique, particularly those measured directly beneath the crest of the ridge, and indicate that these stresses are gravitationally...

Transient electromagnetic soundings were used to map the geoelectrical structure of Newberry Volcano in central Oregon. An extensive conductor was found to underlie the volcano and to have resistivities from 20 OMEGA m to 72 OMEGA m. The depth to the conductor ranges from 410 m to 870 m. Inside the caldera, low basement resistivities are the result of hot fluids. The cause of the...