Publications

No abstract available.

No abstract available.

We use three-dimensional elastic models to help guide the kinematic interpretation of crustal deformation associated with strike-slip faults. Deformation of the brittle upper crust in the vicinity of strike-slip fault systems is modeled with the assumption that upper crustal deformation is driven by the relative plate motion in the upper mantle. The driving motion is represented by...

An understanding of the mechanisms of oxygen (02) transport in unsaturated mine spoil is necessary to design and implement effective measures to exclude 02 from pyritic materials and to control the formation of acidic mine drainage. Partial pressure of oxygen (Po2) in pore gas, chemistry of pore water, and temperature were measured at different depths in unsaturated spoil at two...

Bayesian models provide a structure for studying collections of parameters such are considered in the investigation of communities, ecosystems, and landscapes. This structure allows for improved estimation of individual parameters by considering them in the context of a group of related parameters. Individual estimates are differntially adjusted toward in overall mean, with the magnitude...

The U.S. Geological Survey, in cooperation with the Susquehanna River Basin Commission and the Pennsylvania Department of Environmental Resources, investigated the effects of agricultural best-management practices on surface-water quality as part of the U.S. Environmental Protection Agency's Chesapeake Bay Program. This report characterizes a 0.63-square- mile agricultural watershed...

We have replaced the usual band of poor-quality data in the near-nadir region of our GLORIA long-range sidescan-sonar imagery with a shaded-relief image constructed from swath bathymetry data (collected simultaneously with GLORIA) which completely cover the nadir area. We have developed a technique to enhance these "pseudo-sidescan" images in order to mimic the neighbouring GLORIA...

Hydrologic and water-quality data were collected from a precipitation-collection station and from two small watersheds on Catoctin Mountain, north-central Maryland, as part of investigations of acidic deposition and episodic acidification, and their effects on streamwater quality. Detailed descriptions of the site instrumentation in the watersheds, field data-collection techniques, and...

Hydrologic and water-quality data were collected at a precipitation-collection station and from two small watersheds on Catoctin Mountain, north- central Maryland, as part of an investigation of episodic acidification and its effects on streamwater quality. Data were collected from June 1990 through December 1993. Descriptions of the water shed instrumentation, data-collection techniques...

Water quality in the headwaters of the Little Conestoga Creek, Lancaster County, Pa., was investigated from April 1986 through September 1989 to determine possible effects of agricultural nutrient management on water quality. Nutrient management, an agricultural Best-Management Practice, was promoted in the 5.8-square-mile watershed by the U.S. Department of Agriculture Rural Clean Water...

Twenty bridge sites in Indiana were evaluated to determine: the extent of scour during floods, streambed stability, the maximum historical scour, and estimates of potential scour. Historical scour data were collected by means of geophysical methods and used to evaluate the scour-computation procedures recommended by the U.S. Federal Highway Administration and 13 other published pier...

Developments in Acoustic Doppler Current Profiler (ADCP) technologies have made these instruments potentially useful for making measurements of discharge in rivers and large streams. Although there have been several laboratory studies and some field experiments, quantitative information on the performance of ADCP's under field conditions is relatively rare but essential to proper...