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The record flood on the Mississippi River during the summer of 1993 provided a rare opportunity to collect data on scour of the streambed at bridges and to test data collection equipment under extreme hydraulic conditions. Detailed bathymetric and hydraulic information were collected at two bridges crossing the Mississippi River...

No abstract available....

The lower Eocene Willwood Formation in the Bighorn Basin of Wyoming preserves a rich and diverse mammalian and floral record. The paleomagnetic behavior of the sequence of floodplain paleosols of varying degrees of maturation ranges from excellent to poor. We present a...

Version 2.0 of JKPLOT is a simple, device-independent plotting system that can provide a base for building plotting facilities tailored to the needs of geologists. The programs were written in Microsoft QuickBasic for use on equipment compatible with an IBM personal computer. The system provides subroutines and functions for plotting...

The establishment of steady unsaturated flow in a centrifuge permits accurate measurement of small values of hydraulic conductivity (K). This method can provide a recharge determination if it is applied to an unsaturated core sample from a depth at which gravity alone drives the flow. A K value determined at the in...

The Christy Ti-V-Nb deposit is hosted by the Arkansas Novaculite, adjacent to the carbonatite-alkaline Magnet Cove Complex. Mineralized rock contains up to 8 wt percent Ti, 2.68 wt percent V, and 0.124 wt percent Nb. Minor amounts of Li and Mo are present, and there is evidence for the preferential...

Water resources data for the 1993 water year for Wyoming consists of records of stage, discharge and water quality of streams; stage and contents of lakes and reservoirs, and water levels and water quality of ground water. This report contains discharge records for 190 gaging stations; stage and contents for...

An evaluation of historic flood estimates in mountainous areas in Colorado was made to assess their accuracy. The purpose of this evaluation is to enhance awareness of the need to assess the accuracy of historic flood peaks, particularly floods of record, because they are such a critical factor in flood-plain...

A textural sorting pattern is evident, with pronounced and regular changes in sand content throughout the strait but with consistent separation of silt from clay only at the lowest sand contents. Vane shear strength values fall in the very soft to medium range. They are best predicted by the amount...

This paper describes a general method for determining the amount of earthquake-induced landsliding that occurs in a seismically active region over time; this determination can be used as a quantitative measure of the long-term hazard from seismically triggered landslides as well as a measure of the importance of this process...

To test the hypothesis that siliciclastic rocks constituted the major source of Pb and Ba in barite-galena deposits of the Taconic Orogen, we determined Pb-isotope ratios in galena, barren rocks and contained minerals, as well as concentrations of Pb, U, Th and Ba in the latter (detrital feldspars, sandstones, mudstones,...

The Oquirrh fault zone is a range-front normal fault that bounds the east side of Tooele Valley and it has long been recognized as a potential source for large earthquakes that pose a significant hazard to population centers along the Wasatch Front...

The ionic tracers lithium, sodium, chloride and bromide were used to measure flow loss in a small stream (≈︁ 10 ls−1). An injectate containing all four tracers was added continuously at five sites along a 507 m study reach of St Kevin Gulch, Lake County, Colorado to determine which sections...

An active oceanic spreading ridge is being subducted beneath the South American continent at the Chile Triple Junction. This process has played a major part in the evolution of most of the continental margins that border the Pacific Ocean basin. A combination of high resolution swath bathymetric maps, seismic reflection...

No abstract available....

Saline seeps are an increasingly serious problem in semi-arid regions of the southwestern United States. They result when excessive recharge of the shallow ground water in soils raises the water table locally to within one meter of the land surface, and the salinity of the shallow water is increased through...

The computer program, RORA, allows automated analysis of streamflow hydrographs to estimate ground-water recharge. Output from the program, which is based on the recession-curve-displacement method (often referred to as the Rorabaugh method, for whom the program is named), was compared to estimates of recharge obtained...

Volcán Alcedo is one of the seven western Galápagos shields and is the only active Galápagos volcano known to have erupted rhyolite as well as basalt. The volcano stands 4 km above the sea floor and has a subaerial volume of 200 km3, nearly all of which is basalt. As...

Using fingerlings of brook trout Salvelinus fontinalis naturally infected with infectious pancreatic necrosis virus (IPNV), we demonstrated that elevated water temperature and treatment with the immunosuppressant triamcinolone acetonide (generic Kenalog®) significantly increases the titer of IPNV and probably also the prevalence of the infection. Stress-promoting treatments could potentially enhance the...

Middle Miocene siliciclastic deposits comprising the Calvert Cliffs section at the Baltimore Gas and Electric Company's (BG&E) nuclear power plant site in southern Maryland were analyzed in terms of lithostratigraphy, sedimentary structures, and granulometric parameters, to interprete paleo-environments within a sequence-stratigraphic framework. In terms of sequence-stratigraphic models, the BG&E section...

Shallow seismic reflection has been successfully applied to environmental problems in a variety of geologic settings. Increased dynamic range of recording equipment and decreased cost of processing hardware and software have made seismic reflection a cost-effective means of imaging shallow geologic targets. Seismic data possess sufficient resolution in many areas...

The effect of topography and rock mass anisotropy on gravitational stresses in long isolated symmetric ridges and valleys is modeled using an analytical method proposed earlier by the first two authors. The rock mass deforms under a condition of plane strain. A parametric study is presented on the effect of...