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The Baykit High province consists of two principal structural units?the Baykit regional high in the west, which occupies most of the province, and the Katanga structural saddle in the east. The province is on the western margin of the Siberian craton east of theYenisey Ridge foldbelt. The province is an exploration...

A pilot-scale study was conducted by the U.S. Army National Guard (USANG) at the Massachusetts Military Reservation (MMR) on Cape Cod, Massachusetts, to assess the use of a hydraulic-fracturing method to create vertical, permeable walls of zero-valent iron to passively remediate ground water contaminated with chlorinated solvents. The study was...

The Gulf Coast regional aquifer systems constitute one of the largest, most complicated, and most interdependent aquifer systems in the United States. Ground-water flow in a 230,000-square-mile area of the south-central United States was modeled for the effect of withdrawing freshwater at the rate of nearly 10 billion gallons per...

Exposed channel banks along distributaries of the lower Snohomish delta in the Puget Lowland of Washington reveal evidence of at least three episodes of liquefaction, at least one event of abrupt subsidence, and at least one tsunami since ca. A.D. 800. The 45 measured stratigraphic sections consist mostly of 2–4...

The Hawaiian Islands, with their unique geological history and geographic position, provide an excellent natural laboratory in which to evaluate currently competing biological (BSC) and phylogenetic (PSC) concepts of the species. Although the BSC as historically applied in archipelagic situations is shown to be flawed in producing overlumped polytypic species,...

The Central Weather Bureau (CWB) of Taiwan completed a deployment of 1200 modern digital strong-motion instruments in 1996 at free-field sites and in buildings and bridges. Consequently, a very extensive set of strong-motion records were obtained for the MW = 7.6 Chi-Chi earthquake in 1999, including over 60 near-field records...

For many oil and gas fields, estimates of ultimate recovery (the sum of cumulative production plus estimated reserves) tend to increase from one year to the next, and the gain is called reserve growth. Forecasts of reserve growth by the U.S. Geological Survey rely on statistical analyses of historical records...

A two-dimensional, cross-sectional, finite-difference, ground-water flow model and a simple application of Darcy?s law were used to quantify ground-water flow (from a wetlands) beneath Levee 30 in Miami-Dade County, Florida. Geologic and geophysical data, vertical seepage data from the wetlands, canal discharge data, ground-water-level data, and surface-water-stage data collected during...

Oil test wells can provide information on the depth, age, inclination, porosity, permeability, density, faulting, folding, and organic content of geologic formations mapped at the surface, or on units not recognized in surface outcrops. Formation density, as expressed in sonic and density logs commonly obtained when wells are drilled, has...

The Thematic Mapper (TM) instruments onboard Landsats 4 and 5 provide high-quality imagery appropriate for many different applications, including land cover mapping, landscape ecology, and change detection. Precise calibration was considered to be critical to the success of the Landsat 7 mission and, thus, issues of calibration were given high...

We present the application of Linear Programming for estimating biomass fluxes in ecosystem and food web models. We use the herpetological assemblage of the Everglades as an example. We developed food web structures for three common Everglades freshwater habitat types: marsh, prairie, and upland. We obtained a first estimate of...

The Caloosahatchee River Basin, located in southwestern Florida, includes about 1,200 square miles of land. The Caloosahatchee River receives water from Lake Okeechobee, runoff from the watershed, and seepage from the underlying ground-water systems; the river loses water through drainage to the Gulf of Mexico and withdrawals for public-water supply...

The quantification of current patterns is an essential component of a Water Quality Analysis Simulation Program (WASP) application in a riverine environment. The U.S. Geological Survey (USGS) provided a field validated two-dimensional Resource Management Associates-2 (RMA-2) hydrodynamic model capable of quantifying the steady-flowpatterns in the Ohio River extending from river...

We developed an individual-based model of Rabbit Viral Hemorrhagic Disease (RVHD) for European wild rabbits (Oryctolagus cuniculus L.), representing up to 1000 rabbits in four hectares. Model output for productivity and recruitment matched published values. The disease was density-dependent and virulence affected outcome. Strains that caused death after several days produced...

The overarching goal of this project is to build a spatially distributed infrastructure for information science research by forming a team of information science researchers and providing them with similar hardware and software tools to perform collaborative research. Four geographically distributed Centers of the U.S. Geological Survey (USGS) are developing their...

Water-temperature data from 32 sites in the Cook Inlet Basin, south-central Alaska, indicate various trends that depend on watershed characteristics. Basins with 25 percent or more of their area consisting of glaciers have the coldest water temperatures during the open-water season, mid-May to mid-October. Streams and rivers that drain lowlands...

A statewide study was conducted to develop regression equations for estimating flood-frequency discharges for ungaged stream sites in Iowa. Thirty-eight selected basin characteristics were quantified and flood-frequency analyses were computed for 291 streamflow-gaging stations in Iowa and adjacent States. A generalized-skew-coefficient analysis was conducted to determine whether generalized skew coefficients...

Data on the chemical composition of soil-water samples were collected quarterly from three watersheds in Shenandoah National Park, Virginia, from September 1999 through July 2000. The soil-water samples were analyzed for specific conductance and concentrations of sodium, potassium, calcium, magnesium, ammonium, chloride, nitrate, sulfate, acid-neutralizing capacity, silica, and total monomeric...

Changes in soil and vegetation management can impact strongly on the rates of carbon (C) accumulation and loss in soil, even over short periods of time. Detecting the effects of such changes in accumulation and loss rates on the amount of C stored in soil presents many challenges. Consideration of...

A method of updating flood inundation maps at a fraction of the expense of using traditional methods was piloted in Washington State as part of the U.S. Geological Survey Urban Geologic and Hydrologic Hazards Initiative. Large savings in expense may be achieved by building upon previous Flood Insurance Studies and...

An analytical method using high-performance liquid chromatography/mass spectrometry (HPLC/MS) was developed by the U.S. Geological Survey in 1999 for the analysis of selected chloroacetanilide herbicide degradation compounds in water. These compounds were acetochlor ethane sulfonic acid (ESA), acetochlor oxanilic acid (OXA), alachlor ESA, alachlor OXA, metolachlor ESA, and metolachlor OXA....

Rapid video measurements of foreshore morphology and velocity were collected at Duck, NC in 1997 to investigate sediment transport processes in the swash zone. Estimates of foreshore evolution over a roughly 30 m cross-shore by 80 m alongshore study area were determined using a stereogrammetric technique. During the passage of...

Microbial calcification has been identified as a significant source of carbonate sediment production in modern marine and lacustrine environments around the globe. This process has been linked to the production of modern whitings and large, micritic carbonate deposits throughout the geologic record. Furthermore, carbonate deposits believed to be the result...