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This report describes tests conducted at Bonneville Dam on the Columbia River in the spring of 2000. The studies used three-dimensional (3D) acoustic telemetry and computational fluid dynamics (CFD) hydraulic modeling techniques to evaluate the response of outmigrating juvenile steelhead (Oncorhynchus mykiss) and yearling chinook (O. tshawytscha) to the Prototype...

Interpretation of paleoclimate records requires an understanding of Earth’s climate system, the causes (forcings) of climate changes, and the processes that amplify (positive feedback) or damp (negative feedback) these changes. Paleoclimatologists reconstruct the history of climate from proxies, which are those characteristics of sedimentary deposits that preserve paleoclimate information. A...

A comprehensive set of soil characteristics were examined to determine the effect of soil on the transport of agrichemicals to groundwater. This paper examines the relation of soil characteristics to concentrations and occurrence nitrate, atrazine, and atrazine residue from 99 wells completed in unconsolidated aquifers across the Midwestern United States....

No abstract available....

Increases in atmospheric greenhouse gases are driving significant changes in global climate. To project potential vegetation response to future climate change, this study uses response surfaces to describe the relationship between bioclimatic variables and the distribution of tree and shrub taxa in western North America. The response surfaces illustrate the...

Nomad was deployed for a 45 day traverse in the Atacama Desert, Chile, during the summer of 1997. During this traverse, 1 week was devoted to science experiments. The goal of the science experiments was to test different planetary surface exploration strategies that included (1) a Mars mission simulation, (2)...

Eleven streams in the Wapsipinicon, Cedar, Iowa, and Skunk River basins in eastern Iowa were sampled monthly from March 1996 through September 1998 to assess the occurrence, distribution, and transport of nitrogen, phosphorus, and suspended sediment as part of the U.S. Geological Survey's National Water-Quality Assessment Program. At least one...

Numerical-simulation and optimization techniques were used to evaluate alternatives for the conjunctive management of ground- and surface-water resources of the Hunt­-Annaquatucket­-Pettaquamscutt stream-aquifer system in central Rhode Island. Ground-water withdrawals from the Hunt-Annaquatucket-Pettaquamscutt aquifer exceeded 8 million gallons per day during months of peak water use during 1993­98, and additional withdrawals...

For information on historic asbestos mines, historic prospects and natural asbestos occurrences in the U.S., see: Eastern U.S. ---> Open-File Report 2005-1189 (http://pubs.usgs.gov/of/2005/1189/); Central U.S. ---> Open-File Report 2006-1211 (http://pubs.usgs.gov/of/2006/1211/); Rocky Mountain States ---> Open-File Report 2007-1182 (http://pubs.usgs.gov/of/2007/1182/); Southwest U.S. ---> Open-File Report 2008-1095 (http://pubs.usgs.gov/of/2008/1095/). For commodity statistics and information see:...

New 1:24,000-scale geologic mapping in the Colorado National Monument Quadrangle and adjacent areas, in support of the USGS Western Colorado I-70 Corridor Cooperative Geologic Mapping Project, provides new interpretations of and data for the stratigraphy, structure, geologic hazards in the area from the Colorado River in Grand Valley onto the...

Understanding the links between land-use changes and physical stream habitat responses is of increasing importance to guide resource management and stream restoration strategies. Transmission of runoff and sediment to streams can involve complex responses of drainage basins, including time lags, thresholds, and cumulative effects. Land-use induced runoff and sediment yield...

No abstract available....

Introduction In recent years, the health of the entire coral reef ecosystem that lines the outer shelf off the Florida Keys has declined markedly. In particular, loss of those coral species that are the building blocks of solid reef framework has significant negative implications for economic vitality of the region. What are the reasons for this decline? Is it due...

Gas hydrates are naturally occurring icelike solids in which water molecules trap gas molecules in a cagelike structure known as a clathrate. Although many gases form hydrates in nature, methane hydrate is by far the most common; methane is the most abundant natural gas. The volume of carbon contained in...

Northern Arizona's San Francisco Volcanic Field, much of which lies within Coconino and Kaibab National Forests, is an area of young volcanoes along the southern margin of the Colorado Plateau. During its 6-million-year history, this field has produced more than 600 volcanoes. Their activity has created a topographically varied landscape...

The Alaska National Interest Lands Conservation Act (1980) established the Arctic National Wildlife Refuge (ANWR). In section 1002 of that act, Congress deferred a decision regarding future management of the 1.5-million-acre coastal plain ("1002 area") in recognition of the area’s potentially enormous oil and gas resources and its importance...

The area currently known as the National Petroleum ReserveAlaska was originally designated in 1923 as Naval Petroleum Reserve No. 4 (NPR4). It was one of four U.S. regions thought to contain significant amounts of oil that were to be reserved for national crises. Geographic and geologic knowledge of the NPR4...

The Roseburg 30' x 60' Quadrangle covers the southeastern margin of the Oregon Coast Range and its tectonic boundary with Mesozoic terranes of the Klamath Mountains (see figures 1 and 2 in pamphlet, also shown on map sheet). The geologic framework of the Roseburg area was established by the pioneering...

Our Nation faces the simultaneous challenges of increasing demand for energy, declining domestic production from existing oil and gas fields, and increasing expectations for environmental protection. The Energy Information Administration (2000) forecasts that worldwide energy consumption will increase 32 percent between 1999 and 2020 because of growth of the world...