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New 1:24,000-scale geologic mapping in the Silt 7.5' quadrangle, in support of the USGS Western Colorado I-70 Corridor Cooperative Geologic Mapping Project, provides new interpretations of the stratigraphy, structure, and geologic hazards in the area of the southwest flank of the White River uplift, the Grand Hogback, and the eastern...

In 1995, the USGS estimated a mean resource of 114 trillion cubic feet of undiscovered technically recoverable natural gas in plays deeper than 15,000 feet/4,572 meters in onshore regions of the United States. This volume summarizes major conclusions of ongoing work. Chapters A and B address the areal extent of...

This report is an evaluation of oil and gas resources for petroleum systems of the Putumayo-Oriente-Maranon province of Columbia, Ecuador, and Peru. This assessment is a product of the World Energy Project of the U.S. Geological Survey, under the direction of Thomas Ahlbrandt. Described in this explanation of the petroleum...

This volume is a compilation of significant floods that occurred throughout the United States, Puerto Rico, and the Virgin Islands during 1970 through 1989. A summary of most devastating floods according to amount of damage and lives lost is provided for each year. State-by-state compilations include a description of the...

This report provides semi-quantitative data on modes of occurrence of 19 elements in as-mined Powder River Basin coal and its corresponding simulated cleaned coal. The data are in support of the project "Prediction of Trace Element Removal from Coal" --a Cooperative Research and Development Agreement (CRADA) with CQ Inc. The...

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...

Ground-water models attempt to represent an actual ground-water system with a mathematical counterpart. The conceptualization of how and where water originates in the ground-water-flow system and how and where it leaves the system is critical to the development of an accurate model. The mathematical representation of these boundaries in the...

Federally owned coal plays a major role in the energy supply of the United States. About 1.1 billion tons of coal were produced in the United States in 1997 (U.S. Department of Energy, 1998). About 30 percent of that total, or about 330 million tons,1 came from Federal lands. (See...

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:...

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...

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...

The purpose of this study is to characterize natural occurrences of petroleum at the surface and in the subsurface within northern California in order to define and map petroleum systems for U.S. Geological Survey energy resource assessments. Furthermore, the chemical characterization and mapping of natural petroleum occurrences could also be...

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...

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...

No abstract available....