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The U.S. Geological Survey (USGS) acquired two 1.4-km-long, high-resolution (~5 m vertical resolution) seismic-reflection lines in 2006 that cross near the International Continental Scientific Drilling Program (ICDP)-USGS Eyreville deep drilling site located above the late Eocene Chesapeake Bay impact structure in Virginia, USA. Five-meter spacing of seismic sources and geophones...

The 6-hectare (ha) freshwater tidal Anacostia River Fringe Wetlands (Fringe Wetlands) were reconstructed along the mainstem of the Anacostia River in Washington, DC (Photograph 1, Figure 1) during the summer of 2003. The Fringe Wetlands consist of two separate planting cells. Fringe A, located adjacent to Lower Kingman Island, on...

Although introduced species often interact with one another in their novel communities, the role of parasites in these interactions remains less clear. We examined parasite richness and prevalence in 2 shorecrab species with different invasion histories and residency times in an introduced region where their distributions overlap broadly. On the...

Ground water is the sole source of drinking water within Tooele Valley. Transition from agriculture to residential land and water use necessitates additional understanding of water resources. The ground-water basin is conceptualized as a single interconnected hydrologic system consisting of the consolidated-rock mountains and adjoining unconsolidated basin-fill valleys. Within the...

These remotely sensed, geographically referenced elevation measurements of Lidar-derived first surface (FS) topography were produced collaboratively by the U.S. Geological Survey (USGS), Florida Integrated Science Center (FISC), St. Petersburg, FL, and the National Aeronautics and Space Administration (NASA), Wallops Flight Facility, VA. This project provides highly detailed and accurate datasets of...

Mille Lacs Lake and its tributaries, located in east-central Minnesota, are important resources to the public. In addition, many wetlands and lakes that feed Mille Lacs Lake are of high resource quality and vulnerable to degradation. Construction of a new four-lane expansion of U.S. Highway 169 has been planned along...

Comprehensive planning for water resources development and use in Oklahoma requires a historical perspective on water resources. The U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board, summarized the 1950-2005 water-use information for Oklahoma. This report presents 1950-2005 estimates of freshwater withdrawal for water use in Oklahoma by...

Oil spillage from natural sources is very common in the waters of southern California. Active oil extraction and shipping is occurring concurrently within the region and it is of great interest to resource managers to be able to distinguish between natural seepage and anthropogenic oil spillage.The major goal of this...

A study to characterize the groundwater-flow system in four tributary subbasins and vicinity of the lower Skagit River basin was conducted by the U.S. Geological Survey to assist Skagit County and the Washington State Department of Ecology in evaluating the effects of potential groundwater withdrawals and consumptive use on tributary...

We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of...

Uranium (U) concentrations in groundwater in several parts of the eastern San Joaquin Valley, California, have exceeded federal and state drinking water standards during the last 20 years. The San Joaquin Valley is located within the Central Valley of California and is one of the most productive agricultural areas in...

"The Great Salt Lake (GSL) of Utah, USA, is the largest saline lake in North America, and its brines are some of the most concentrated anywhere in the world. The lake occupies a closed basin system whose chemistry reflects solute inputs from the weathering of a diverse suite of rocks in its drainage...

Mass balance models of dissolved gases in streams, lakes, and rivers serve as the basis for estimating wholeecosystem rates for various biogeochemical processes. Rates of gas exchange between water and the atmosphere are important and error-prone components of these models. Here we present a simple and efficient modification of the...

Despite accelerating globalization, most people still eat food that is grown locally. Developing countries with weak purchasing power tend to import as little food as possible from global markets, suffering consumption deficits during times of high prices or production declines. Local agricultural production, therefore, is critical to both food security...

An in situ experiment was performed in a shallow alluvial aquifer in Maryland to quantify the fractionation of stable isotopes in perchlorate (Cl and O) and nitrate (N and O) during biodegradation. An emulsified soybean oil substrate that was previously injected into this aquifer provided the electron donor necessary for...

The Great Lakes Science Center of the United States Geological Survey (USGS) is working cooperatively with the Ontario Ministry of Natural Resources (OMNR) on a threeyear study to develop standard procedures for acoustic and midwater trawl (AC-MT) assessments of spawning cisco Coregonus artedi that the OMNR can carry forward as...

In this field trip, we provide a review of the significant controversy concerning the timing of deglaciation in the Hudson and Wallkill Valleys. We outline the differences in methodology and chronology with a circular route throughout the Hudson and Wallkill valleys. We begin the trip at Lake Mohonk near New...

In southeastern New York Middle Silurian Shawangunk Formation (Figure 1), containing gray conglomerate, sandstone and shale, lies unconformably above the Ordovician Martinsburg Formation, consisting of shales and graywackes. In southwestern New York, near the Port Jervis area, The Shawangunk Formation is overlain by the Bloomsburg Red Beds, the same stratigraphic...

Electron microprobe analyses are presented of chevkinite-group minerals from Canada, USA, Guatemala, Norway, Scotland, Italy and India. The host rocks are metacarbonates, alkaline and subalkaline granitoids, quartz-bearing pegmatites, carbonatite and an inferred K-rich tuff. The analyses extend slightly the range of compositions in the chevkinite group, e.g. the most...

Extending nearly 400 km from Sabine Pass on the Texas-Louisiana border east to the Chandeleur Islands, the Louisiana coastal zone (Fig. 11.1) along the north-central Gulf of Mexico is the southern terminus of the largest drainage basin in North America (>3.3 million km2), which includes the Mississippi River delta plain...

Streamflow-characteristic estimation methods for unregulated rivers and streams of Tennessee were developed by the U.S. Geological Survey in cooperation with the Tennessee Department of Environment and Conservation. Streamflow estimates are provided for 1,224 stream sites. Streamflow characteristics include the 7-consecutive-day, 10-year recurrence-interval low flow, the 30-consecutive-day, 5-year recurrence-interval low flow,...

Federally endangered Lost River sucker Deltistes luxatus and shortnose sucker Chasmistes brevirostris were once abundant throughout their range but populations have declined; they have been extirpated from several lakes, and may no longer reproduce in others. Poor recruitment into the adult spawning populations is one of several reasons cited for...

A study was conducted by the U.S Geological Survey in cooperation with the Arkansas State Highway and Transportation Department to characterize the source and hydrogeologic conditions responsible for thermal water in a domestic well 5.5 miles east of Hot Springs National Park, Hot Springs, Arkansas, and to determine the degree...

Most probabilistic seismic-hazard assessments require an estimate of Mmax, the magnitude (M) of the largest earthquake that is thought possible within a specified area. In seismically active areas such as some plate boundaries, large earthquakes occur frequently enough that Mmax might have been observed directly during the historical period. In...

Upscaling the spatial and temporal changes of carbon stocks and fluxes from sites to regions is challenging owing to the spatial and temporal variances and covariance of driving variables and the uncertainties in both the model and the input data. Although various modeling approaches have been developed to facilitate the...