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Groundwater quality in the approximately 1,695-square-mile Central Eastside San Joaquin Basin (Central Eastside) study unit was investigated as part of the Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001,...

The Hayfork 15' quadrangle is located just west of the Weaverville 15' quadrangle in the southern part of the Klamath Mountains geologic province of northern California. It spans parts of six generally north-northwest-trending tectonostratigraphic terranes that are, from east to west, the Eastern Klamath, Central Metamorphic, North Fork, Eastern Hayfork,...

Two phases of deformation are needed to describe the Cenozoic tectonic evolution of the Pahrump and Mesquite basins in the southern Great Basin and eastern Mojave Desert, United States. By interpreting seismic reflection and gravity observations along with bedrock and surficial mapping, we infer an extensional phase of basin formation...

A variety of passive and semi-passive treatment systems were constructed by state and local agencies to neutralize acidic mine drainage (AMD) and reduce the transport of dissolved metals in the upper Swatara Creek Basin in the Southern Anthracite Coalfield in eastern Pennsylvania. To evaluate the effectiveness of selected treatment systems...

New detailed geologic mapping and geochronology of the Barstow Formation at Harvard Hill, 30 km east of Barstow, CA, help to constrain Miocene paleogeography and tectonics of the central Mojave Desert. A northern strand of the Quaternary ENE-striking, sinistral Manix fault divides the Barstow Formation at Harvard Hill into two...

We report new paleomagnetic results and 40Ar/39Ar ages from the Peach Spring Tuff (PST), a key marker bed that occurs in the desert region between Barstow, California, and Peach Springs, Arizona. The 40Ar/39Ar ages were determined using individual hand-picked sanidine crystals from ash-flow specimens used in previous paleomagnetic studies at eight sites...

Acidic mine drainage (AMD) from legacy anthracite mines has contaminated Swatara Creek in eastern Pennsylvania. Intermittently collected base-flow data for 1959–1986 indicate that fish were absent immediately downstream from the mined area where pH ranged from 3.5 to 7.2 and concentrations of sulfate, dissolved iron, and dissolved aluminum were as...

This report presents summary papers of work conducted between 2002 and 2007 under a 5-year project effort funded by the U.S. Geological Survey Mineral Resources Program, formerly entitled 'Tintina Metallogenic Province: Integrated Studies on Geologic Framework, Mineral Resources, and Environmental Signatures.' As the project progressed, the informal title changed from...

Water-quality samples were collected from the Upper Delaware Scenic and Recreational River (UPDE) and its tributaries during the period October 1, 2005, to September 30, 2007, to document existing water quality, determine relations between land use and water quality, and identify areas of water-quality concern. A tiered water-quality monitoring framework...

This report presents information used to characterize the groundwater-flow system in the Chambers-Clover Creek Watershed and vicinity, and includes descriptions of the geology and hydrogeologic framework; groundwater recharge and discharge; groundwater levels and flow directions; seasonal groundwater level fluctuations; interactions between aquifers and the surface-water system; and a water budget....

This report evaluates dissolved noble gas data, specifically helium-3 and helium-4, collected by the U.S. Geological Survey, in cooperation with the San Antonio Water System, during 2002-03. Helium analyses are used to provide insight into the sources of groundwater in the freshwater/saline-water transition zone of the San Antonio segment of...

We are in the midst of a continental-scale, multi-year experiment in the United States, in which we have not defined our testable hypotheses or set the duration and scope of the experiment, which poses major water-resources challenges for the 21st century. What are we doing? We are expanding population at...

Flood-frequency discharges were determined for 290 streamgage stations having a minimum of 9 years of record in West Virginia and surrounding states through the 2006 or 2007 water year. No trend was determined in the annual peaks used to calculate the flood-frequency discharges. Multiple and simple least-squares regression equations for the...

The ability of water-resource managers to adapt to future climatic change is especially challenging in coastal regions of the world. The East Coast of the United States falls into this category given the high number of people living along the Atlantic seaboard and the added strain on resources as populations...

New noble gas and radiogenic isotopic compositions are presented for tholeiitic, transitional, and alkalic rocks from the submarine Hilina region on the south flank of Kilauea, Hawaii. The 3He/4He ratios for undegassed glass and olivine separates (11–26 Ra) contrast with those of postshield and rejuvenated alkalic lavas, consistent with the alkalic...

This map and its accompanying dataset provide information for 51 natural occurrences of asbestos in Washington and Oregon, using descriptions found in the geologic literature. Data on location, mineralogy, geology, and relevant literature for each asbestos site are provided. Using the map and digital data in this report, the user...

The yield (or discharge) of constant-speed pumps varies with the total dynamic head (or lift) against which the pump is discharging. The variation in yield over the operating range of the pump may be substantial. In groundwater simulations that are used for management evaluations or other purposes, where predictive accuracy...

Summary 1. Habitats are often connected by fluxes of energy and nutrients across their boundaries. For example, headwater streams are linked to surrounding riparian vegetation through invertebrate and leaf litter inputs, and there is evidence that consumers in downstream habitats are subsidised by resources flowing from headwater systems....

Data collected for the U.S. Geological Survey National Water-Quality Assessment program from 1992-2001 were used to investigate the relations between nutrient concentrations and nutrient sources, hydrology, and basin characteristics. Regression models were developed to estimate annual flow-weighted concentrations of total nitrogen and total phosphorus using explanatory variables derived from currently...

Dam construction and its impact on downstream fluvial processes may substantially alter ambient bank stability, floodplain inundation patterns, and channel morphology. Most of the world's largest rivers have been dammed, which has prompted management efforts to mitigate dam effects. Three high dams (completed between 1953 and 1963) occur along the...

This geologic map is a cooperative effort of the U.S. Geological Survey (USGS), the Bureau of Land Management, the National Park Service, and the U.S. Forest Service to provide a geologic database for resource management officials and visitor information services. This map was produced in response to information needs related...

Concentrations of organic biomarkers and concentrations of phosphorus in soil cores can potentially be used as proxies for historic population densities of wading birds on tree islands in the Florida Everglades. This report focuses on establishing a link between the organic biomarker uric acid found in wading bird guano and...

Felsic volcanic rocks have long been considered a primary source of uranium for many kinds of uranium deposits, but volcanogenic uranium deposits themselves have generally not been important resources. Until the past few years, resource summaries for the United States or the world generally include volcanogenic in the broad category...

The Mississippi-Alabama shelf is bounded to the west by landforms associated with the Mississippi River Delta, to the north by the barrier-island systems of the Mississippi Alabama shoreline, and to the east by the Desoto Canyon. This portion of the northern Gulf of Mexico has been described as a slowly...

  Mechanistic models for predicting species’ distribution patterns present particular advantages and challenges relative to models developed from statistical correlations between distribution and climate. They can be especially useful for predicting the range of invasive species whose distribution has not yet reached...