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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...

The Delaware Water Gap National Recreation Area (DEWA) contains a rich geologic and cultural history within its 68,714 acre boundary. Following the border between New Jersey and Pennsylvania, the Delaware River has cut a magnificent gorge through Kittatinny Mountain, the Delaware Water Gap, to which all other gaps in the...

40Ar/39Ar dating of muscovite, biotite, and K-feldspar combined with microstructural analysis of lower greenschist-facies, polymetamorphic, phyllitic rocks, and marbles were successfully used to decipher the thermal and tectonic histories of the Westminster and adjacent terranes in western Maryland. The presence of unreset detrital muscovite in some samples demonstrates that temperatures...

Plant communities of Unalaska Island in the eastern Aleutian Islands of western Alaska, and their relationship to environmental variables, were studied using a combined Braun-Blanquet and multivariate approach. Seventy relevés represented the range of structural and compositional variation in the matrix of vegetation and landform zonation. Eleven major community types...

The eastern central Front Range of the Rocky Mountains in Colorado has long been a region of geologic interest because of Laramide-age hydrothermal polymetallic vein-related ores. The region is characterized by a well-exposed array of geologic structures associated with ductile and brittle deformation, which record crustal strain over 1.7 billion...

A multi-institutional partnership, the US Agency for International Development’s Famine Early Warning System Network (FEWS NET) provides routine monitoring of climatic, agricultural, market, and socioeconomic conditions in over 20 countries. FEWS NET supports and informs disaster relief decisions that impact millions of people and involve billions of dollars. In this...

Sediment accretion is a critical indicator of initial progress in tidal marsh restoration. However, it is often difficult to measure early deposition rates, because the bottom surface is usually obscured under turbid, tidally-influenced waters. To accurately measure early sediment deposition in marshes, we developed an echosounder system consisting of a...

During the 1964 M9.2 great Alaskan earthquake, submarine-slope failures resulted in the generation of highly destructive tsunamis at Port Valdez, Alaska. A high-resolution, mini-sparker reflection profiler was used to image debris lobes, which we attribute to slope failures that occurred both during and prior to the 1964 megathrust event. In...

The Greater Natural Buttes tight natural gas field is an unconventional (continuous) accumulation in the Uinta Basin, Utah, that began production in the early 1950s from the Upper Cretaceous Mesaverde Group. Three years later, production was extended to the Eocene Wasatch Formation. With the exclusion of 1100 non-productive (“dry”) wells,...

Acoustic and electrical image logs in fractured granitic rocks penetrated by U.S. Navy well 58A-10, Coso Wash, in the eastern margin of the Coso geothermal field, California, were compared to evaluate their relative ability to characterize fractures and fault rock textures and to measure stress orientations from borehole failure. Electrical...

There is a need to provide agency leaders, elected officials, and the general public with summary information regarding the effects of large wildfires. Recently, the Wildland Fire Leadership Council (WFLC), which implements and coordinates National Fire Plan (NFP) and Federal Wildland Fire Management Policies adopted a strategy to monitor the...

No abstract available...

Ammocrypta clara Jordan and Meek (western sand darter) occurs primarily in the western portions of Mississippi River system, but also has been reported from a Lake Michigan drainage and a few eastern Texas Gulf Slope rivers. Additional range records depict a semi-disjunct distribution within the Ohio River drainage, including collections from...

Naturally occurring arsenic-contaminated groundwater is present within the Eastern Slate Belt (ESB) of North Carolina. Long-term, integrated geologic and geo-chemical investigations havedetermined the presence of arsenic by analyzing precipitates from first and second order streams under base flow conditions. When groundwater discharges into streams, arsenic and other metals are precipitated...