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Land-surface subsidence and erosion are the principal processes that form accommodation space in interior coastal wetlands when they are converted to open water. The relative contribution of subsidence and erosion to wetland loss can be estimated by comparing elevations and vertical offsets of stratigraphic contacts that are correlated between adjacent...

Coastal flats worldwide that are periodically exposed to arid climates and periodically flooded by marine waters are unique depositional environments because they receive sediments surficially and interstitially from both land and sea.  The wind-tidal flats bordering Laguna Madre, Texas, which fit this unique category, are modified by eolian processes...

We characterize the textural and geochemical features of ocean crustal zircon recovered from plagiogranite, evolved gabbro, and metamorphosed ultramafic host-rocks collected along present-day slow and ultraslow spreading mid-ocean ridges (MORs). The geochemistry of 267 zircon grains was measured by sensitive high-resolution ion microprobe-reverse geometry at the USGS-Stanford Ion Microprobe facility....

This report presents the results of a contaminant monitoring survey conducted annually by the Missouri Department of Conservation to examine the levels of selected elemental contaminants in fish fillets, fish muscle plugs, and crayfish. Fillets of channel catfish (Ictalurus punctatus), bass (Micropterus salmoides, Micropterus dolomieu, Morone chrysops), walleye (Sander vitreus),...

Since late 1993, Metro Wastewater Reclamation District of Denver (Metro District), a large wastewater treatment plant in Denver, Colo., has applied Grade I, Class B biosolids to about 52,000 acres of nonirrigated farmland and rangeland near Deer Trail, Colo. (U.S.A.). In cooperation with the Metro District in 1993, the U.S....

This map summarizes the geology of the St. Joe 7.5-minute quadrangle in the Ozark Plateaus region of northern Arkansas. Geologically, the area lies on the southern flank of the Ozark dome, an uplift that exposes oldest rocks at its center in Missouri. Physiographically, the St. Joe quadrangle lies within the...

Mars Transverse Mercator (MTM) -20012 and -25012 quadrangles (lat 17.5 deg - 27.5 deg S., long 345 deg - 350 deg E.) cover a portion of Margaritifer Terra near the east end of Valles Marineris. The map area consists of a diverse assemblage of geologic surfaces including isolated knobs of...

In April and July of 1981, the U.S. Geological Survey (USGS) conducted geophysical surveys to investigate the shallow geologic framework of the Alabama-Mississippi-Louisiana Shelf in the northern Gulf of Mexico. Work was conducted onboard the Texas A&M University R/V Carancahua and the R/V Gyre to develop a geologic understanding of...

The U.S. Geological Survey (USGS) has collected streamflow information for the Nation's streams since 1889. Streamflow information is used to predict floods, manage and allocate water resources, design engineering structures, compute water-quality loads, and operate water-control structures. The current (2007) size of the USGS streamgaging network is over 7,400 streamgages...

From its origin in rugged granitic highlands of the central Brooks Range, the Noatak River flows westward between the De Long Mountains and the Baird Mountains before turning south to enter Kotzebue Sound. Glaciers of middle and late Pleistocene age entered the Noatak River valley from the east, north, and...

This report presents estimated daily and cumulative loads of suspended sediment and selected trace elements transported during water year 2008 at three streamflow-gaging stations that bracket the Milltown Reservoir project area in the upper Clark Fork basin of western Montana. Milltown Reservoir is a National Priorities List Superfund site where...

The Niobe Planitia quadrangle (V-23) encompasses approximately 8,000,000 km2 of the Venusian equatorial region extending from lat 0 deg to 25 deg N. and from long 90 deg to 120 deg E. (approximately 9,500 15-minute quadrangles on Earth). The map area lies along the north margin of the equatorial highland,...

The Phosphoria Sea extended at least 500 km westward and at least 700 km southwestward from its core area centered in southeastern Idaho. Throughout that extent it displayed many characteristic features of the core: the same fauna, the same unique sedimentary assemblage including phosphate in mostly pelletal form, chert composed...

Testing and specification of seismic and earthquake-engineering sensors and recorders has been marked by significant variations in procedures and selected parameters. These variations cause difficulty in comparing such specifications and test results. In July 1989, and again in May 2005, the U.S. Geological Survey hosted international public/private workshops with the goal...

The U.S. Geological Survey collects ground-water data and conducts studies to monitor hydrologic conditions, better define ground-water resources, and address problems related to water supply, water use, and water quality. Water levels were monitored continuously, in Georgia, in a network of 184 wells during 2006 and 182 wells during 2007....

Department of the Interior (DOI) bureaus have invested heavily (for example, the U.S. Bureau of Land Management (BLM) spent more than $60 million in fiscal year 2007) in seeding vegetation for emergency stabilization and burned area rehabilitation of non-forested arid lands over the past 10 years. The primary objectives of...

The Santa Ana River (SAR) in southern California is impacted by effluents from wastewater treatment plants (WWTP), which are sources of organic wastewater compounds (OWCs) and urban runoff. The Santa Ana River is one of only three river basins supporting native populations of the federally listed Santa Ana sucker (Catostomus...

Geographic information system (GIS) technology has become an important tool for scientific investigation, resource management, and environmental planning. A GIS is a computer-aided system capable of collecting, storing, analyzing, and displaying spatially referenced digital data. GIS technology is useful for analyzing a wide variety of spatial data. Remote sensing involves...

In June of 1990 and July of 1991, the U.S. Geological Survey (USGS) conducted geophysical surveys to investigate the shallow geologic framework of the Mississippi-Alabama-Florida shelf in the northern Gulf of Mexico, from Mississippi Sound to the Florida Panhandle. Work was done onboard the Mississippi Mineral Resources Institute R/V Kit...

Analysis of flow, temperature, and specific-conductance logs and depth-dependent water-quality samples collected under ambient and pumped conditions provided a preliminary delineation of flow zones and water quality in three deep abandoned water-supply wells. The integrated analysis was completed as part of the characterization of a fractured-sandstone aquifer in the mountainous...

The rocks and landforms of the Estes Park 30 x 60 minute quadrangle display an exceptionally complete record of geologic history in the northern Front Range of Colorado. The Proterozoic basement rocks exposed in the core of the range preserve evidence of Paleoproterozoic marine sedimentation, volcanism, and regional soft-sediment deformation,...

The U.S. Geological Survey (USGS), in cooperation with the Houston-Galveston Area Council and the Texas Commission on Environmental Quality, collected water-quality, stream-habitat, and biological data from two sites at West Fork Double Bayou, two sites at Cotton Bayou, and one site at Hackberry Gully in Chambers County, Texas, during July...

The U.S. Geological Survey is assessing groundwater availability in the Lake Michigan Basin. As part of the assessment, a variable-density groundwater-flow model is being developed to simulate the effects of groundwater use on water availability throughout the basin. The hydrogeologic framework for the Lake Michigan Basin model was developed by...

The survival of hatchery-origin juvenile coho salmon from the Trinity River Hatchery was estimated as they migrated seaward through the Trinity and Klamath Rivers. The purpose of the study was to collect data for comparison to a similar study in the Klamath River and provide data to the Trinity River...

The Volcano Hazards Program of the U.S. Geological Survey (USGS) is part of the Geologic Hazards Assessments subactivity as funded by Congressional appropriation. Investigations are carried out in the Geology and Hydrology Disciplines of the USGS and with cooperators at the Alaska Division of Geological and Geophysical Surveys, University of...