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Lake Tahoe was surveyed using a state-of-the-art, high-resolution, multibeam mapping system to provide an accurate base map for the myriad of ongoing environmental studies in and around the lake. The newly defined basin morphology shows steep basin margins on the northern, eastern, and western sides and a gentle margin on...

Salinity oscillations caused by multidecadal climatic variability had major impacts on the Chesapeake Bay estuarine ecosystem during the past 1000 yr. Microfossils from sediments dated by radiometry (14C, 137Cs, 210Pb) and pollen stratigraphy indicate that salinity in mesohaline regions oscillated 10-15 ppt during periods of extreme drought (low fresh-water discharge)...

The Okefenokee Swamp is a 160,000 ha freshwater wetland in Southeast Georgia, USA that developed in a landscape basin. Hydrologic variability across the swamp suggests that water-surface elevations are not uniform across the swamp. The topographic surface map discussed herein was developed to describe the swamp topography at local to...

Concentrations of naturally occurring arsenic in ground water vary regionally due to a combination of climate and geology. Although slightly less than half of 30,000 arsenic analyses of ground water in the United States were 1 μg/L, about 10% exceeded 10 μg/L....

The introduced tree Sapium sebiferum (Euphorbiaceae) is considered a serious threat to the preservation of the coastal prairie region of Louisiana and Texas, although it is currently uncommon in the western part of the region. The objective of this study was to evaluate the potential effects of location, soils, and...

Magnetotelluric traverses across the southern Yukon-Tanana terrane (YTT) reveal the presence of a thick conductive layer (or layers) beneath Paleozoic crystalline rocks. These rocks have been interpreted to be flysch of probable Mesozoic age, on the basis of the occurrence of Jurassic-Cretaceous flysch in the Kahiltna assemblage and Gravina-Nutzotin belt...

The changes of the solid Earth in south central Alaska in response to two major glacial fluctuations on different temporal and spatial scales have been estimated and we evaluated their influence on the stress state and ongoing tectonic deformation of the region. During the recent (1993–1995) Bering Glacier surge, a...

Conventional reservoir quality data for more than 300 wells provided by the Illinois and Indiana state geological surveys were analyzed to determine the factors governing porosity and permeability in the Upper Mississippian Aux Vases Sandstone, an important hydrocarbon-producing unit in the Illinois Basin. In addition, approximately 150 samples of the...

The surface morphology of the northern slope of the Brooks Range (North Slope) from the Canning River, Alaska, eastward is dominated by a series of large alluvial fans and braided streams floored by coarse alluvium. On the basis of our studies, we conclude that the fans are not prograding now...

Water resources data for the 1999 water year for New York consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and ground-water levels. This volume contains records for water discharge at 137 gaging stations; stage only at 11 gaging...

The Palisade 1:24,000 quadrangle is in Mesa County in western Colorado. Because the map area is dominated by various surficial deposits, the map depicts 22 different Quaternary units. Two prominent river terraces are present in the quadrangle containing gravels deposited by the Colorado River. The map area contains many mass...

Fish community data were collected by the U.S. Geological Survey (USGS) at 12 sites in 1996 in the Wapsipinicon, the Cedar, the Iowa, and the Skunk River Basins in eastern Iowa. The study was done as part of the National Water-Quality Assessment (NAWQA) Program of the USGS. This report presents an...

The Pheasant Branch watershed in Dane County is expected to undergo development. There are concerns that this development will adversely affect water resources, including Frederick Springs, a large spring complex in the watershed. The spring's recharge area was delineated using a telescopic mesh refinement (TMR) model constructed from an existing...

The cities of Kingsford and Iron Mountain are in the southwestern part of Dickinson County in the Upper Peninsula of Michigan. Residents and businesses in these cites rely primarily on ground water from aquifers in glacial deposits. Glacial deposits generally consist of an upper terrace sand-and-gravel unit and a lower...

The statewide average precipitation of 36.00 inches for the 1999 water year was 4.35 inches greater than the normal annual precipitation of 31.65 inches for water years 1961-90. Average precipitation values ranged from 83 percent of normal at both the Rosholt 9 NNE weather station in north central Wisconsin and...

The Ninth Woodcock Symposium was held January 26-28, 1997 in Baton Rough, Louisiana. Contents include: American Woodcock Management, Past, Present, and Future; Current Population Status and Likely Future Trends for American Woodcock; American Woodcock Use of Reclaimed Surface Mines in West Virginia; Food Habits and Preferences of American Woodcock in...

No abstract available....

The Cockfield and lower Wilcox aquifers are sources of water for local use in southern and northeastern Arkansas, where in 1995 more than 51 million gallons per day of water was withdrawn. During January through April 2000, 54 water-level measurements were made in wells completed in the Cockfield aquifer, 13...

Multiple and simple least-squares regression models for the log10-transformed 100-year discharge with independent variables describing the basin characteristics (log10-transformed and untransformed) for 267 streamflow-gaging stations were evaluated, and the regression residuals were plotted as areal distributions that defined three regions of the State, designated East, North, and South. Exploratory data...

No abstract available....

The Sangre de Cristo Mountains of south-central Colorado and north-central New Mexico are the physiographic expression of a southerly trending Cenozoic structural uplift that plunges gently south to die out in the Great Plains south of Santa Fe and Las Vegas, New Mexico. The uplift is bounded on the west...

The first large-scale, co-operative, studies of marked birds in North America were attempted in the 1950s. Operation Recovery, which linked numerous ringing stations along the east coast in a study of autumn migration of passerines, and the Preseason Duck Ringing Programme in prairie states and provinces, conclusively demonstrated the...

Historically the Swallow-tailed Kite (Elanoides forficatus) bred in the United States in at least 16 eastern states. Currently it is restricted to seven southeastern states, with most of its breeding range in Florida. Breeding Bird Surveys indicate a declining trend for this Neotropical migrant in most of Florida....

In response to a request from FUNDAECO, a Guatemalan non-government organization, we worked with them to develop a conservation strategy for the Cerro San Gil Protected Area and surrounding private lands. Volunteer banders from a dozen states and Canadian provinces assisted in long-term monitoring of populations of resident and migratory...

Upheaval Dome, in Canyonlands National Park, Utah, USA, is a unique structure on the Colorado Plateau. It has earlier been interpreted as an impact structure or as a pinched-off salt diapir. Some subrounded quartzose fragments were found in a ring depression near the eastern margin of the structure and, based...