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Using Viking Orbiter images, detailed photoclinometric profiles were obtained across 10 irregular depressions, 32 fretted fractures, 49 troughs and pits, 124 solitary scarps, and 370 simple grabens in the north Tharsis region of Mars. These data allow inferences to be made on the shallow crustal structure of this region. The...

Minimizing the loss of target organic chemicals from environmental water samples between the time of sample collection and isolation is important to the integrity of an investigation. During this sample holding time, there is a potential for analyte loss through volatilization from the water to the headspace, sorption to the...

Previous models of degassing, cooling and compaction of rhyolitic ash flow deposits are combined in a single computational model that runs on a personal computer. The model applies to a broader range of initial and boundary conditions than Riehle's earlier model, which did not integrate heat and mass flux with...

Ninety shallow monitoring wells on Long Island, N.Y., were used to test the hypothesis that the correlation between the detection of volatile organic compounds (VOC's) at a well and explanatory variables representing land use, population density, and hydrogeologic conditions around the well is affected by the size and shape of...

Volatile dimethylselenide (DMSe) was transformed to a nonvolatile Se compound in a ??-MnO2 suspension. The nonvolatile product was a single compound identified as dimethylselenoxide based on its mass spectra pattern. After 24 h, 100% of the DMSe added to a ??-MnO2 suspension was converted to nonpurgable Se as opposed to...

Mantle helium in continental environments is generally considered to be the result of active volcanism and/or active extension. The latest episodes of volcanism in northeastern North America are the track of the New England hotspot (95–190 Ma) and the closure of the Iapetus sea (before 300 Ma). Thus, the identification...

Methyl bromide (MeBr) is used extensively in agriculture as a soil fumigant and there is growing concern over the role it may play in the depletion of stratospheric ozone. Methyl bromide is applied using various techniques and very little is known about how much of the...

A method has been developed to measure nanogram per liter amounts of selected volatile organic compounds (VOCs) including dichlorodifluoromethane, trichlorofluoromethane, cis-1,2-dichloroethene, trichloroethene, tetrachloroethene, and the isomers of dichlorobenzene in water. The method uses purge-and-trap techniques on a 100 mL sample, gas chromatography with a megabore capillary column, and electron impact,...

The objective of this study was to investigate the occurrence of herbicide active and inactive ingredients (primarily volatile organic compounds) at four selected sites in Iowa representing drain tiles, observation wells, or lysimeters. Water samples were collected monthly and bi-monthly before and after herbicide applications in 1991, respectively. They...

Two coal zones, the San Pedro and the overlying Santo Tomas, are present for nearly 35 km in outcrop, surface and underground mines, and shallow drill holes along the strike of the middle part of the Claiborne Group (Eocene) in Webb County, Texas. A sandstone-dominated interval of 25 to 35...

Data on the quantity and quality of ground water that drains into dry docks at the Puget Sound Naval Shipyard can be useful for planning environmental remediation work at the shipyard. Ground-water discharges into and total drain-water discharges from individual dry docks were computed from a single set of discharges...

No abstract available....

Selected reaches of Grant Line Arroyo and Tijeras Arroyo in Albuquerque, New Mexico, were studied to collect information about the amount and quality of infiltration through arroyo channels. Infiltration rate was calculated for selected reaches of Grant Line Arroyo and Tijeras Arroyo based on instantaneous streamflow-loss volumes, wetted channel area, and instantaneous...

A recent study by the U.S. Geological Survey (USGS) under the National Water-Quality Assessment (NAWQA) program characterized the ground-water quality in a part of the Denver, Colorado, metropolitan area. The study provides an assessment of water-quality conditions in an alluvial aquifer that drains into the South Platte River. Thirty wells...

Sediments of the upper Clark Fork River, from the Butte and Anaconda area to Milltown Reservoir (230 km downstream), are contaminated with As, Cd, Cu, Pb, Mn, and Zn primarily from mining activities. The toxicity of pore water from these sediments was determined using Daphnia magna (48-h exposure), rainbow trout (96-h...

A study of the South Prong of Spavinaw Creek Basin conducted baween July 14 and July 23. 1993. described the surface- and ground-water quality of the basin and the streamflow gain and loss. Water samples were collected from 10 sites on the mainstem of the South Prong of Spavinaw Creek...

The 187-square mile study area is in the Triassic-Jurassic Newark Basin. Most of the area is underlain by sedimentary rocks of Upper Triassic age (74 percent) and intrusive diabase of Jurassic age (12 percent) and includes two southwest-northeast trending valleys underlain by carbonate and crystalline rock. Ground water in the sedimentary...

Hydrologic, water-quality, and meteorologic data were collected from January 1993 through March 1994 as part of a water-quality investigation of the Upper Catawba River Basin, North Carolina. Specific objectives of the investigation were to characterize the water quality of Rhodhiss Lake, Lake Hickory, and three tributary streams, and to calibrate...

Rainfall, streamflow, and water-quality data were collected furing storm conditions at five urban watersheds in Nashville, Tennessee. These data can be used to build a database for developing predictive models of the relations between storm- water quality and land use, storm characteristics, and seasonal variations. The primary land and mix...

A study of the Yocum Creek Basin conducted between July 27 and August 3, 1993, described the surface- and ground-water quality of the basin and the streamflow gain and loss. Water samples were collected from 12 sites on the main stem of Yocum Creek and 2 tributaries during periods...

Hydrologic and water-quality data were collected in northern Bucks County, Pa., as part of a study conducted by the U.S. Geological Survey, in cooperation with Bridgeton, Buckingham, Nockamixon, Plumstead, Solebury, Springfield, Tinicum, and Wrightstown Townships and New Hope Borough. Hydrologic data on ground water and surface water were collected to...

Mean annual base-flow and stormflow yields of selected water-quality constituents from urban watersheds of Jefferson County, Kentucky, were estimated for 1988-92 to help describe the pro portions of constituent transport from point and nonpoint sources. Yield estimates were based on streamflow and water-quality data collected from a network of 25...

Vadnais Lake is located in northern Ramsey County, Minnesota. The lake is managed by the St. Paul Water Utility for storage of municipal water supplies that are provided to residents of St. Paul and surrounding communities. In recent years, algal blooms in Vadnais Lake have caused taste and odor problems...

A zone of contaminated ground water at Picatinny Arsenal has resulted from the operation of a metal- plating facility in building 95 during 1960-81, and the wastewater-treatment system that is in and adjacent to the building. Thirty-two monitoring wells were installed in 1989 to supplement 12 previously installed wells. All...