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The Baid al Jimalah tungsten deposit in Saudi Arabia (lat 25 degrees 09'N, long 42 degrees 41'E) consists predominantly of swarms of steeply dipping, subparallel, tungsten-bearing quartz veins and of less abundant, smaller stockwork veins. It is spatially, temporally, and genetically associated with a 569 Ma, highly differentiated, porphyritic, two-feldspar...

The sulfur geochemistry of the lacustrine Paleogene Green River Formation (Colorado, Utah, and Wyoming, USA) is unlike that of most marine and other lacustrine rocks. Distinctive chemical, isotopic, and mineralogical characteristics of the formation are pyrrhotite and marcasite, high contents of iron mineral sulfides strikingly enriched in34S, cyclical trends in...

Nitrogen inputs to, and outputs from, a 55-acre site in Lancaster County, Pennsylvania, were estimated to determine the pathways and relative magnitude of loads of nitrogen entering and leaving the site, and to compare the loads of nitrogen before and after the implementation of nutrient management. Inputs of nitrogen to...

No abstract available....

Geologic mapping, thermal inertia measurements, and an analysis of the color (visual wavelengths) of the martian volcano Apollinaris Patera indicate the existence of two different surface materials, comprising an early, easily eroded edifice, and a more recent, competent fan on the southern flank. A chronology of six major events that...

West Virginia is the only place in the United States where an entire section of Pennsylvanian age (Upper Carboniferous) strata can be seen. These strata occur within a wedge of rock that thins to the north and west from the southeastern...

We used geologic and geochemical techniques to document the change with time of the distribution and concentration of contaminated bottom sediments in southern Lake Champlain near an International Paper Company plant. Our work, initiated in 1972, was expanded on behalf of Vermont citizens in a class-action suit against the International...

Ammonium bound to silicate and sulfate minerals has recently been located at several major hydrothermal systems in the western U.S. utilizing newly-discovered near-infrared spectral properties. Knowledge of the origin and mineralogic relations of ammonium minerals at known hydrothermal systems is critical for the proper interpretation of remote sensing data and...

The explosion of a cryptodome at Mount St. Helens in 1980 produced two juvenile rock types that are derived from the same source magma. Their differences-color, texture and density-are due only to vesicularity differences. The vesicular gray dacite comprises bout 72% of the juvenile material; the black dacite comprises the...

Detailed sampling of the Vesuvius lavas erupted in the period A.D. 1631-1944 provides a suite of samples for comprehensive chemical analyses and related studies. Major elements (Si, Ti, Al, Fetotal, Mn, Mg, Ca, Na, K and P), volatile species (Cl, F, S, H2O+, H2O- and CO2), and ferrous iron (Fe2+)...

Crude oil spilled from a pipeline break in a remote area of north-central Minnesota has contaminated a shallow glacial outwash aquifer. Part of the oil was sprayed over a large area to the west of the pipeline and part of it accumulated...

We have undertaken U Th Pb, Sm Nd, Rb Sr, and 40Ar39Ar">40Ar39Ar isotopic studies on Asuka 881757, a coarse-grained basaltic lunar meteorite whose chemical composition is close to low-Ti and very low-Ti (VLT) mare basalts. The Pb Pb internal isochron obtained for acid leached residues of...

Four test fields in the south Dade agricultural area were studied to determine the effects of sludge application on ground-water quality. Two fields had been cultivated for 10 years or more, and two had not been farmed for at least 10 years. The fields were representative of the area's two...

Samples of ground water and soil gas were analyzed to study the occurrence of volatile and semivolatile organic compounds in the Memphis aquifer at Alamo in western Tennessee in 1989. At Alamo, the aquifer is locally unconfined. Four wells screened in the Memphis aquifer provided Alamo with 0.3 million gallons...

Communities in the lower Merrimack River basin and coastal river basins of southeastern New Hampshire are experiencing increased demands for water because of a rapid increase in population. The population in 1987 was 225,495 and is expected to increase by 30 percent during the next decade. As of 1987, five...

This report presents data collected from 202 wells between June 1987 and September 1990 as part of the Central Oklahoma aquifer pilot study of the National Water-Quality Assessment Program. The report describes the sampling networks, the sampling procedures, and the results of the ground-water quality and quality-assurance sample analyses. The...

Hydrologic data were collected from wells in the Salt Lake Valley, Utah, from 1990 to 1992, to better understand the hydrologic system in the valley. Most of the data collected are from 36 monitoring wells drilled in June and July 1990 and March and May 1991 using a hollow-stem auger....

Sixty-five wells were installed at 39 sites in the Arnold Air Force Base area in Coffee and Franklin Counties, Tennessee. The wells were installed to provide information on subsurface lithology, aquifer characteristics, ground-water levels, and ground-water quality. Well depths ranged from 11 to 384 feet. Water-quality samples were collected from 60...

No abstract available....

Nonhydrated obsidians are quenched magmatic liquids that record in their chemical compositions details of the tectonic environment of formation and of the differentiation mechanisms that affected their subsequent evolution. This study attempts to analyze, in terms of geologic processes, the compositional variations in the subalkalic silicic obsidians (Si02≥70 percent by...

The relative precision and accuracy of sampling and analysis methods for the determination of trace concentrations of volatile organic compounds (VOCs) in ground water were compared. Samples were collected from a well containing nanogram‐per‐liter (ng/L) to microgram‐per‐liter (μg/L) levels of VOCs. A Keck helical rotor submersible pump was used to...

Digital elevation data for the island of Hawaii from the U.S. Geographical Survey gridded at 30 m spacing was used to generate a slope map, a shaded relief map, and plots that compare slope and elevation for each of the five volcanoes that compose the island.These computer- generated products are...

A combined field and laboratory study was conducted to compare purge and trap gas chromatography/mass spectrometry (PT‐GC/MS) and purgeable organic chloride (POC1) analysis for measuring volatile chlorinated hydro‐carbons (VCH) in ground water. Distilled‐water spike and recovery experiments using 10 VCH indicate that at concentrations greater than...

A new method of collecting samples of unsaturated-zone water for quantitative analysis for a volatile organic compound, trichloroethene (TCE), was compared to three other, previously described sampling methodologies in the laboratory and in the field. In the laboratory, prepared water samples containing TCE in a known concentration (20 µg/L) were...

In the northwestern part of the San Juan basin, Colorado, thick high-volatile B bituminous coal deposits in the Upper Cretaceous Fruitland Formation are associated with nearshore marine sandstones of the Pictured Cliffs Sandstone. Detailed work along the outcrop and examination of...