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Trace levels of chalcophile elements that form volatile sulfide minerals are determined in stream sediments and in the nonmagnetic fraction of a heavy-mineral concentrate of stream sediments by a carrier distillation emission spectrographic method. Photographically recorded spectra of samples are visually...

Analysis of water-level fluctuations in about 30 observation wells and 5 lakes in the Crescent Lake National Wildlife Refuge in the sandhills of Nebraska indicates water-table configuration beneath sand dunes in this area varies considerably, depending on the configuration of the topography of the dunes. If the topography of an...

The effects of acid deposition on surface waters in eastern United States watersheds having similar size, physiography, climate and land use are related to the composition of the underlying bedrock. Watersheds developed on greenstone, calcareous shale, sandstone, granite, and schist differ in their ability to neutralize acid deposition....

Concentrations of U, Th and Pb, and the isotopic composition of Pb for whole-rock samples of granitoids show: (1) that open-system behavior is nearly universal in the surface and near-surface environment; and (2) that elemental mobility is possible to depths of several hundred meters. Several identified or at least postulated...

In decades past, the rancher depended upon reports from cowboys to gather information he needed to make management decisions. Today, the vast open ranges of the cowboy era are mostly gone in the United States-fenced into pastures, paddocks, or fields that are now discrete management units. But fencing in the...

In June 1984, fry of Atlantic salmon, Salmo salar L., (0-3 g mean weight), being reared in a hatehery operated by the University of Washington, began to die and infectious haematopoietic necrosis (IHN) was diagnosed. A total of 40 000 fry were being held in 11 tanks. Mortality due to...

The Clarno Formation, a mostly Eocene and partly early Oligocene sequence of andesitic lavas and volcaniclastic rocks, is the oldest Tertiary formation exposed in north central Oregon. Remanent magnetization directions at 46 sites in the lavas provide a paleomagnetic pole at 84°N, 278°E with a 95% confidence cone of 7°....

No abstract available....

Temperature surveys at depths of 1–2 m have had varying success in geothermal exploration in the Basin and Range province. The most successful surveys have identified patterns of near-surface thermal-fluid flow within areas of less than 2 km2. Results have been less consistent in larger areas where zones of hydrothermal...

Numerical modeling techniques are used to examine the hydrogeologic, design, and management factors governing the recovery efficiency of subsurface fresh-water storage. The modeling approach permitted many combinations of conditions to be studied. A sensitivity analysis was used that consisted of varying certain parameters while keeping constant as many other parameters...

The precipitous decline in abundance of walleyes (Stizostedion vitreum vitreum) in western Lake Erie during the 1960s caused major concerns for the future of this resource. Mercury contamination in walleyes in 1970 resulted in a moratorium on commercial fishing in United States and Canadian waters. The opportunity arose for resource...

Lake trout were collected in graded-mesh gill nets and forage fishes were collected in trawls in mid December 1981 and late March 1982. The length ranges of 317 lake trout caught in December and 138 in March were 280–767 and 286–857...

Adult forms of the cladoceran Bythotrephes cederstroemi Schoedler (Cercopagidae), a widespread European freshwater zooplankter, occurred in the stomachs of four common species of Lake Erie fish (yellow perch, Perca flavescens; white perch, Morone americana; white bass, M. chrysops; and walleye, Stizostedion vitreum vitreum) collected in early October 1985. The fish were collected at several stations in...

An extensive survey was conducted in fall 1978 to determine the distribution and abundance of submersed macrophytes through the St. Clair-Detroit River system from Lake Huron to Lake Erie. Submersed macrophytes, representing 19 taxa, were widely distributed in the system, being found on 358 km2 (30%) of the total 1185 km2 of...

No abstract available ...

The first two months of the year were somewhat quiet seismically speaking. There were no major earthquakes (7.0-7.9) but one death was caused by an earthquake in Peru. In the United States a magntidue 4.9 earthquake in Ohio on January 31 caused some minor injuries and was felt in eleven states,...

Saltwater intrusion is particularly dynamic in coastal Dade County because of the high permeability of the Biscayne aquifer, because of the good interconnection between canals and the aquifer, and because of the seasonal rainfall. The problem is accentuated as urban growth continues to encroach on inland wetland areas which results...

No abstract available....

No abstract available....

Paleomagnetic and rock magnetic data combined with stable isotope data from the middle Tertiary pluton along the Rio Hondo in northern New Mexico suggest that its magnetic remanence has both thermal (TRM) and high-temperature chemical (CRM) components. Oxygen isotope temperatures indicate...

No abstract available. ...

Nitellopsis obtusa, a macroalga (Characeae) native to Europe and Asia, was found in U.S. waters of the St. Clair-Detroit River system in 1983, thus extending the range of this taxon into the Laurentian Great Lakes about 850 km from the St. Lawrence River where it was first discovered...

No abstract available....