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Rockfalls and debris avalanches from steep hillslopes in northern Vermont are a continuing hazard for motorists, mountain climbers, and hikers. Huge blocks of massive schist and gneiss can reach the valley floor intact, whereas others may trigger debris avalanches on their downward travel. Block movement is facilitated by major joints...

Recovery of the first nearly complete thoracopygon of the trilobite genus Dixiphopyge Brezinski from the Chouteau Formation of central Missouri aids in evaluating the paleoecology and taxonomic affinities of this genus. Dixiphopyge is an isopygous trilobite, suboval in outline, and possessing nine thoracic segments. At the apex of each axial...

Analysis of high resolution diversity data for Mississippian corals in the western interior United States yielded mild latitudinal diversity gradients despite the small geographic area covered by samples and a large influence on diversity patterns by geographic sampling intensity (sample bias). Three competing plate tectonic reconstructions were...

The tungstorhenate(V) heteropolyanion [W9ReO32]5- has been isolated as guanidinium and cesium salts from reaction of [ReO2(PPh3)(py)3]+ with sodium tungstate. Crystallographic analysis of black Cs5[W9ReO32]·3H2O [triclinic, P1 or P1̄; a = 10.194(1), b = 11.503(2), c = 9.682(1) Å; α = 100.55(1), β = 115.81(1), γ = 99.13(1)°; Z = 1], based on 3743 reflections, shows the anion to be isostructural with decatungstate,...

Many current theories of community function are based on the assumption that disturbances such as herbivory act to reduce the importance of neighbor interactions among plants. In this study, we examined the effects of herbivory (primarily by nutria, Myocastor coypus) on neighbor interactions between three dominant grasses in three coastal marsh...

A nested surface water monitoring network was designed and tested to measure variability in pesticide concentrations in the San Joaquin River and selected tributaries during the irrigation season. The network design an d sampling frequency necessary for determining the variability and distribution in pesticide concentrations were tested in a prototype...

Adult spring chinook salmon (Oncorhynchus tshawytscha) elaborate high plasma concentrations of testosterone during sexual maturation, and these levels of testosterone have been shown to reduce the salmonid immune response in vitro. Our search for the mechanism of testosterone's immunosuppressive action has led to the characterization of an androgen receptor in...

The Carboniferous succession along the Trans-Alaska Crustal Transect (TACT) corridor in the Atigun Gorge area of the central Brooks Range consists of the Kayak Shale (Kinderhookian) and the Lisburne Group (Kinderhookian through Chesterian). The Kayak Shale is at least 210 m thick; it is chiefly black, noncalcareous shale with several...

In July 1994, parts of central and southwestern Georgia, southeastern Alabama, and the western panhandle of Florida were devastated by floods resulting from rainfall produced by Tropical Storm Alberto. Entire communities were inundated by flood waters as numerous streams reached peak stages and discharges far greater than previous floods in...

Returns from drilling in unconsolidated cobble and sand aquifers commonly do not identify lithologic changes that may be meaningful for hydrogeologic investigations. Vertical resolution of saturated, Quaternary, coarse braided-stream deposits is significantly improved by interpreting natural gamma (G), epithermal neutron (N), and electromagnetically...

This field trip begins in Salt Lake City and makes a clockwise circuit of Great Salt Lake, with primary objectives to observe stratigraphie and geomorphic records of Lake Bonneville. Stops include Stansbury Island, Puddle Valley, gravel pits at Lakeside and the south end of the Hogup Mountains, several stops in...

We describe a 9 m2 drop net and removable walkways designed to quantify densities of small fishes in wetland habitats with low to moderate vegetation density. The method permits the collection of small, quantitative, discrete samples in ecologically sensitive areas by combining rapid net deployment from fixed sites with the carefully...

Pioneers named El Dorado, Kansas, in 1857 for the beauty of the site and the promise of future riches but not until 58 years later was black rather than mythical yellow gold discovered when the Stapleton No. 1 oil well came in on October 5, 1915. El Dorado's leaders were...

Seismic tomography based on P-wave travel times and improved earthquake locations provides further evidence for mantle-wide convective flow. The use of body waves makes it possible to resolve long, narrow structures in the lower mantle some of which can be followed to sites of present-day plate oonvergence at the Earth's...

Recent development of age-determination techniques for Florida manatees (Trichechus manatus latirostris) has permitted derivation of age-specific data on reproduction and survival of a sample of 1212 carcasses obtained throughout Florida from 1976–1991. Population viability analysis using these data projects a slightly negative growth rate (−0.003) and an unacceptably low probability...

We describe a method for using spatially referenced regressions of contaminant transport on watershed attributes (SPARROW) in regional water-quality assessment. The method is designed to reduce the problems of data interpretation caused by sparse sampling, network bias, and basin heterogeneity. The regression equation relates measured transport rates in streams to...

Pulses of slip velocity can propagate on a planar interface governed by a constant coefficient of friction, where the interface separates different elastic materials. Such pulses have been found in two-dimensional plane strain finite difference calculations of slip on a fault between elastic media with wave speeds differing by 20%....

Ice-sheet sourced Pleistocene turbidite systems of the Labrador Sea are different from non-glacially influenced systems in their facies distribution and depositional processes. Two large-scale sediment dispersal systems are juxtaposed, one mud-dominated and associated with the Northwest Atlantic Mid-Ocean Channel (NAMOC), the other sand-dominated and forming a huge submarine braided sandplain....

The U.S. Geological Survey (USGS) sampled stormwater in 16 cities and metropolitan areas that are required to obtain permits to discharge stormwater from their municipal storm-sewer system into surface water. Concentrations of 62 volatile organic compounds (VOCs), including methyl tert-butyl ether (MTBE) and BTEX (benzene, toluene, ethylbenzene, and total xylene)...

The origin and distribution of twelve potentially Hazardous Air Pollutants (HAPs; As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) identified in the 1990 Clean Air Act Amendments were examined in relation to the maceral composition of the A1 bed (Paleocene, Calvert Bluff Formation, Wilcox Group)...

Ice and ice-borne sediments were collected across the Arctic Basin during the Arctic Ocean Section, 1994 (AOS-94), a recent US/Canada trans- Arctic expedition. Sediments were analysed for 137Cs, clay mineralogy and carbon. Concentrations of 137Cs ranged from 5 to 73 Bq kg-1 in the ice- borne sediments. Concentrations of ice...

The Solitario is a large, combination laccolith and caldera (herein termed “laccocaldera”), with a 16-km-diameter dome over which developed a 6×2 km caldera. This laccocaldera underwent a complex sequence of predoming sill, laccolith, and dike intrusion and concurrent volcanism; doming with emplacement of a main laccolith; ash-flow eruption and caldera...

Massive/high velocity solar, galactic, and cosmic debris impacting the Earths surface may account for the enormous energy required for the formation of Permo-Carboniferous sedimentary basins and related mountain building orogenies. Analysis of satellite immagry, sea floor sonar, geophysical data, and geotectonic fabrics show a strong correlation throughout geologic time between...

Modern cone scales and seeds of Pinus strobus and Sequoia sempervirens, and their fossil (Upper Miocene, c. 6 Mar) counterparts Pinus leitzii and Sequoia langsdorfi have been studied using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), electron-microprobe and scanning electron microscopy. Microscopic observations revealed only minor microbial activity and high-quality structural preservation of...

The binding of pyrene to a number of humic substances isolated from various aquatic sources and a commercial humic acid was measured using the solubility enhancement method. The humic materials used in this study were characterized by various spectroscopic and liquid chromatography methods. A strong correlation was observed between the...