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Analysis of continuous GPS observations between 1996 and 2000 at 62 stations distributed throughout the central and eastern United States suggests that the area is generally stable. Seven of the 62 stations show anomalous velocities, but there is reason to suspect their monument stability. Assuming the remaining 55 stations are...

Part of an annual review of mines and mineral resources in the U.S. An overview of nonfuel-mineral exploration in 2000 is presented. Principal exploration target was gold exploration in Latin America, Australia, and the U.S. There was a decrease of 18 percent in the exploration budget for gold as compared...

A torrential rainstorm on September 1, 1994 at the recently burned hillslopes of Storm King Mountain, CO, resulted in the generation of debris flows from every burned drainage basin. Maps (1:5000 scale) of bedrock and surficial materials and of the debris-flow paths, coupled with a 10-m Digital Elevation Model (DEM)...

Mosses and lichens are important components of boreal landscapes [Vitt et al., 1994; Bubier et al., 1997]. They affect plant productivity and belowground carbon sequestration and alter the surface runoff and energy balance. We report the use of multiresolution satellite data to map moss and lichens over the BOREAS region...

Food habits of swift foxes (Vulpes velox) occupying two distinct landscapes (dominated by cropland versus rangeland) in western Kansas were determined by analysis of scats collected in 1993 and 1996. Frequencies of occurrence of prey items in scats were compared between cropland and rangeland areas by season. Overall, the most...

Although considerable uncertainty and disagreement prevail concerning the world's gas-hydrate resources, the estimated amount of gas in those gas-hydrate accumulations greatly exceeds the volume of known conventional gas reserves. However, the role that gas hydrates will play in contributing to the world's energy requirements will ultimately depend less on the...

In the present work a combined analytical method involving toxicity and liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) was developed for the determination of pharmaceutical compounds in water samples. The drugs investigated were the analgesics: ibuprofen, ketoprofen, naproxen, and diclofenac, the decomposition product of the acetyl salicylic acid: salicylic acid and one...

Two Aeromonas salmonicida-specific polymerase chain reaction (PCR) tests and 1 A. salmonicida subsp. salmonicida-specific PCR test were used to screen salmonid populations that were either overtly or covertly infected with A. salmonicida subsp. salmonicida. It was demonstrated that these PCR assays could be used to replace the biochemical testing currently employed to confirm the identity of A. salmonicida isolates...

The concentration and distribution of inorganic Hg was measured using cold-vapor atomic fluorescence spectrometry in samples collected at selected sites on the Sacramento River from below Shasta Dam to Freeport, CA, at six separate times between 1996 and 1997. Dissolved (ultrafiltered, 0.005 μm equivalent pore size) Hg concentrations remained...

A house exploded in the City of Kingsford, Michigan USA. The explosion was caused by CH4 that leaked into the basement from the surrounding soil. Evidence suggests that biodegradation of products from the distillation and spillage at or near a former wood carbonization plant site was the major source of...

Birds can accurately navigate over hundreds to thousands of kilometres, and use celestial and magnetic compass senses to orient their flight. How birds determine their location in order to select the correct homeward bearing (map sense) remains controversial, and has been attributed to their olfactory or magnetic senses. Pigeons can...

Parasitism of the leafhopper Sophonia rufofascia (Kuoh and Kuoh), a recent immigrant that has become a widespread pest in Hawaii, was examined in a 1-year survey in Hawaii Volcanoes National Park. Samples of young leaves of four plant species infested with eggs of S. rufofascia were collected at five sites...

The model presented here simulates a network of parallel and sequential reactions that describe the structural and chemical transformation of lignin-derived sedimentary organic matter (SOM) and the resulting generation of mobile species from shallow burial to approximately low-volatile bituminous rank. The model is calibrated to the Upper Cretaceous Williams Fork...

Molecular-level condensed tannin analyses were conducted on a series of mangrove (Rhizophora mangle) leaves at various stages of decomposition in a tropical estuary. Total molecular tannin yields ranged from 0.5% ash-free dry weight (AFDW) in the most highly degraded black leaves (6-7 weeks in the water) up to >7% AFDW...

Differential rates of plagioclase and K-feldspar weathering commonly observed in bedrock and soil environments are examined in terms of chemical kinetic and solubility controls and hydrologic permeability. For the Panola regolith, in the Georgia Piedmont Province of southeastern United States, petrographic observations, coupled with elemental balances and 87Sr/86Sr ratios, indicate...

An extensive (~ 25 km2) landslide complex covers a large area on the west side of the Williams Fork Mountains in central Colorado. The complex is deeply weathered and incised, and in most places geomorphic evidence of sliding (breakaways, hummocky topography, transverse ridges, and lobate distal zones) are no longer...

This study examined trace elements concentrations and macroinvertebrate community structure at 32 sites in 22 streams in Colorado. Sites affected by mining activities (mining sites) and sites that were minimally disturbed (nonmining sites) were selected for the assessment. Water and transplanted aquatic bryophyte samples were analyzed for trace elements. Macroinvertebrate...

Geophysical time series often contain missing data, which prevents analysis with many signal processing and multivariate tools. A modification of singular spectrum analysis for time series with missing data is developed and successfully tested with synthetic and actual incomplete time series of suspended-sediment concentration from San Francisco Bay. This method...

Rock avalanches, debris flows, and related phenomena consist of grain-fluid mixtures that move across three-dimensional terrain. In all these phenomena the same basic forces, govern motion, but differing mixture compositions, initial conditions, and boundary conditions yield varied dynamics and deposits. To predict motion of diverse grain-fluid masses from initiation to...

To understand the role of the world's coastal zone (CZ) in global biogeochemical fluxes (particularly those of carbon, nitrogen, phosphorus, and sediments) we must generalise from a limited number of observations associated with a few well-studied coastal systems to the global scale. Global generalisation must be based on globally available...

An updated version of the catalog that was used for the current national probabilistic seismic-hazard maps would suffice for production of large-scale hazard maps of the Memphis urban area. Deaggregation maps provide guidance as to the area that a catalog for calculating Memphis hazard should cover. For the future, the...

Air samples collected on St. John in the U.S. Virgin Islands were screened for the presence of viable bacteria and fungi to determine if the number of cultivatable microbes in the atmosphere differed between "clear atmospheric conditions" and "African dust-events." Results indicate that during "African dust-events," the numbers of cultivatable...

Major, trace element and isotopic (Sr, Nd, Pb) data are reported for representative samples of interplinian (Protohistoric, Ancient Historic and Medieval Formations) activity of Mt. Somma-Vesuvius volcano during the last 3500 years. Tephra and lavas exhibit significant major, trace element and isotopic variations. Integration of these data with those obtained...

Yucca Mountain, located in southern Nevada in the Mojave Desert, is being considered as a geologic repository for high-level radioactive waste. Although the site is arid, previous studies indicate net infiltration rates of 5-10 mm yr-1 under current climate conditions. Unsaturated flow of water through the mountain generally is vertical...

Paleomagnetic and structural data from intermediate to mafic composition lava flows and related dikes in all major blocks of the late Miocene Hamblin-Cleopatra Volcano, which was structurally dismembered during the development of the Lake Mead Fault System (LMFS), provide limits on the magnitude and sense of tilting and vertical axis...