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Two recent large earthquakes in the Mojave Desert, California - the magnitude 7.3 1992 Landers and magnitude 7.1 1999 Hector Mine earthquakes - have each been followed by elevated crustal strain rates over periods of months and years. Geodetic data collected after the Hector Mine earthquake exhibit a temporally decaying...

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...

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...

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...

A main degradation product of Irgarol [2-(methylthio)-4-(tert-butylamino)-6-(cyclopropylamino)-s-triazine], one of the most widely used compounds in antifouling paints, was detected at trace levels in seawater and sediment samples collected from several marinas on the Mediterranean coast. This degradation product was identified as 2-methylthio-4-tert-butylamino-s-triazine. The unequivocal identification of this compound in seawater...

A list of freshwater fishes is presented for Acadia National Park, Mount Desert Island, Maine, based on past survey records, published and unpublished reports, and recent comprehensive surveys within or bordering Park boundaries conducted in 1998 and 1999. Overall, 31 species of fishes have been recorded in freshwaters of the...

A new high-pressure phase of methane hydrate has been identified based on its high optical relief, distinct pressure-temperature phase relations, and Raman spectra. In-situ optical observations were made in a hydrothermal diamond-anvil cell at temperatures between -40?? and 60 ??C and at pressures up to 900 MPa. Two new invariant...

Coalbed gases in the Lower Silesian Coal Basin (LSCB) of Poland are highly variable in both their molecular and stable isotope compositions. Geochemical indices and stable isotope ratios vary within the following ranges: hydrocarbon (CHC) index CHC = CH4/(C2H6+C3H8) from 1.1 to 5825, wet gas (C2+) index C2+ = (C2H6+...

The middle Pliocene warm period represents a unique time slice in which to model and understand climatic processes operating under a warm climatic regime. Palaeoclimatic model simulations, focussed on the United States of America (USA), for the middle Pliocene (ca 3 Ma) were generated using the USGS PRISM2 2?? ??...

We examined nesting success and levels of nest predation and cowbird parasitism among five different silvicultural treatments: regenerating (3-6 years old), mid-rotation (12-15 years old), and thinned (17-23 years old) pine plantations, single-tree selection, and late-rotation pine-hardwood stands in the Ouachita Mountains of Arkansas from 1993 to 1995. We monitored...

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...

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...

Meteoritical Bulletin No. 85 lists information for 1376 newly classified meteorites, comprising 658 from Antarctica, 409 from Africa, 265 from Asia (262 of which are from Oman), 31 from North America, 7 from South America, 3 from Australia, and 3 from Europe. Information is provided for 11 falls (Dergaon, Dunbogan,...

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...

Electrocution on power lines is one of many human-caused mortality factors that affect raptors. Cost-effective and relatively simple raptor-safe standards for power line modification and construction have been available for over 25 years. During the 1970s and early 1980s, electric industry efforts to reduce raptor electrocutions were very coordinated and...

We model the basin configuration beneath Las Vegas Valley, Nevada, on the basis of gravity, drillhole, and seismic reflection data. We locate and characterize the various strands of the Las Vegas Valley Shear Zone (LVVSZ) by variations in basin thickness beneath the valley. The pre-Tertiary bedrock surface is complex, with...

The processes responsible for hotspot seamount formation are complex, yet the cumulative frequency-volume distribution of hotspot seamounts in the Easter Island/Salas y Gomez Chain (ESC) is found to be well-described by an upper-truncated power law. We develop a model for hotspot seamount formation where uniform energy input produces events initiated...

A pore network model with cubic chambers and rectangular tubes was used to estimate the nonaqueous phase liquid (NAPL) dissolution rate coefficient, Kdissai, and NAPL/water total specific interfacial area, ai. Kdissai was computed as a function of modified Peclet number(Pe′) for various NAPL saturations (SN) and ai during drainage and imbibition and during dissolution without displacement. The largest contributor to ai was the interfacial area in...

During 1997 we evaluated reproductive success in colonial water birds nesting in the Lower Rio Grande Valley (LRGV), Texas, and correlated success with concentrations of contaminants in eggs. We also measured steroid hormones and gonadosomatic index (GSI) as biomarkers of endocrine effects in common carp (Cyprinus carpio). Nest and fledging...

The Charleston Bump is a structural and topographic high on the northern Blake Plateau that overlies a seaward offset of the edge of continental crust. The feature causes the bottom to shoal and deflects the Gulf Stream offshore, causing an intensification of bottom currents. The area has been swept by...

Species are commonly segregated along gradients of microclimate and vegetation. I explore the question of whether segregation is the result of microhabitat partitioning (biotic effects) or choice of differing microclimates (abiotic effects). I explored this question for four ground-nesting bird species that are segregated along a microclimate and vegetation gradient...

Tracer experiments provide information about aquifer material properties vital for accurate site characterization. Unfortunately, density‐induced sinking can distort tracer movement, leading to an inaccurate assessment of material properties. Yet existing criteria for selecting appropriate tracer concentrations are based on analysis of homogeneous media instead of media with heterogeneities typical of...

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...

Remotely triggered cameras have been used in many ecological studies, but most are relatively inexpensive one-time-only systems or expensive infrared systems. We describe the setup and wiring technique for a moderately priced, multiple-photo camera system. Two study areas, California and Vermont, were used to assess usefulness of the camera system....

[No abstract available]...