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Large submarine lava flows with apparent volumes exceeding 10 km3 have recently been imaged on the deep ocean floor in various parts of the Pacific by means of GLORIA and SeaMarc side‐looking sonar surveys. Such flows may produce thermal anomalies large enough to perturb the cyclic processes of the ocean and...

The 6845 ± 50 BP climactic eruption of Mount Mazama discharged 47 ± 9 km3 of vertically zoned calc-alkaline magma, affording a virtually complete section through the chamber. Evidence for two andesitic parents with different trace-element (particularly Sr) and water contents is preserved in the ejecta. Prior to eruption, a...

Antler anomalies were evident in tule elk (Cervus elaphus nannodes) within 1 yr of reintroduction to Point Reyes, California (USA). These anomalies are consistent with previously described mineral deficiency-induced anomalies in cervids. The elk were judged deficient in copper. Low levels of copper in soils and vegetation at the release...

Research on microbial degradation of crude oil in the shallow subsurface at a spill site near Bemidji, Minn. (fig. C-l), began in 1983 (Hull, 1984; Chang and Ehrlich, 1984). The rate and extent of crude oil and model hydrocarbon biodegradation by the indigenous microbial community was measured in the laboratory...

Azaarenes or aromatic nitrogen heterocycles are a class of compounds found in wood-preservative wastes containing creosote. The fate and movement of these compounds in contaminated aquifers is not well understood. Water-quality studies in an aquifer contaminated with creosote near Pensacola, Florida, indicated that ground water was contaminated with several azaarenes...

No abstract available....

We used an experimental aerial transect survey with stratified random sampling, to estimate the size of the population of wintering black ducks (Anas rubripes) in coastal New Jersey during 2 winters, and the coastal Atlantic Flyway (Me. to S.C.) during 4 years. Population estimates were precise (CV < 0.20) on...

We compared the distribution patterns of winter band recoveries of American black ducks (Anas rubripes) and mallards (A. platyrhynchos) banded in the same breeding areas. Young black ducks wintered northeast of young mallards but no differences in distribution patterns were detected between adult birds of the 2 species. Mallards exhibited...

Waterfowl wintering on the Yazoo National Wildlife Refuge (NWR) were contaminated (ltoreq 4 ppm wet wt) with dichloro diphenyl trichloroethane (DDT) and 1,1-dichloro-2,2-bis-(p-chlorophenyl) ethylene (DDE), but residues were below levels known to affect waterfowl. Eggs of some nesting waterbirds contained higher than expected levels of DDE, especially those of green-backed...

Environmental problems are difficult to solve because their causes and effects are not easily understood. When attempts are made to analyze causes and effects, the principal challenge is organization of information into a framework that is logical, technically defensible, and easy to understand and communicate. When decisionmakers attempt...

The largest historical earthquake in South Carolina, and in the southeastern US, occurred in the Coastal Plain province, probably northwest of Charleston, in 1886. Locations for aftershocks associated with this earthquake, estimated using intensities based on newspaper accounts, defined a northwest trending zone about 250 km long that was at...

Midplate seismicity associated with some former rift-zones is distributed diffusely near, but exterior to, the rift basins. This “basin-exterior” seismicity cannot be attributed to reactivation of major basin-border faults on which upper-crustal extension was concentrated at the time of rifting, because the border faults dip beneath the basins. The seismicity...

The Devonian plant fossil Protosalvinia (Foerstia) has been examined by solid-state 13C nuclear magnetic resonance spectroscopy (NMR) and pyrolysis-gas chromatography-mass spectrometry (PY-GC-MS). Results of these studies reveal that the chemical structure of Protosalvinia is remarkably similar to that of coalified wood. A well-defined phenolic carbon peak in the NMR spectra and the appearance of phenol...

Seismic-reflection profiles across part of the New Madrid seismic zone in northeastern Arkansas and southeastern Missouri show a faulted and structurally complex zone, originally known as Charlie’s ridge but herein renamed Blytheville arch, which is about 10 to 15 km wide and about 110 km long. Several exploratory drill holes...

No abstract available....

This profile, part of a series of profiles concerning coastal habitats of the United States, is a detailed examination of the soft-bottom benthos of San Francisco Bay. A U.S. Fish and Wildlife Service and California Department of Fish and Game report (1979) entitled "Protection and Restoration of San Francisco Bay...

The Rallidae are a diverse group in their habitat selection, yet most North American species occur in or near wetlands As a consequence, most species are subject to habitat enhancement or perturbation from waterfowl management programs. The overall effects of these management programs relative to rallid conservation have...

Whole-body samples of bluegills (Lepomis macrochirus) and common carp (Cyprinus carpio) from the San Joaquin River and two tributaries (Merced River and Salt Slough) were analyzed to determine if the concentrations of any of nine elements were elevated as a result of exposure of the fish to agricultural subsurface (tile)...

The hydraulic potentiomanometer described herein consists of a potentiometer connected to a manometer by a flexible tube. The device is used to directly measure the direction of seepage as well as the hydraulic-head difference between groundwater and surface water. The device works most effectively in sandy materials. For accurate measurements...

Ferromanganese oxide crusts, which accumulate on unsedimented surfaces in the open ocean1–6, derive most of their metal content from dissolved and particulate matter in ambient bottom water7,8, in proportions modified by the variable scavenging efficiency of the oxide phase for susceptible ions9. They differ in this respect from abyssal nodules,...

Jumbo multiple plate samplers were suspended in a river at 0.3 and 1 m depth in one of three orientations: interplate spaces closed to downwelling light and open to flow, open to light and flow, or open to light and closed to flow. Mean numbers of colonizing taxa and individuals...

A simulation study was undertaken to assess the sampling stability of the variable loadings in linear discriminant function analysis. A factorial design was used for the factors of multivariate dimensionality, dispersion structure, configuration of group means, and sample size. A total of 32 400 discriminant analyses were conducted, based on...

No abstract available....

No abstract available....

We investigated the effects of both asymmetries and differing food levels on contest outcomes of wintering Bald Eagles (Haliaeetus leucocephalus) feeding on chum salmon (Oncorhynchus keta) carcasses. Large eagles, regardless of age, were more successful in pirating than smaller eagles. Small pirating eagles were usually unsuccessful unless they were adults...