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A composite stratigraphic section based on the four DSDP-IPOD Leg 80 drill sites provides a nearly complete record of syn-rift and post-rift events in the vicinity of Goban Spur. Syn-rift sediments were deposited in marginal marine to outer shelf environments. Above the "breakup" unconformity (hiatus spanning most of the Aptian),...

A new method is presented for the direct inversion of seismic refraction data in dipping planar structure. Three recording geometries, each consisting of two common-shot profiles, are considered: reversed, split, and roll-along profiles. Inversion is achieved via slant stacking the common-shot wavefield to obtain a delay time—slowness (tau—p) wavefield....

The modes of occurrence of extractable elements from 21 A and C horizon samples of uncultivated soils were examined using R-mode factor analysis. The extractants (DTPA, EDTA, HCl, hydroquinone, magnesium nitrate, and ammonium oxalate) cover a wide range of chemical attack. Four major elements (Ca, K, Mg, and Na) and...

Peltier coolers were modified and calibrated to serve as soil heat flux transducers. The modification was to fill their interiors with epoxy. The average calibration constant on 21 units was 13.6 ± 0.8 kW m−2 V−1 at 20°C. This sensitivity is about eight times that of the two thermopile transducers with which...

No abstract available. ...

The shallow-water limestones and dolostones of the Conococheague Limestone (Upper Cambrian) of western Maryland contain large amounts of authigenic potassium feldspar. The presence of halite daughter crystals in breached fluid inclusions, low whole-rock ratios of chlorine to bromine, and thermochemical data suggest that the potassium feldspar formed at low temperature...

Since 1978, a large proportion of the black skimmers (Rynchops niger) nesting along the Texas coast have had high concentrations of DDE in their eggs. Of 284 eggs collected from 5 sites during 1978-81, 99.5% contained detectable (> 0.i0 ppm) w levels of DDE, ranging up to 86 ppm wet-weight;...

Samples were analyzed for 12 organochlorine chemicals. Concentrations of DDT + DDD and dieldrin in American white pelican(Pelecanus erythrorhynchos) eggs collected at the Klamath Basin National Wildlife Refuges decreased from 1969 to 1981; DDE and polychlorobiphenyl (PCB) residues did not significantly change. Differences between PCB residues in...

Major portions of the eastern Alaska Range, south of the Denali fault, in the McCarthy, Nabesna, Mount Hayes, and eastern Healy quadrangles, consist predominantly of the Maclaren and Wrangellia tectono-stratigraphic terranes. The Maclaren terrane consists of the Maclaren Glacier metamorphic belt and the regionally deformed and metamorphosed East Susitna batholith....

Similar stratiform sphalerite-galena-barite deposits occur in the Red Dog Creek area, De Long Mountains quadrangle, and in the Drenchwater Creek area, Howard Pass quadrangle, northwestern Brooks Range, Alaska. The deposits, located approximately 180 km apart, are hosted by Mississippian and Pennsylvanian strata of the Kagvik structural sequence of late Paleozoic...

An approximate age for uranium deposits in red beds of the Permian Cutler Formation, Lisbon Valley salt anticline, Utah, was obtained using paleomagnetic techniques. Progressive thermal demagnetization of samples of mineralized sandstone isolates stable magnetization components having high (≳400 °C) unblocking temperatures that define a tilt-corrected mean direction of D...

Feeding Snowy (Egretta thula) and Great (Casmerodius albus) egrets were observed during two breeding seasons in coastal New Jersey and two brief winter periods in northeast Florida. A number of tests based on assumptions of foraging models, predictions from foraging theory, and earlier empirical tests concerning time allocation and movement...

Waters within the north coastal limestoneaquifers are suitable for public supply, industrial and agricultural uses. For the artesian aquifer and the updip parts of the watertable aquifer, calcium and bicarbonate are the dominant ionic species with total dissolved solids and chloride concentrations below 500 and 250 mg/L, respectively. In coastal areas of...

Persistent distribution patterns of woody vegetation within the bottomland forest of Passage Creek, Virginia, were related to fluvial landforms, channel geometry, streamflow characteristics, and sediment—size characteristics. Vegetation patterns were determined from species presence as observed in transects and traverses on landforms developed along the stream. Distinct species distributional patterns were...

No abstract available. ...

In large earthquakes, damaging ground motions may occur at large epicentral distances. Because of the relatively slow speed of seismic waves, it is possible to construct a system to provide short-term warning (as much as several tens of seconds) of imminent strong ground motions from major earthquakes. Automated safety responses...

Three-component seismograms, recorded by a small array of digital instruments in the northern Mississippi embayment, consistently show a high-amplitude phase on the vertical component that arrives approximately 0.8 s before the shear wave. On the basis of its timing and apparent velocity, this phase is identified as an S-P conversion from the...

No abstract available....

Samples dredged from a 15‐m‐high hydrothermal mound atop the flat turbidite pond in the Southern Trough of Guaymas Basin consist of pyrrhotite‐rich massive sulfide, barite, barite + calcite, talc, and opaline silica as well as substrate material composed of fossiliferous, clay‐rich ooze. An 11‐m‐long sediment core taken near the dredge...

Oil shale from the lower part of the Eocene Green River Formation in the Piceance Creek Basin, Colorado, averages 0.13 weight percent fluorine, which is about twice that found in common shales, but is the same as the average amount found in some oil shales from other parts of the...

A new Silurian (Llandoverian) biota from Wisconsin with a significant soft-bodied and lightly sclerotized component is dominated by arthropods and worms. The fauna includes the earliest well-preserved xiphosure, a possible marine uniramian, three new arthropods of uncertain affinity, and possibly the first Paleozoic leech. This may be only the second...

Pelagic limestone units were deposited in the North American Western Interior seaway during two major Cretaceous transgressive episodes. The Bridge Creek Limestone Member of the Greenhorn Formation, deposited during the Late Cenomanian-Early Turonian transgression, and the Smoky Hill Member of the Niobrara Formation, deposited during the overall Early Coniacian-Early Campanian...

The volatile constituents of wolf anal-sac secretions were examined via capillary gas chromatography and compared among intact males, females, castrate males, ovariectomized females, and anosmic and pinealectomized males and females. Some chemical compounds were deemed significantly different (t test, 95% confidence level) among the groups both during and outside of the...

No abstract available....

No abstract available....