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Permian chert in the North Fork terrane and correlative rocks of the Klamath Mountains province has a remanent magnetization that is prefolding and presumably primary. Paleomagnetic results indicate that the chert formed at a paleolatitude of 8.6° ± 2.5° but in which hemisphere remains uncertain. This finding requires that these...

The concentrations of Cd, Cr, Cu, Mo, Ni, Sb, U, V, and Zn were measured in early Quaternary sediment (1.32 to 1.08 Ma) from the Oki Ridge in the Japan Sea. The elements were partitioned between a detrital fraction, composed of terrigenous and volcaniclastic aluminosilicate debris, and a marine fraction,...

Regional aquifer systems in the Great Basin consist of carbonate-rock aquifers in the eastern Great Basin and basin-fill aquifers throughout the region. In the carbonate-rock aquifers, barriers to regional flow include Precambrian crystalline basement, upper Precambrian and Lower Cambrian clastic sedimentary rocks, and Jurassic to Tertiary granitic rocks. Basin-fill aquifers...

No abstract available....

The general characteristics of global vegetation during the middle Pliocene warm period can be reconstructed from fossil pollen and plant megafossil data. The largest differences between Pliocene vegetation and that of today occurred at high latitudes in both hemispheres, where warming was pronounced relative to today. In the Northern Hemisphere...

Sedimentological, palynological, and magnetic susceptibility data provide paleoenvironmental and paleoclimatic information from a 989 ft (301 m) core of sediments from the upper Glenns Ferry and Bruneau Formations from near the town of Bruneau in Owyhee County, Idaho. Chronology is based on stratigraphic position, paleomagnetism, and biostratigraphic data, which collectively...

Identification and analyses of Pliocene marine microfossils from 64 globally distributed stratigraphic sequences have been used to produce a middle Pliocene sea surface temperature reconstruction of the Earth. This reconstruction shows little or no change from current conditions in low latitude regions and significant warming of the ocean surface at...

Records of benthic foraminifera from North Atlantic DSDP Site 607 and Hole 610A indicate changes in deep water conditions through the middle to late Pliocene (3.15 to 2.85 Ma). Quantitative analyses of modern associations in the North Atlantic indicate that seven species, Fontbotia wuellerstorfi, Cibicidoides kullenbergi, Uvigerina peregrina, Nuttallides umboniferus, Melonis...

The complex tectonic collage of Alaska is reflected in the conjunction of rocks of widely varying thermal maturity. Indicators of the level of thermal maturity of rocks exposed at the surface, such as vitrinite reflectance and conodont color alteration index, can help constrain the tectonic evolution of such complex regions and, when combined with petrographic, modern...

The relative percentages of diatom taxa in 5 deep-sea cores (DSDP 266, ODP 699A, ODP 747A, ODP 751 A, and Eltanin Core 50-28) from the Southern Ocean are determined for an interval centered on 3.1 to 2.9 Ma in the middle part of the Pliocene. This climatically warm interval, which...

Microfossil assemblages in Pliocene sediments from DSDP Site 274 (68 °59.81′S, 173 °25.64′E) provide data on the age of the sediments and suggest the presence of Nothofagus (southern beech) in Antarctica during the Pliocene. A suite of 17 samples was collected in an interval from Samples 28-274-6R-1, 83–87 cm to 28-274-11R-4, 73–77...

Expansion of the breeding distribution of the Fulvous whistling-duck (Dendrocygna bicolor) into the southeastern United States after the mid-1800s coincided with the establishment of rice (Oryza sativa) cultures in Texas, Louisiana, and Florida. In southern Louisiana, where approximately 80% of rice is aerially seeded in water, Fulvous whistling-ducks are suspected...

No abstract available....

Concentrations of 222Rn in ground water may vary considerably within megascopically homogeneous rocks over relatively short distances. Calculations indicate that different hydraulic apertures of water‐bearing fractures may account for variations in dissolved 222Rn concentration measured in domestic water wells completed in fractured Pikes Peak Granite, assuming that all other factors influencing dissolved 222Rn...

No abstract available. ...

At an active volcano, long-period seismicity (with typical periods in the range 0.2–2 s) reflects pressure fluctuations resulting from unsteady mass transport in the sub-surface plumbing system, and hence provides a glimpse of the internal dynamics of the volcanic edifice. When this activity occurs at shallow depths, it may signal...

The goal of the shelf sediment dynamics component of STRATAFORM is to link sediment transport processes active on the continental shelf to the formation and preservation of event beds in shelf sediment deposits. An approach combining shelf sediment-transport models with high-resolution measurements of water-column and bed properties over periods from...

No abstract available....

The Laguna Madre of Texas supports the most extensive seagrass meadows in the western Gulf of Mexico, In 1988 seagrasses covered 730 km2 or about three-quarters of the embayment. Halodule wrightii dominated the entire upper laguna, and total biomass was quite uniform near 160 g˙m-2 throughout. Four species shared dominance in...

Toxicity tests conducted under field conditions present an interesting challenge for statistical modelling. In contrast to laboratory tests, the concentrations of potential toxicants are not held constant over the test. In addition, the number and identity of toxicants that belong in a model as explanatory factors are not known and...

We tracked 10 ultrasonically tagged shortnose sturgeons Acipenser brevirostrurn during spring in the Merrimack River to investigate spawning. Seven fish in 1989 and six fish in 1990 were tracked intensively to identify the timing and location of spawning and to characterize spawning habitat. In mid‐April 1989 and 1990, fish moved upstream to...

Sediment data were collected for five sediment stations on the lower Missouri and the central Mississippi rivers during the 1993 flood. During the period of June 26 to September 14, 1993, 55 million metric tons was transported past St. Louis, Missouri by the Mississippi River. Sediment was stored in the...

A computer model was used to characterize ground-water flow in Paradise Valley, Nevada, and to evaluate probable long-term effects of five hypothetical development scenarios. One finding of the study is that concentrating pumping at the south end of Paradise Valley may increase underflow from the adjacent Humboldt River valley, and...

Circulating progesterone and prolactin levels were measured in shot and live-caught wild red kangaroos using radioimmunoassays validated for the red kangaroo. The objective of the study was to correlate hormone profiles with reproductive status and determine if red kangaroos follow the general pattern elucidated for other macropodids. During Phase 2a...