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Experiments involving dietary toxicity and residue relationships of DDT, dieldrin, and endrin were conducted with short-tailed shrews. Dietary concentrations of DDT dissolved in vegetable oils were usually more toxic than diets containing comparable amounts of powdered DDT. Younger shrews, particularly females, were more tolerant of powdered DDT than older animals;...

Petrologic and sulfur isotopic studies have been carried out on drill core samples from a roll-type uranium deposit in the mid-Tertiary Catahoula Tuff, Webb County, south Texas. Epigenetic iron disulfide minerals formed in two distinct stages. The first stage involved sulfidization of the host rock by sulfide (H 2 S, HS-)-bearing solutions...

No abstract available....

This study describes gonadal changes in lizards (Uta stansburiana) exposed to chronic low levels of γ radiation (1.5-10 R/day) under field conditions and attempts to evaluate endocrine involvement in these changes. Reproductive impairment in irradiated males is demonstrated during the breeding season by reduced testes weights and by seminiferous tubules...

Over the eastern Snake River Plain, the Bouguer gravity anomaly and the magnetic intensity are, in general, high. In detail, both the gravity and the magnetic anomalies are a complex of highs and lows, in contrast to the simpler anomalies over the western Snake River Plain. The broad gravity high...

Soil samples were collected in two parallel traverses across the Dome fault zone of the Roosevelt Hot Springs Known Geothermal Resource Area. The samples were sealed in air-tight aluminum cans, and the soil gas was allowed to equilibrate with the atmospheric air in the cans. Gas from the cans was...

The type-species of Tribolbina Latham, 1932, T. carnegiei, and T. gigantea (Jones, Kirkby, and Brady, 1884) are redefined and reillustrated, and lectotypes for both are designated. T. permiana (Kellett, 1933) and T. tumida (Scott and Borger, 1941) are also redefined and reillustrated. Beyrichiana Kellett, 1933, is considered a junior subjective...

Soil-gas samples were collected in two parallel traverses across the Dome fault zone of the Roosevelt Hot Springs Known Geothermal Resource Area. Gas chromatographic analyses of the samples showed anomalous concentrations of CS3 and COS east of the Dome fault; higher concentrations of CS2 and COS also occurred over an...

Petrographic properties of sandstone samples from the lower and middle Pennsylvanian Breathitt Formation in northeastern Kentucky and southwestern West Virginia were utilized to classify their environments of deposition. Simultaneous consideration of mineral composition, grain size, and sorting of the sandstones by using stepwise multiple discriminant-function analysis has permitted differentiation between...

Four new pollen species are described on the basis of specimens from the Paleocene to early middle Eocene interval of the Gulf and Atlantic Coastal Plains. The species and their known geologic and geographic ranges are Trivestibulopollenitcs fissuratus (Midwayan to early Sabinian, Claibornian?; gulf coast?, Georgia to South Carolina); Pseudoplicapollis...

A broad apron of pyroclastic-flow deposits derived from dacitic domes of Holocene age at Black Butte and Shastina covers an area of more than 110 km2 on the west flank of Mt. Shasta volcano. The stratigraphy of the deposits is exposed in readouts along a northwest-southeast line between the cities...

Lead-silver deposits in the Wood River mining district occur in shear zones in hornfelsed argillite of the Devonian Milligen Formation near granitic plutons and under the Wood River thrust fault. The principal ore minerals are argentiferous galena and sphalerite; siderite is the principal gangue. The δ34S values of the sulfide...

A fauna of bivalve mollusks, scattered gastropods, and an echinoid from exposures of the Skonun Formation in the northeastern part of Graham Island is indicative of an early late Miocene age and correlation with the provincial Wishkahan Stage. The molluscan assemblages are from the upper 600 of the 1800-m-thick marine...

Characteristic features of fault-generated range fronts, such as those on the Humboldt and Tobin Ranges, include sets of elongate basins extending normal to the range crest, interbasin spurs having crests sloping 10° to 20° toward the range front, spur facets having slopes of 25° to 35°, basin headwalls having slopes...

In the Feather River area, California, and in the McGrath quadrangle, Alaska, axinite-bearing veins occur as fracture fillings along or near the fault zones, suggesting that boron was introduced along the fractures. An unusual occurrence of axinite as a possible primary constituent of a plutonic rock is in the Russian...

No abstract available. ...

The plate tectonics model of the Pacific moving northwest relative to North America implies that the regional strain in California should be simple shear across a vertical plane striking N45°W or equivalently equal parts of north-south contraction and east-west extension. Measurements of the strain accumulation at seven separate sites in...

Whole rock potassium-argon ages for samples of subsurface basalt recovered near Charleston, South Carolina, are interpreted to indicate a Triassic or Jurassic age for the basalt and underlying sedimentary red beds. This age is consistent with existing evidence indicating that an early Mesozoic basin is present in the subsurface of...

Carbon and oxygen isotope analysis through a 30-year (1944 to 1974) growth of Montastrea annularis from Hen and Chickens Reef (Florida Keys) shows a strong yearly variation in the abundances of both carbon-13 and oxygen-18 and a broad inverse relationship between the two isotopes. Normal annual dense bands are formed during the...

The city of San Bernardino is in a semiarid inland valley about 60 miles (100 kilometers) east of Los Angeles. The southern part of the city is traversed by the San Jacinto fault. Adjacent to the upgradient (northeast) side of the fault is a 10 square mile (26 square kilometers)...

Computer-aided techniques for interpreting multispectral data acquired by Landsat offer economies in the mapping of land cover. Even so, the actual establishment of the statistical classes, or "signatures," is one of the relatively more costly operations involved. Analysts have, therefore, been seeking cost-saving signature extension techniques that would accept training...

The Pecora IV Symposium (Applications of Remote Sensing Data to Wildlife Management) conducted October 10-12, 1978, in Sioux Falls, S.D.; provided a perspective on the uses of remote sensing techniques for wildlife management. The task of summarizing the Symposium, which is the objective of this paper, is not simple...

The habitat value for elk and sage grouse of two proposed phosphate strip mine sites was determined using habitat parameter measurements from high-altitude color infrared aerial photographs. Habitat suitability was assessed using the Habitat Evaluation Procedures being developed by the U.S. Fish and Wildlife Service. Similar results were...

The purpose of the study was to determine vegetation succession trends; produce a current vegetation map of the basin; and to develop a mathematical model capable of predicting vegetation changes based on hydrologic factors. A statistical relationship of forests and hydrological variables with forest succession constraints predicted forest acreage...

No abstract available....