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The abundance and distribution of uranium have been determined in 11 units of rhyolitic lava and ash-flow tuff of calc-alkaline and transitional composition from the western United States in order to further evaluate the potential of rhyolitic glass as a source of uranium ores. Samples consist of coexisting obsidians, perlites,...

No abstract available....

Although the Mesozoic-Cenozoic metallogeny of the western United States unquestionably resulted from convergence of the North American and Pacific Ocean plates, subduction alone does not adequately explain the distribution of the ore deposits in Laramide and post-Laramide time, when magmatism and mineralization extended irregularly eastward at least 1500 km from...

No abstract available....

The paleolimnological records of Burntside and Shagawa Lakes in northeastern Minnesota reveal that these two adjacent lakes have been limnologically distinct for many years prior to the late 19th century activities of white men that polluted Shagawa Lake. Although both lakes occur within the same vegetation type and share much...

More than 90% of the known petroleum accumulations west of the San Andreas fault in California are in strata deposited in areally restricted Neogene basins that formed during a major tectonic reorganization of western California. These deep, localized Neogene basins replaced broad, regionally persistent Paleogene depositional aprons, although some of...

We have devised a computer-assisted graphical method for correlating chemical analyses in suites of related igneous rocks. The method provides a direct and empirical means of sample identification using all of the reported chemistry. In a study of basalt of the Columbia River plateau, the method has been used for...

Sequential morphologic changes in pollen of the Momipites‐Caryapollenites lineage from Paleocene strata in the Wind River Basin of Wyoming appear to reflect evolution within the family Juglandaceae. The stratigraphic occurrence of the species within this complex permits the establishment of six biostratigraphic zones that can be correlated between outcropping and subsurface sequences...

No abstract available....

The detrital Fe-Ti oxide minerals and their authigenic alteration products in samples from cores spanning 1.7 km across a roll-type uranium deposit in the mid-Tertiary Catahoula Tuff, south Texas, record important information on host-rock preparation and on development of the altered tongue of the deposit. In reduced rock, in front...

No abstract available....

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...

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...

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...

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...

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...

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...

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...

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...