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U-Pb ages of uranium ores in the Churchrock uranium district, New Mexico

No abstract available.
Authors
K. R. Ludwig, Bruce Rubin, Neil Fishman, Richard L. Reynolds

Continuous subaqueous deposition of the Permian Castile evaporites, Delaware Basin, Texas and New Mexico

Structures that are common in the Castile Formation (Ochoan) of the Delaware Basin, Texas and New Mexico (Fig. 1) include fine planar laminations, breccias, microfolded laminae, and nodular anhydrite. These structures, particularly the laminae, have been used to demonstrate the subaqueous depositional history of the Castile (Anderson and Kirkland, 1966; Anderson et al., 1972; Dean et al., 1975; De
Authors
Walter E. Dean, Roger Anderson

Uranium-lead isochron age and preliminary sulfur isotope systematics of the Felder uranium deposit, south Texas

Uranium-lead isotope systematics of roll-front ores in Miocene sandstone at the Felder and McLean uranium deposits (south Texas coastal plain) give a well-defined 207 Pb/ 204 Pb- 235 U/ 204 Pb isochron age of 5.07 + or - 0.15 m.y. The relatively slight degree of scatter of the points defining the isochron is probably due to initial Pb isotope inhomogeneity, and the resulting inferred persistence o
Authors
K. R. Ludwig, Martin B. Goldhaber, Richard L. Reynolds, Kathleen R. Simmons

Biogenic and nonbiogenic ore-forming processes in the south Texas uranium district; evidence from the Panna Maria deposit

Geochemical and petrographic studies of core samples from the Panna Maria uranium deposit, a roll-type orebody in the Eocene Jackson Group in Karnes County, Texas, yield important information on the origin of the deposit. Organic carbon content averages about 0.42 weight percent in reduced rock and correlates postively with sulfur content. Pyrite is the dominant iron disulfide (FeS 2 ) mineral in
Authors
Richard L. Reynolds, Martin B. Goldhaber, D. Carpenter

Origin of the Mariano Lake uranium deposit, McKinley County, New Mexico

The Mariano Lake uranium deposit, hosted by the Brushy Basin Member of the Jurassic Morrison Formation, occurs in the trough of an east-west trending syncline at the western end of the Smith Lake-Mariano Lake group of uranium deposits near Crownpoint, New Mexico. The orebody, which contains abundant amorphous organic material, is situated on the reduced side of a regional reduction-oxidation (redo
Authors
Neil S. Fishman, Richard L. Reynolds

Origin of organic-carbon-rich mid-Cretaceous limestones, Mid-Pacific Mountains and southern Hess Rise

Limestones of mid-Cretaceous age containing as much as 8.6 percent organic carbon were cored at one site (463) in the Mid-Pacific Mountains and at two sites (465, 466) on southern Hess Rise, central North Pacific Ocean, during Leg 62 of the Deep Sea Drilling Project. In the Mid-Pacific Mountains, three layers containing more than 2% organic carbon are associated with volcanic ash in silicified lim
Authors
Walter E. Dean, G. E. Claypool, Jorn Thiede

The geologic history of the Mid-Pacific Mountains in the central North Pacific Ocean; A synthesis of deep-sea drilling studies

The Mid-Pacific Mountains constitute one of the largest aseismic rises in the central North Pacific Ocean. They have been generated by mid-plate volcanic events prior to Barremian time, but their volcanic activity continued through the remainder of the Cretaceous. Evidence of the latest stages of this volcanism are the trachytic ashes included in mid- and Late Cretaceous sediments and the presence
Authors
Jorn Thiede, Walter E. Dean, David K. Rea, T.L. Vallier, Charles Adelseck

The geology of Hess Rise, central north Pacific Ocean

The geology of Hess Rise is interpreted from studies of morphology and structure, igneous petrology, sediment lithofacies, seismic stratigraphy, and paleoenvironments. Hess Rise probably formed at a triple junction, between 116 and 95 m.y. ago, in the equatorial zone of the southern hemisphere. A large archipelago, formed by volcanism, subsequently moved northward as part of the Pacific Plate and
Authors
T. L. Vallier, David K. Rea, Walter E. Dean, Jorn Thiede, Charles Adelseck

Geological investigation of the Dufek intrusion, Pensacola Mountains, Antarctic

No abstract available.
Authors
A. B. Ford, Richard L. Reynolds, Carl Huie, S. J. Boyer