Pleistocene apparent ages by U-Pb isotope and U-series methods for uranium ore in Dakota Sandstone near Gallup, New Mexico

K. A. Ludwig; Barney J. Szabo; Harry C. Granger

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Pleistocene apparent ages by U-Pb isotope and U-series methods for uranium ore in Dakota Sandstone near Gallup, New Mexico

K. A. Ludwig·Barney J. Szabo·Harry C. Granger

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Abstract

Radiometric dates of a high-grade uranium ore from the Hogback No. 4 mine in Dakota Sandstone near Gallup, N. Mex., indicate a late Pleistocene age of mineralization. The 206 Pb/ 238 U and 207 Pb/ 235 U apparent ages of about 70 000 yr and 100000 yr, respectively, are discordant, but are in broad agreement with the discordant 230 Th/ 238 U and 231 Pa/ 235 U apparent ages of 130000 yr and 78000 yr, respectively. Although it is not clear how the analyzed sample relates to the main period of mineralization at this mine, these dates are consistent with previous age limits suggested for Dakota Sandstone uranium-ores.

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Journal of Research of the U.S. Geological Survey Article

Source-reported bounding extent: 35.37337460834958° to 35.652832827451654° latitude; -108.9129638671875° to -108.52294921875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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K. A. Ludwig, Barney J. Szabo, Harry C. Granger. 1977. Pleistocene apparent ages by U-Pb isotope and U-series methods for uranium ore in Dakota Sandstone near Gallup, New Mexico. https://pubs.usgs.gov/publication/70233483

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