Pena Blanca deposit, Chihuahua Mexico

Pearcy, E. C., Prokryl, J. D., Murphy, W. M. Leslie, B. W. 1994. Alteration of uraninite from the Nopal I deposit, Pena Blanca District, Chihuahua, Mexico, compared to degradation of SNF in the proposed U.S. high level nuclear waste repository at Yucca Mountain, Nevada. Applied Geochemistry, 9, 713—732. 

Sierra Pena Blanca district. Chihuahua, Mexico The Pena Blanca uranium district is about 50 km northeast of Chihuahua, Mexico, on the east side of a large Basin and Range horst block and near the eastern edge of the Caenozoic Sierra Madre Occidental volcanic province. The bulk of the uranium deposits, which total about 5000 ton of reasonably assured U3O8 resource, occur in extracaldera ash-flow tuffs overlying Cretaceous limestones. The source of the tuffs is unknown, but some appear to be related to a large caldera south of Chihuahua. Other tuffs appear to have a western source. 

Goodell P. C. Trentham R. C. and Carraway K. Geologic setting of the Pena Blanca uranium deposits. Chihuahua, Mexico. In Formation of uranium ores by diagenesis of volcanic sediments Henry C. D. etal. eds Open-File Rep. U.S. Dep. Energy GJBX-22(79), 1978, 38 p. 

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