Absolute age of disseminated uraninite in Wheeler Basin, Grand County, Colorado

K.R. Ludwig; E. J. Young

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USGS · 70232774

Absolute age of disseminated uraninite in Wheeler Basin, Grand County, Colorado

K.R. Ludwig·E. J. Young

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Abstract

Uranium and lead isotopic analyses of monazlte and uraninite from the disseminated uraninite occurrence at Wheeler Basin, Grand County, Colo., indicate that these minerals formed 1,446±20 m.y. ago. This time correlates well with intrusion of the Silver Plume Granite. The uraninite and monazite were also affected by a later disturbance at 880±130 m.y., but show essentially no effects of subsequent events. This secondary disturbance may have been due to intrusion of dikes related to the Pikes Peak batholith, dated at 1,041±13 m.y. ago.

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

Source-reported bounding extent: 40.03339786241084° to 40.06651166669528° latitude; -105.68058013916016° to -105.6364631652832° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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K.R. Ludwig, E. J. Young. 1975. Absolute age of disseminated uraninite in Wheeler Basin, Grand County, Colorado. https://pubs.usgs.gov/publication/70232774

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