Sandstone-hosted uranium deposits at the Cebolleta Land Grant, Cibola County, New Mexico
— Ted Wilton, Chavez, William X., Jr., and Samatha Caldwell


The Cebolleta Land Grant of west-central New Mexico is the site of five sandstone-hosted uranium deposits that represent the northeastern extension of the prolific Jackpile–Paguate uranium mineralized zone and the northern part of the Laguna mining district. The uranium mineralization at Cebolleta, which is hosted in the Jackpile Sandstone Member of the Upper Jurassic Morrison Formation, has been extensively delineated by more than 1,000 drill holes, two open pit mines, and three underground mines. The mineralization occurs as a series of generally tabular-shaped bodies that were deposited within various lenses of the Jackpile Sandstone. Individual uranium deposits at the land grant exhibit many of the characteristics of primary, redistributed, and remnant types of uranium deposits that are hosted in the Westwater Canyon Member of the Morrison Formation elsewhere within the Grants Mineral Belt. Coffinite and minor uraninite are the principal primary uranium minerals in the deposits. Secondary uranium minerals, which are the result of post-mining oxidation of the primary coffinite and uraninite-rich zones, are exposed in the two former St. Anthony open pits. Significant unmined uranium mineralization is present in the area of the former mines, between and adjoining the now inactive St. Anthony and JJ#1 mines, and extending to the northeast of the former mines.

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Recommended Citation:

  1. Wilton, Ted; Chavez, William X., Jr.; Caldwell, Samatha, 2021, Sandstone-hosted uranium deposits at the Cebolleta Land Grant, Cibola County, New Mexico, in: New Mexico Geological Society, 71st Annual Fall Field Conference, September 2021, Geology of Mount Taylor, Frey, Bonnie A.; Kelley, Shari A.; Zeigler, Kate E.; McLemore, Virginia T.; Goff, Fraser; Ulmer-Scholle, Dana S., new Mexico Geological Society, Guidebook, pp. 171-182.

[see guidebook]