SUMMARY

Uranium in the Nacimiento-Jemez region of north-central New Mexico occurs in rocks of Pennsy lvanian, Permian, Triassic, Jurassic, Cretaceous, and Tertiary age. Deposits consist of uranium minerals disseminated in sandstone, silt-stone, carbonaceous shale, coal, and limestone and in associa-tion with carbonized plant debris in sandstone and in "red bed " copper deposits. Uranium minerals fill interstices of a sil icified rhyolite breccia at a single occurrence. Known de-posits are small and subeconomic. Slightly more than 600 tons of ore have been produced to date