Journal of the Geological Survey of Brazil (May 2018)
A hydrothermal karst-hosted U-P deposit related to Pangea break-up: Itataia deposit, Borborema Province, Northeastern Brazil - a review
Abstract
The Itataia U-P deposit holds the second largest uranium reserve in Brazil. All of the uranium is contained within the microcrystalline structure of fluorapatite, which is the ore mineral of the collophanite bodies. The main lithology that hosts the mineralization is marble, and the collophanite occurs as massive bodies, stockwork vein, breccia, filling vugs in episyenites, and disseminated in host rocks. This review shows that five important episodes in the Northern Borborema Province, leading to the consolidation of the Itataia U-P deposit: i) deposition of a phosphate-rich Neoproterozoic supracrustal quartz-pelite-carbonate sequence, represented by the Itataia Group; ii) building of the Neoproterozoic Tamboril-Santa Quitéria continental magmatic arc, responsible for the partial melting of the phosphate-rich supracrustal sequence; iii) Na-metasomatism related to Neoproterozoic/Cambrian-Ordovician post-collisional to anorogenic granitoids, which generated uranium-rich albitite, as well as barren episyenite bodies; iv) Cretaceous hydrothermal karstic event related to the generalized fracturing of the continental crust caused by the Pangea break-up and making possible the deposition of collophanites in the karstic features and vugs in episyenites; v) reworking of the collophanites with the deposition of breccia in paleokarstic features in the marble.