Title

G. V. Afanasiev, Yu. B. Mironov, E. M. Pinsky

Unconformity - type uranium deposits and provinces

Unconformity-type uranium deposits are located at the base of superdome epicratonic depressions near surfaces of regional structural stratigraphic unconformities (SSU). The unconformities are subdivided into two subtypes (pre-Upper Karelian and pre-Riphean) based on the age of depressions and SSU and include three varieties depending on conditions of location, morphology of ore deposits, and degree of U concentration (Canadian, Australian and Indian). A hypothesis of stage-by-stage-segregation (concretionary) mechanism of uranium mineralization formation is proposed. Specific features of type varieties can be used as predictive criteria for identifying new targets in different regions of the world, including Russia.
Key words: domes, depressions, sandstone, segregation, nodules.