Carbon mobility in the Athabasca Basin environment (Saskatchewan, Canada) and impact on the formation of unconformity-related uranium deposits.
E001
Abstract
Unconformity-related uranium deposits are Proterozoic deposits formed in various provinces around the world, including the Athabasca Basin in Canada (Saskatchewan). These hydrothermal deposits, characterized by the highest uranium grades recorded on Earth, form at the unconformity between the sedimentary basin and its crystalline basement, in spatial association with graphite-rich basement shear zones. Carbon (C) is ubiquitous element in the environment of these deposits and is present in various forms (minerals, gases) within the basement and basin. It is considered as a key player in uranium mineralization, although no consensus has yet been reached regarding its role in the mechanisms leading to such exceptional deposits. In this context, this presentation is dedicated to the study of C mobility over time in the metallogenic system under consideration via the study of the various mineral and gaseous C carriers, from the first C enrichments in the shear zones associated with the Trans-Hudsonnian orogen (ca. 1.85-1.75 Ga) to the post-basin emplacement of primary uranium mineralization (ca. 1.6-1.3 Ga) and contemporary C-bearing hydrothermal phases.