Subaerial oxidative uranium mobilization at the culmination of the Great Oxidation Event.

ABSTRACT: Redox-sensitive elements figure prominently in studies of the evolution of Earth's surface redox state, including the first major rise in atmospheric O₂, the Paleoproterozoic Great Oxidation Event. Most Precambrian rocks endured multistage tectonothermal histories, however, adding ambiguity to interpretation of their chemistry. Here, we apply U-Th-Pb isotope geochronology to the highly oxidized ~2.06 Ga Kuetsjärvi Volcanic Formation, Pechenga Greenstone Belt, Russia, to constrain the age and extent of U oxidation. By contrasting the relative mobility of U and Th using Pb isotopes, we find that complete to near-complete oxidation and removal of U occurred shortly after eruption. We argue that this likely indicates relatively high atmospheric O₂, where oxidative weather

SUBMITTER: Bauer AM 

PROVIDER: S-EPMC12435218 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature