Sub-arc mantle fugacity shifted by sediment recycling across the Great Oxidation Event

Abstract The chemical exchange between the atmosphere, crust and mantle depends on sediment recycling via subduction. However, it remains unclear how atmospherically modified may affect oxygen fugacity through time. Great Oxidation Event, among most important atmospheric changes Earth, offers an opportunity to investigate in magmatism related surface–mantle interactions. Here we use sulfur K-edge micro X-ray absorption near-edge structure spectroscopy measure relative abundances of S 6+ , 4+ 2− state apatite inclusions hosted 2.4–2.1-billion-year-old igneous zircons from Mineiro Belt, Brazil. host magmas record intracrustal melting juvenile involvement recycled sediments sub-arc wedge. Unaltered reveal a change reduced more oxidized pre- post-Great Event during early Proterozoic. We argue that this is direct result deep subduction thus evidence mantle–atmosphere interaction across Event. This suggests onset Archaean provided access mantle, ‘whiffs’ have already contributed localized increase calc-alkaline ore deposits Earth.