Potential links between intense volcanism and the late-Archean “whiff” of oxygen

The Archean Earth was characterized by a persistent weakly reducing atmosphere, while accumulated geological records suggest occurrence of transient atmospheric oxygenation events—whiff of oxygen—during the late Archean, the precise nature and causes of which remain elusive. We used a biogeochemical model to propose the eruption of large igneous provinces (LIPs) as a plausible mechanistic explanation for the transient oxygenation events in the late Archean atmosphere. Here we show that biogeochemical dynamics induced by LIP eruptions could have caused transient increase in the level of atmospheric oxygen (O2) for more than several million years. Notably, continental growth during the late Archean would have mitigated the conditions for transient oxygenation, suggesting that the late Archean Earth system approached a tipping point for permanent oxidation of the atmosphere. The late Archean atmosphere might have evolved dynamically through interactions with the ocean and the biosphere, modified by LIP eruptions.