Evolution of the precambrian earth system through progressive oxidation of surface environments

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The redox states of the atmosphere and ocean changed dramatically in the Precambrian. The rise of atmospheric oxygen has been constrained, based on geological and geochemical evidence, to have occurred between ca. 2.45 and 2.32 Ga, during the assembly of the first supercontinent and a series of ca. 2.48-2.42 Ga mantle plume breakouts. This sequence of events led to several perturbations in Earth's surface environment, including global glaciations followed by extreme greenhouse conditions, carbon isotope excursions in seawater composition, the rise of seawater sulfate content, and changes in the ocean redox state. Since these events affected surface environments globally, they have implications not only for the understanding the history and stability of the Earth System, but also for correlation between Paleoproterozoic basins that otherwise lack high precision geochronologic constraints.