Geochemical cycles description

The evolution of atmospheric oxygen is intimately intertwined with the evolution of the Earth, both from a biological and geological perspective. Atmospheric O2 is controlled principally by the long-term (multi-million-year) geochemical cycles of carbon and sulfur. The effect on O2 of the cycles of other elements that exhibit variable oxidation states has been shown to be far less significant quantitatively [11]. The first documented description how the... 

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