Title: Stagewise oxygenation of the Earth's atmosphere and oceans
Author: Haiyang Wang, Chao Li
Journal: The Innovation
Date of Publication: March 14, 2026
Link: https://doi.org/10.1016/j.xinn.2026.101353
Abstract：Earth's surface oxygenation was a protracted, multi-step process. It is widely accepted that atmospheric O2 rose through three major steps, each closely linked to key evolutionary innovations. Recent advances, particularly in sulfate triple-oxygen isotope records, now provide new constraints on the timing, tempo, and magnitude of atmospheric oxygenation. These data reveal a positive coupling between atmospheric and oceanic oxygenation on billion-year timescales, with stagewise rises in atmospheric O2 consistently preceding oceanic responses, whereas on shorter, million-year timescales, their redox states could diverge, exhibiting negative coupling. Oceanic redox evolution was also spatially and temporally heterogeneous, progressing from localized Archean oxygen oases (>3.0 Ga) to a globally oxygenated state by the Paleozoic (<0.41 Ga). Here, we synthesize geochemical, sedimentological, and palaeobiological evidence to reconstruct this coupled and dynamic atmosphere-ocean oxygenation history and to reassess its timing, mechanisms, and ecological consequences. These deep-time perspectives illuminate the co-evolution of life and Earth's surface environments and provide a conceptual framework for evaluating planetary habitability.
