Great Oxidation Event · ~2.4 Gya
unseel.com · oxygenic photosynthesis · banded iron · rising O₂
Onset ~2.43 Ga
Driver cyanobacteria
phase
Cyanobacteria mats
O₂ bubbles
Banded iron (Fe³⁺)
O₂ level curve
Cleared sky
Unseel.com · Great Oxidation Event