How Water Made Earth Livable for Us - The Peroxy Way

From SPACE.com:

Living on a planet with an oxygen-rich atmosphere we tend to forget that our planet is an anomaly. About 4.5 billion years ago, when the solar system accreted out of a disk of gas and dust, the Earth was thoroughly reduced. Over the course of the first 1-2 billion years our planet became slowly, but inextricably ever more oxidized. Vast amounts of iron rich sediments precipitated out of the oceans, known as "Banded Iron Formations" or BIFs, indicating that reduced ferrous iron, Fe2+, converted into ferric iron, Fe3+. This required a large, sustained supply of oxidizing power.

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