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  2. Great Oxidation Event - Wikipedia

    en.wikipedia.org/wiki/Great_Oxidation_Event

    This began approximately 2.460–2.426 Ga (billion years) ago ... which get their color ... The currently available evidence suggests that the deep ocean remained ...

  3. Purple Earth hypothesis - Wikipedia

    en.wikipedia.org/wiki/Purple_Earth_hypothesis

    [2] [3] It is estimated to have occurred between 3.5 and 2.4 billion years ago during the Archean eon, prior to the Great Oxygenation Event and Huronian glaciation. [ 4 ] Retinal-containing cell membranes exhibit a single light absorption peak centered in the energy-rich green-yellow region of the visible spectrum , but transmit and reflect red ...

  4. Banded iron formation - Wikipedia

    en.wikipedia.org/wiki/Banded_iron_formation

    The peak of banded iron formation deposition coincides with the disappearance of the MIF-S signal, which is interpreted as the permanent appearance of oxygen in the atmosphere between 2.41 and 2.35 billion years ago. This was accompanied by the development of a stratified ocean with a deep anoxic layer and a shallow oxidized layer.

  5. Samples of Canadian mineral show almost all life was wiped ...

    www.aol.com/news/samples-of-canadian-mineral...

    A new study reveals that all life on earth was obliterated two billion years ago, and the problem was oxygen. Skip to main content. Sign in. Mail. 24/7 Help. For premium support please call: 800 ...

  6. Proterozoic - Wikipedia

    en.wikipedia.org/wiki/Proterozoic

    Until roughly 2.3 billion years ago, oxygen was probably only 1% to 2% of its current level. [9]: 323 The banded iron formations, which provide most of the world's iron ore, are one mark of that mineral sink process. Their accumulation ceased after 1.9 billion years ago, after the iron in the oceans had all been oxidized. [9]: 324

  7. 'Oldest living thing' on earth discovered and it may prove ...

    www.aol.com/news/2015-02-03-the-oldest-living...

    The Oldest Living Organism Is Over 2 Billion Years Old. Scientists have identified the oldest living species on Earth is a deep sea organism that hasn't evolved in more than two billion years. And ...

  8. A giant meteorite boiled the oceans 3.2 billion years ago ...

    www.aol.com/giant-meteorite-boiled-oceans-3...

    When a meteorite with the mass of four Mount Everests hit Earth 3.2 billion years ago, ... were probably green in color from iron-rich deep waters.” ... brought back the top layers of the ocean ...

  9. Canfield ocean - Wikipedia

    en.wikipedia.org/wiki/Canfield_ocean

    In a paper published in 1998 in Nature, [1] Canfield argued that the deep ocean was anoxic and sulfidic (also known as euxinic) during the time of the Boring Billion (1.8–0.8 billion years ago (Gya)), and that those conditions ceased the mineral deposition of iron-rich banded iron formations (BIF) in ocean sediments.