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  2. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    Photosynthetic prokaryotic organisms that produced O 2 as a byproduct lived long before the first build-up of free oxygen in the atmosphere, [5] perhaps as early as 3.5 billion years ago. The oxygen cyanobacteria produced would have been rapidly removed from the oceans by weathering of reducing minerals, [citation needed] most notably ferrous ...

  3. Neoproterozoic oxygenation event - Wikipedia

    en.wikipedia.org/wiki/Neoproterozoic_oxygenation...

    The Neoproterozoic Oxygenation Event (NOE), also called the Second Great Oxidation Event, was a geologic time interval between around 850 and 540 million years ago during the Neoproterozoic era, which saw a very significant increase in oxygen levels in Earth's atmosphere and oceans. [1]

  4. Great Oxidation Event - Wikipedia

    en.wikipedia.org/wiki/Great_Oxidation_Event

    The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [2] was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. [3]

  5. Anoxic event - Wikipedia

    en.wikipedia.org/wiki/Anoxic_event

    An anoxic event describes a period wherein large expanses of Earth's oceans were depleted of dissolved oxygen (O 2), creating toxic, euxinic (anoxic and sulfidic) waters. [1] Although anoxic events have not happened for millions of years, the geologic record shows that they happened many times in the past.

  6. Atmospheric chemistry - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_chemistry

    Atmospheric chemistry is a branch of atmospheric science that studies the chemistry of the Earth's atmosphere and that of other planets. This multidisciplinary approach of research draws on environmental chemistry, physics, meteorology, computer modeling, oceanography, geology and volcanology, climatology and other disciplines to understand both natural and human-induced changes in atmospheric ...

  7. 4,000 Meters Below Sea Level, Scientists Have Found the ...

    www.aol.com/4-000-meters-below-sea-134600463.html

    Scientists discovered "dark oxygen" produced by deep-sea polymetallic nodules deep below sea level, redefining our understanding of ocean and early Earth life. 4,000 Meters Below Sea Level ...

  8. Conference foes No. 17 BYU and No. 23 Colorado will square off on Saturday night in the Alamo Bowl in San Antonio. The Cougars (10-2) and Buffaloes (9-3) once had their sights set on a Big 12 ...

  9. Oxygen cycle - Wikipedia

    en.wikipedia.org/wiki/Oxygen_cycle

    The Earth's atmosphere, hydrosphere, and biosphere together hold less than 0.05% of the Earth's total mass of oxygen. Besides O 2, additional oxygen atoms are present in various forms spread throughout the surface reservoirs in the molecules of biomass, H 2 O, CO 2, HNO 3, NO, NO 2, CO, H 2 O 2, O 3, SO 2, H 2 SO 4, MgO, CaO, Al2O3, SiO 2, and ...