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  2. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    Stages 4 and 5 (0.85 Ga–present): O 2 sinks filled, the gas accumulates. [1] Although oxygen is the most abundant element in Earth's crust, due to its high reactivity it mostly exists in compound forms such as water, carbon dioxide, iron oxides and silicates.

  3. 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 ...

  4. 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]

  5. 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]

  6. Timeline of natural history - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_natural_history

    c. 800 Ma – With free oxygen levels much higher, carbon cycle is disrupted and once again glaciation becomes severe – beginning of second "snowball Earth" event c. 750 Ma – First Protozoa appears: as creatures like Paramecium , Amoeba and Melanocyrillium evolve, first animal-like cells become distinctive from plants – rise of herbivores ...

  7. Boring Billion - Wikipedia

    en.wikipedia.org/wiki/Boring_Billion

    The Boring Billion, otherwise known as the Mid Proterozoic and Earth's Middle Ages, is an informal geological time period between 1.8 and 0.8 billion years ago during the middle Proterozoic eon spanning from the Statherian to the Tonian periods, characterized by more or less tectonic stability, climatic stasis and slow biological evolution.

  8. Refinance rates for Thursday, January 9, 2025 - AOL

    www.aol.com/finance/mortgage-and-refinance-rates...

    The unemployment rate edged up moderately to 4.2% from October's 4.1%. A new labor reading for December is due on January 10, 2025 — the first major economic report in the new year.

  9. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    Total atmospheric mass is 5.1480 × 10 18 kg (1.13494 × 10 19 lb), [41] about 2.5% less than would be inferred from the average sea-level pressure and Earth's area of 51007.2 megahectares, this portion being displaced by Earth's mountainous terrain. Atmospheric pressure is the total weight of the air above unit area at the point where the ...

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