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  2. Geologic time scale - Wikipedia

    en.wikipedia.org/wiki/Geologic_time_scale

    Principles. The geologic time scale is a way of representing deep time based on events that have occurred throughout Earth's history, a time span of about 4.54 ± 0.05 Ga (4.54 billion years). [5] It chronologically organises strata, and subsequently time, by observing fundamental changes in stratigraphy that correspond to major geological or ...

  3. Age of Earth - Wikipedia

    en.wikipedia.org/wiki/Age_of_Earth

    The age of Earth is estimated to be 4.54 ± 0.05 billion years (4.54 × 109 years ± 1%).[1][2][3][4] This age may represent the age of Earth 's accretion, or core formation, or of the material from which Earth formed. [2] This dating is based on evidence from radiometric age-dating of meteorite [5] material and is consistent with the ...

  4. History of Earth - Wikipedia

    en.wikipedia.org/wiki/History_of_Earth

    Earth formed around 4.54 billion years ago, approximately one-third the age of the universe, by accretion from the solar nebula. [4][5][6] Volcanic outgassing probably created the primordial atmosphere and then the ocean, but the early atmosphere contained almost no oxygen.

  5. Timeline of natural history - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_natural_history

    The Ca-Al-rich inclusions, which formed 2 million years before the chondrules, [1] are a key signature of a supernova explosion. c. 4,567 ±3 Ma – Rapid collapse of hydrogen molecular cloud , forming a third-generation Population I star , the Sun , in a region of the Galactic Habitable Zone (GHZ), about 25,000 light years from the center of ...

  6. Geological history of Earth - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_Earth

    The geological history of the Earth follows the major geological events in Earth's past based on the geological time scale, a system of chronological measurement based on the study of the planet's rock layers (stratigraphy). Earth formed about 4.54 billion years ago by accretion from the solar nebula, a disk-shaped mass of dust and gas left ...

  7. Early Earth - Wikipedia

    en.wikipedia.org/wiki/Early_Earth

    According to evidence from radiometric dating and other sources, Earth formed about 4.54 billion years ago. [7] [8] [9] The current dominant theory of planet formation suggests that planets such as Earth form in about 50 to 100 million years but more recently proposed alternative processes and timescales have stimulated ongoing debate in the planetary science community. [10]

  8. Million years ago - Wikipedia

    en.wikipedia.org/wiki/Million_years_ago

    Million years ago, abbreviated as Mya, Myr (megayear) or Ma (megaannum), is a unit of time equal to 1,000,000 years (i.e. 1 × 106 years), or approximately 31.6 teraseconds.

  9. Late Triassic - Wikipedia

    en.wikipedia.org/wiki/Late_Triassic

    2010 [7] The Late Triassic is the third and final epoch of the Triassic Period in the geologic time scale, spanning the time between 237 Ma and 201.4 Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. The corresponding series of rock beds is known as the Upper Triassic.