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  2. Ordovician - Wikipedia

    en.wikipedia.org/wiki/Ordovician

    The Ordovician–Silurian extinction events may have been caused by an ice age that occurred at the end of the Ordovician Period, due to the expansion of the first terrestrial plants, [54] as the end of the Late Ordovician was one of the coldest times in the last 600 million years of Earth's history.

  3. Late Ordovician mass extinction - Wikipedia

    en.wikipedia.org/wiki/Late_Ordovician_mass...

    The Late Ordovician mass extinction (LOME), sometimes known as the end-Ordovician mass extinction or the Ordovician-Silurian extinction, is the first of the "big five" major mass extinction events in Earth's history, occurring roughly 445 million years ago (Ma). [1]

  4. List of time periods - Wikipedia

    en.wikipedia.org/wiki/List_of_time_periods

    Classical antiquity – Broad term for a long period of cultural history centered on the Mediterranean Sea, comprising the interlocking civilizations of ancient Greece and ancient Rome, collectively known as the Greco-Roman world. It is the period in which Greek and Roman society flourished and wielded great influence throughout Europe, North ...

  5. Cambrian–Ordovician extinction event - Wikipedia

    en.wikipedia.org/wiki/Cambrian–Ordovician...

    Volcanic activity, particularly that of large igneous provinces, has been speculated to have been the cause of the environmental crisis. [3] The emplacement of the Namaqualand–Garies dykes in South Africa has been dated to 485 mya, the time at which the Cambrian–Ordovician extinction event occurred, although there remains no unambiguous evidence of a causal relationship between this ...

  6. List of orogenies - Wikipedia

    en.wikipedia.org/wiki/List_of_orogenies

    Taconic phase – Mountain-building period that affected most of New England – In the northeastern U.S. and Canada, during the Ordovician Period; Acadian phase – North American orogeny – In the eastern U.S., during the Silurian and Devonian Periods

  7. Late Ordovician - Wikipedia

    en.wikipedia.org/wiki/Late_Ordovician

    The Late Ordovician is the third and final epoch of the Ordovician period, lasting 15.1 million years and spanning from around 458.2 to 443.1 million years ago. [ 4 ] [ 5 ] The rocks associated with this epoch are referred to as the Upper Ordovician Series.

  8. Rings of Earth - Wikipedia

    en.wikipedia.org/wiki/Rings_of_Earth

    The Ordovician Period was the geologic period and system that the Earth was in when the rings are believed to have formed. The Ordovician spanned from 486.85 million years ago to 443.1 million years ago. During this period, an event known as the Ordovician meteor event occurred, when a high level of L chondrite meteorites hit Earth. The ...

  9. Hirnantian - Wikipedia

    en.wikipedia.org/wiki/Hirnantian

    In fact, the Hirnantian (also known as the End Ordovician and the Ordovician-Silurian) mass extinction event represents the second largest such event in geologic history. Approximately 85% of marine (sea-dwelling) species died. Only the End-Permian mass extinction was larger. Unlike many smaller extinction events, however, the long-term ...