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Phenomena

Late Ordovician Mass Extinction

Stratigraphy

The first of the Phanerozoic eon's five major mass extinctions, occurring around 445 million years ago at the boundary between the Ordovician and Silurian periods. Nearly 85 percent of marine species were eliminated in two closely spaced extinction pulses, widely linked to a rapid glaciation and sea level fall followed by expanding ocean anoxia as the ice sheets melted. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Magnitude or Scale
Nearly 85 percent of marine species eliminated, with an estimated 49 to 60 percent of marine genera lost, across two extinction pulses. 1
Location
Global, with effects concentrated in shallow marine ecosystems. 1
Connections

Associated With

Ordovician, Eras
Source Late Ordovician Mass Extinction (Wikipedia)
Silurian, Eras
Source Late Ordovician Mass Extinction (Wikipedia)

Caused By

Glaciation, Processes
Source Late Ordovician Mass Extinction (Wikipedia)

In Discipline

Stratigraphy, Disciplines
Sources
1. Late Ordovician Mass Extinction (Wikipedia)
Wikimedia Foundation
  • Lead section
    The Late Ordovician mass extinction (LOME), sometimes referred to 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).
  • Article text
    Extinction was global during this interval, eliminating 49-60% of marine genera and nearly 85% of marine species.
  • Associated With: Ordovician
  • Associated With: Silurian
  • In Group: Mass Extinction Events, Lead sentence
    The Late Ordovician mass extinction (LOME), sometimes referred to 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). It is often considered to be the
  • Caused By: Glaciation, Lead sentence
    This extinction pulse is typically attributed to the Late Ordovician glaciation, which abruptly expanded over Gondwana at the beginning of the Hirnantian and shifted the Earth from a greenhouse to icehouse climate.
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