Ireviken event

Subdivision of the Silurian Period
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Paleozoic
 
 
 
Subdivision of the Silurian according to the ICS, as of 2024.
Vertical axis scale: Millions of years ago

The Ireviken event was the first of three relatively minor extinction events (the Ireviken, Mulde, and Lau events) during the Silurian period. It occurred at the Llandovery/Wenlock boundary (mid Silurian, 432.9 ± 1.2  million years ago). The event is best recorded at Ireviken, Gotland, where over 50% of trilobite species became extinct; 80% of the global conodont species also became extinct in this interval.