Ireviken event
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The Ireviken event was the first of three relatively minor
Anatomy of the event
The event lasted around 200,000 years, spanning the base of the Wenlock epoch.[2][4] It is associated with a period of global cooling.[5][6][2]
It comprises eight extinction "datum points"—the first four being regularly spaced, every 30,797 years, and linked to the
Casualties
The mechanism responsible for the event originated in the deep oceans, and made its way into the shallower shelf seas. Correspondingly, shallow-water reefs were barely affected, while pelagic and hemipelagic organisms such as the graptolites, conodonts and trilobites were hit hardest.[7][2]
Geochemistry
Subsequent to the first extinctions, excursions in the δ13C and δ18O records are observed; δ13C rises from +1.4‰ to +4.5‰, while δ18O increases from −5.6‰ to −5.0‰.[2]
See also
References
- .
- ^ .
- ^ "Chart/Time Scale". www.stratigraphy.org. International Commission on Stratigraphy.
- ^ a b c d Jeppsson, L (1997). "The anatomy of the Mid-Early Silurian Ireviken Event and a scenario for P-S events". In Brett, C.E.; Baird, G.C. (eds.). Paleontological Events: Stratigraphic, Ecological, and Evolutionary Implications. New York: Columbia University Press. pp. 451–492.
- .
- . Retrieved 26 December 2022.
- . Retrieved 27 March 2023.