Sheinwoodian

In the geologic timescale, the Sheinwoodian is the age of the Wenlock epoch of the Silurian period of the Paleozoic era of the Phanerozoic eon that is comprehended between 433.4 ± 0.8 Ma and 430.5 ± 0.7 Ma (million years ago), approximately. The Sheinwoodian age succeeds the Telychian age and precedes the Homerian age.[3]

Epochs in the Silurian
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Epochs of the Silurian Period.
Axis scale: millions of years ago.

Definition

The Wenlock-Llandovery boundary is defined by the first occurrence of Cyrtograptus centrifugus. The stage is named after Sheinwood village, north of Much Wenlock. The Buildwas Formation of Shropshire, United Kingdom contains the type section.[4]

Palaeontology

Arthropods

Arthropods of the Sheinwoodian
TaxaPresenceLocationDescriptionImages
Balizoma Sheinwoodian to Gorstian Dudley, England A trilobite with nodular tubercles on its cephalon

Cephalopods

Cephalopods of the Sheinwoodian
TaxaPresenceLocationDescriptionImages
Cameroceras Dapingian-Homerian
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References

  1. Jeppsson, L.; Calner, M. (2007). "The Silurian Mulde Event and a scenario for secundo—secundo events". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 93 (02): 135–154. doi:10.1017/S0263593300000377.
  2. Munnecke, A.; Samtleben, C.; Bickert, T. (2003). "The Ireviken Event in the lower Silurian of Gotland, Sweden-relation to similar Palaeozoic and Proterozoic events". Palaeogeography, Palaeoclimatology, Palaeoecology. 195 (1): 99–124. doi:10.1016/S0031-0182(03)00304-3.
  3. Gradstein, Felix M.; Ogg, James G.; Smith, Alan G. (2004). A Geologic Time Scale 2004. ISBN 9780521786737.
  4. Silurian System


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