Famennian

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System/
Period
Series/
Epoch
Stage/
Age
Age (Ma)
Carboniferous Mississippian Tournaisian recent
Devonian Late Famennian 372,2–358,9
Frasnian 382,7–372,2
Middle Givetian 387,7–382,7
Eifelian 393,3–387,7
Early Emsian 407,6–393,3
Pragian 410,8–407,6
Lochkovian 419,2–410,8
Silurian Pridoli no faunal stages defined older
Subdivision of the Devonian system according to the ICS.[1]

The Famennian is one of two faunal stages in the Late Devonian epoch. It lasted from 372.2 ± 1.6 million years ago to 358.9 ± 0.4 million years ago. It was preceded by the Frasnian stage and followed by the Tournaisian stage.

It was during this age that tetrapods first appeared. In the seas, a novel major group of ammonoid cephalopods called clymeniids appeared, underwent tremendous diversification and spread worldwide, then just as suddenly went extinct.

The beginning of the Famennian is marked by a major extinction event, and the end with a smaller but still quite severe extinction event.

North American subdivisions of the Famennian include the Chautauquan, Canadaway, Conneaut, Conneautan, Conewango and Conewangan.

Name and definition[edit]

The Famennian stage was proposed in 1855 by Belgian geologist André Hubert Dumont and was accepted for the upper stage of the Upper Devonian by the Subcommission on Devonian Stratigraphy in 1981.[2] It is named after Famenne, a natural region in southern Belgium.

Fauna[edit]

References[edit]

  1. ^ "International Chronostratigraphic Chart". International Commission on Stratigraphy. Retrieved 9 December 2012. 
  2. ^ Thorez, Jacques; Dreesen, Roland; Streel, Maurice (2006). "Frasnian". Geologica Belgica 9 (1-2): 27–45. Retrieved 16 March 2013. 

See also[edit]