Kasimovian

The Kasimovian is in the geologic timescale, third stage of Pennsylvaniums ( Carboniferous). The stage includes geochronological the period from about 307 million to about 303.7 million years. The Kasimovian following the Moscovian and is detached from the Gzhelium, the lowest level of the Permian.

Naming and history

The Kasimovian is named after the Russian city Kasimov. This time interval was in 1926 by Boris Danschin ( 1891-1941 ) was separated from the upper part of the Moscovian stage as " Teguliferina - horizon ", and later as Kasimov horizon named ( Danschin, 1947; posthumously ). Georgy I. Teodorovic (1949 ) finally named this section as Kasimov level.

Definition and GSSP

The lower limit of Kasimoviums located near the base of the Obsoletes obsoletes - Protriticites pseudomontiparus - fusulinids zone, or the first appearance of the ammonite genus Parashumardites. The upper limit is zethu near the first appearance of the fusulinids genera Daixina, Jigulites and Rugosofusulina, or the Erstvorkommen the conodont species Streptognathodus. A reference profile ( GSSP = Global Stratotype Section and Point) for the base of Kasimovian has not yet been determined.

Subdivision

The Kasimovian is divided into three conodont zones:

  • Idiognathodus toretzianus zone
  • Idiognathodus Sagittatus zone
  • Streptognathodus excelsus / Streptognathodus makhlinae zone
Mya (unit) Cisuralian Asselian Gzhelian Moscovian (Carboniferous) Bashkirian Serpukhovian Devonian Famennian History of the Earth Fusulinida
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