Sakmarian

System/
Period		 Series/
Epoch		 Stage/
Age		 Age (Ma)
Triassic Lower/
Early		 Induan younger
Permian Lopingian Changhsingian 252.2–254.1
Wuchiapingian 254.1–259.8
Guadalupian Capitanian 259.8–265.1
Wordian 265.1–268.8
Roadian 268.8–272.3
Cisuralian Kungurian 272.3–283.5
Artinskian 283.5–290.1
Sakmarian 290.1–295.0
Asselian 295.0–298.9
Carboniferous Pennsylvanian Gzhelian older
Subdivision of the Permian system
according to the ICS (Geologic Time Scale 2013).[1]

In the geologic timescale, the Sakmarian is an age or stage of the Permian. It is a subdivision of the Cisuralian epoch or series. The Sakmarian lasted between 295.0 ± 0.18 and 290.1 ± 0.26 million years ago (Ma). It was preceded by the Asselian and followed by the Artinskian.[2]

Stratigraphy

The Sakmarian stage is named after the Sakmara River in the Ural Mountains, a tributary to the Ural River. The stage was introduced into scientific literature by Alexander Karpinsky in 1874. In Russian stratigraphy, it originally formed a substage of the Artinskian stage. Currently, the ICS uses it as an independent stage in its international geologic timescale.

The base of the Sakmarian stage is laid with the first appearance of conodont species Streptognathodus postfusus in the fossil record. A global reference profile for the base (a GSSP) had in 2009 not yet been appointed. The top of the Sakmarian (the base of the Artinskian) is defined as the place in the stratigraphic record where fossils of conodont species Sweetognathus whitei and Mesogondolella bisselli first appear.

References

Notes

  1. ↑ "Chronostratigraphic chart 2013". ICS. Retrieved 27 March 2013.
  2. ↑ See Gradstein et al. (2004) for a detailed geologic timescale

Literature

External links