Sacmarium

from Wikipedia, the free encyclopedia
system series step ≈ age ( mya )
higher higher higher younger
Perm Lopingium Changhsingium 251.9
⬍
254.2
Wuchiapingium 254.2
⬍
259.9
Guadalupium Capitanium 259.9
⬍
265.1
Wordium 265.1
⬍
268.8
Roadium 268.8
⬍
272.3
Cisuralium Kungurium 272.3
⬍
279.3
Artinskium 279.3
⬍
290.1
Sacmarium 290.1
⬍
295.5
Asselium 295.5
⬍
298.9
deeper deeper deeper older

The sakmarian is in the geological a chronostratigraphic stage of the Permian or the Cisuralium . Expressed in absolute terms ( geochronologically ), the level ranges from about 295.5 million years to about 290.1 ​​million years. The Sacmarium follows the Asselium and is replaced by the Artinskium .

Naming and history

The Sakmarium is named after the tributary Sakmara of the Urals in the Ural Mountains . The stage and name were originally proposed by Alexander Karpinski in 1874 as a sub-unit of the Artinskium .

Definition and GSSP

The beginning of the sacmarium was placed at the base of the first appearance of the conodont species Streptognathodus postfusus . The end of the stage is reached with the first appearance of the conodont species Sweetognathus whitei and Mesogondolella bisselli . A GSSP (globally valid type locality and type profile) has not yet been ratified.

literature

  • Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2004, ISBN 978-0-521-78673-7
  • Hans Murawski & Wilhelm Meyer: Geological dictionary . 10., rework. u. exp. Ed., 278 pages, Enke Verlag, Stuttgart 1998, ISBN 3-432-84100-0 .

Web links