Astium

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system series step ≈ age ( mya )
after that after that after that younger
Neogene Pliocene Piacenzium 2.588
⬍
3.6
Zancleum 3.6
⬍
5.333
Miocene Messinium 5.333
⬍
7,246
Tortonium 7,246
⬍
11.62
Serravallium 11.62
⬍
13.82
Langhium 13.82
⬍
15.97
Burdigalium 15.97
⬍
20.44
Aquitanium 20.44
⬍
23.03
before before before older

The Astium , also Astien or Asti level, is a chronostratigraphic level of the Pliocene ( Neogene ) that is no longer valid today in the history of the earth . It was interpreted very differently and therefore had to be abandoned.

Naming and history

The stage and name were proposed by P. de Rouviller in 1857 and introduced into the scientific literature. It is named after the city of Asti , southeast of Turin ( Italy ).

Correlation

The astium of the type locality is represented by shallow water sediments. This facies is generally unsuitable for the definition of a global chronostratigraphic level, as the sequence is very sketchy and usually does not contain any fossils that could be correlated over greater distances. At the type locality, the strata of the Astian can probably be correlated with the Lower and Middle Pliocene. This roughly corresponds to the global chronostratigraphic levels of the Zancleum and the Piacenzium . For example, other authors have referred to a section of profile above the Piacenzian and below the Pleistocene as an Astian. Today this would correspond to the Gelasium ( Quaternary ). Still other authors equated it with the piacenzium. Due to the inadequate definition or the unsuitable type profile and the completely different correlations, the astium was completely abandoned as a chronostratigraphic level and is no longer used as a regional level.

Individual evidence

  1. ↑ cf. Rio, Sprovieri, Castradori and Di Stefano (1998: p. 82)
  2. ↑ z. B. Murawski and Meyer (1998: pp. 13 and 254)
  3. ↑ z. B. Karl Krömmelbein in Brinkmann's Abriß der Geologie, second volume, historical geology. 10/11 Edition from 1977, overview 18 Tertiary in Europe

literature

  • Hans Murawski & Wilhelm Meyer: Geological dictionary . 10., rework. u. exp. Ed., 278 p., Enke Verlag, Stuttgart 1998 ISBN 3-432-84100-0 .
  • Domenico Rio, Rodolfo Sprovieri, Davide Castradori and Enrico Di Stefano: The Gelasian Stage (Upper Pliocene): A new unit of the global standard chronostratigraphic scale . Episodes 21/2: 82-87, Beijing 1998 ISSN  0705-3797 .