Serravallium

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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 Serravallian is in the Earth's fourth chronostratigraphic stage of Miocene ( Neogen ) and the upper level of the Middle Miocene. It began geochronologically about 13.82 million years ago and ended about 11.62 million years ago and thus lasted about 2.2 million years. The stage follows the Langhium and is replaced by the Tortonium .

Naming and history

The name of the stage is derived from the place Serravalle Scrivia in the province of Alessandria . The stage and name were introduced by the Italian geologist Lorenzo Pareto in 1864.

Definition and GSSP

The lower limit of the level is defined by the first appearance of the Nannofossil species Sphenolithus heteromorphus . It lies within the magnetic polarity chronozone C5ABr. The upper limit is defined by the last common occurrence of the calcareous Nannofossil species Discoaster kugleri and the planktonic foraminifera species Globigerinoides subquadratus . The limit is associated with the short normal polar magnetic polarity subchrone C5r.2n. The official type profile (GSSP = "Global Stratotype Section and Point") is the Ras-il-Pellegrin profile, Fomm-Ir-Rih-Bucht on the west coast of Malta .

literature

  • Lorenzo Pareto: Note on the subdivision que l'on pourrait established dans les terrains de l'Apennin septentrional. In: Bulletin de la Societé Géologique de France. série 2, 22: 210-277, Paris 1864 ISSN  0037-9409 .
  • Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2004 ISBN 978-0-521-78673-7

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