Tortonium

from Wikipedia, the free encyclopedia
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 Tortonium (often shortened to Torton) is the fifth chronostratigraphic stage of the Miocene ( Neogene ) in the history of the earth . It began geochronologically about 11.62 million years ago and ended about 7.246 million years ago and thus lasted about 4.3 million years. The step follows the Serravallium and is replaced by the Messinium .

Naming and history

The stage is named after the city of Tortona in the province of Alessandria , Piedmont region ( Italy ). The step and the name were introduced by the Swiss geologist Karl Mayer-Eymar in 1858.

Definition and GSSP

The lower limit of the level 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 upper limit is defined by the lowest occurrence of the planktonic foraminifera species Globorotalia conomiozea . The limit lies roughly in the middle of the magnetic polarity chronozone C3Br.1r. The official type profile of the International Commission for Stratigraphy (GSSP = “Global Stratotype Section and Point”) is the Monte dei Corvi beach profile near Ancona ( Italy ).

literature

  • Karl Mayer-Eymar: Attempting a new classification of the tertiary structures of Europe . Negotiations of the Swiss Natural Research Society. (Annual meeting from August 17–19, 1857 in Trogen), pp. 70–71 et 165–199 et table, Basel 1858.
  • Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2004 ISBN 978-0-521-78673-7
  • Frederik Hilgen, Hayfaa Abdul Aziz, David Bice, Silvia Iaccarino, Wout Krijgsman, Klaudia Kuiper, Alessandro Montanari, Isabella Raffi, Elena Turco and Willem-Jan Zachariasse: The Global boundary Stratotype Section and Point (GSSP) of the Tortonian Stage (Upper Miocene ) at Monte Dei Corvi. Episodes, 28: 6-17, Beiing 2005 ISSN  0705-3797 PDF .
  • Hans Murawski & Wilhelm Meyer: Geological dictionary . 10., rework. u. exp. Ed., 278 p., Enke Verlag, Stuttgart 1998 ISBN 3-432-84100-0 .

Web links