Ladinium

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system series step ≈ age ( mya )
higher higher higher younger
Triad Upper Triassic Rhaetium 201.3
⬍
208.5
Norium 208.5
⬍
228
Carnium 228
⬍
235
Middle Triassic Ladinium 235
⬍
242
Anisium 242
⬍
247.2
Lower Triassic Olenekium 247.2
⬍
251.2
Indusium 251.2
⬍
251.9
deeper deeper deeper older

The Ladinium (mostly shortened to Ladin in German usage ) is the upper chronostratigraphic level of the Middle Triassic in geological history , which geochronologically corresponds to the period from about 242 to about 235 million years ago and thus lasted about 7 million years. The previous stage is the anisium , the following stage the carnium , which already belongs to the Upper Triassic.

Naming and history

The stage was proposed by Alexander Bittner in 1892 and named after the Ladin ethnic group .

Definition and GSSP

GSSP of the Ladinium, a limestone outcrop near Bagolino in the Italian Alps, a close-up of the " Golden Spike " at the bottom right .

The beginning of the stage is defined by the first appearance of the ammonite species Eoprotrachyceras curionii . The border to Karn has not yet been finally determined. The boundary is probably defined with the first appearance of the ammonite genera Daxatina or Trachyceras , and the first appearance of the conodont species Metapolygnathus polygnathiformis . The GSSP (global type profile) of the Ladinium is located in the Caffaro valley near Bagolino (province of Brescia , Italy ).

Breakdown

The ladinium is divided into four ammonite zones:

Regionally, the Ladin is divided into the lower stages Fassan (Fassanium = lower two ammonite zones) and Longobard (Longobardium = upper two ammonite zones).

Individual evidence

  1. ↑ according to Brack et al. (2005): 241 to 235 million years

literature

  • Alexander Bittner: What is Noric? Yearbook of the Imperial and Royal Geological Institute, 42 (3): 387–396, Vienna 1892 ZDB -ID 217948-9 .
  • Peter Brack, Hans Rieber, Alda Nicora and Roland Mundil: The Global boundary Stratotype Section and Point (GSSP) of the Ladinian Stage (Middle Triassic) at Bagolino (Southern Alps, Northern Italy) and its implications for the Triassic time scale. Episodes, 28 (4): 233-244, Beijing 2005 ISSN  0705-3797 PDF .
  • Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2005, ISBN 978-0-521-78673-7
  • Hans Hagdorn & Adolf Seilacher (eds.): Muschelkalk: International Muschelkalk-Tagung Schöntal 1991 special volumes of the Society for Natural History in Württemberg 2. Stuttgart, basket: Goldschneck-Verl. Weidert, 1993 ISBN 3-926129-11-5
  • Hans Murawski & Wilhelm Meyer: Geological dictionary . 10., rework. u. exp. Ed., 278, Enke Verlag, Stuttgart 1998, ISBN 3-432-84100-0 .

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