Anisium

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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 anisium (mostly shortened to anise in German usage ) is the first or lower chronostratigraphic level of the Middle Triassic in geological history . Geochronologically, the stage covers the period from about 247.2 to about 242 million years ago and thus lasted about 5.2 million years. The anise is preceded by the olenekium ; it is being replaced by the ladinium .

Naming and history

The original type locality is near Großreifling in Styria ( Austria ). The name is derived from Anisus , the Latin name of the Enns . The anise level was introduced by Wilhelm Heinrich Waagen and Carl Diener in 1895, and is there in the Reifling formation .

Definition and GSSP

Two horizons are discussed as the lower limit of the stage (and thus also the lower limit of the Middle Triassic ); the first appearance of the conodont species Chiosella timorensis or the base of the magnetozone MT1n. The upper limit of the anisium (and the lower limit of the ladinium ) is defined by the first appearance of the ammonite species Eoprotrachyceras curionii and the onset of the ammonite family Trachyceratidae. The border also coincides with the first appearance of the conodont species Neogondolella praehungarica . In December 2007 the "Subcommission on Triassic Stratigraphy" proposed a location on Deşli Caira Mountain in Dobruja ( Romania ) as a GSSP (global type locality and type profile). Ratification and final confirmation by the IUGS had not yet taken place by 2016. The Ladinium's GSSP has already been established.

Breakdown

In the Tethys area , the level is divided into six ammonite zones:

As an informal sub-stages, the Aegeum, which are mainly in alpine areas Bithynium that Pelsonium and Illyrium used.

Individual evidence

  1. ↑ according to Brack et al. (2005): 248 to 241

literature

  • 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 .
  • Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2005, ISBN 9780521786737
  • 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 .
  • Eugen Grǎdinaru, Michael J. Orchard, Alda Nicora, Yves Gallet, Jean Besse, Leopold Krystyn, Evgeny S. Sobolev, Nicu-Viorel Atudorei and Daria Ivanova: The Global Boundary Stratotype Section and Point (GSSP) for the base of the Anisian Stage : Deşli Caira Hill, North Dobrogea, Romania. Albertiana, 36: 54-71, Utrecht 2007 ISSN  0169-4324 PDF
  • Herbert Summesberger and Ludwig Wagner: The stratotype of the anise (Trias) - Geological description of the profile of Großreifling (Styria). Annals of the Natural History Museum Vienna, 76: 515–538, Vienna 1972 PDF
  • Wilhelm Waagen and Carl Diener: I. Lower Triassic (Scythian and Dinaric series). In: Edmund von Mojsisovics, Wilhelm Waagen and Carl Diener: Draft of a structure of the pelagic sediments of the Triassic system. Meeting reports of the Academy of Sciences in Vienna, mathematical and natural science class, 104: 1278-1296, Vienna 1895.

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