Thuringium
The Thuringium , also shortened to Thuring (or also used in the French form Thuringia ), is in the history of the earth a level of the Permian, mostly used in the regional or supra-regional context of the Central European Permian Basin, to a lesser extent internationally . It was initially used synonymously with Zechstein , a rock unit or unit of lithostratigraphy and was therefore basically itself defined lithostratigraphically. Later there were attempts to use the thuringium as a chronostratigraphicEstablish stage. Equating a lithostratigraphic unit with a (supposedly) chronostratigraphic unit is no longer desired in geology today. When defining the limits of the supposedly chronostratigraphic level, there were major problems for various reasons. It is therefore recommended that the term no longer be used today. However, it is of historical interest as it is widely used in older literature, e.g. T. in the paleobotanical literature was used until recently.
History and naming
The thuringium is named after the German state of Thuringia. The term was proposed by the French geologists Ernest Munier-Chalmas and Albert de Lapparent in 1893 and originally referred to the Zechstein in the southern Harz foreland. The term thuringium, like saxonium, was primarily a lithostratigraphic term. Only later did other authors define the basis of the thuringium biostratigraphically with the help of microflora (pollen and spores) and tried to establish the term chronostratigraphically.
Definition and correlation
The lower limit of the Thuringium and thus the limit to the Saxonium is extremely controversial, and the correlation with the international chronostratigraphic structure of the Permian is subject to very large discrepancies. In some correlations, the basis of the thuringium is therefore moved back to the Artinsian region. The youngest Palynofloren in the southern Harz foreland come from the lower Rotliegend. Due to the oxidation of organic material, the Oberrotliegend has practically no microflora. This is where the lower limit of the paleobotanically defined Thuringium lies or “Thuringian” microflora begin in the Asselium / Sakmarium . The “Thuringian” microflora appear well before the Zechstein's transgression in the lower Wuchiapingium , the original lower limit of the lithostratigraphically defined Thuringian.
Due to the great difficulty of establishing a lower limit for the thuringium and the widely differing views on the beginning of the thuringium, Manfred Menning et al. (2005) on the further use of the term.
In the case of the thuringium in particular, it becomes very clear that originally lithostratigraphic terms should not be used chronostratigraphically. Chronostratigraphy and lithostratigraphy are two different methods of structuring rock sequences, whose differently defined terms must not be used synonymously. However, the aim must be to integrate the lithostratigraphic units as precisely as possible into the chronostratigraphic structure. The base of the Zechstein or the transgression of the sea, in which the rocks of the Zechstein were deposited, can now be dated relatively safely to the lower Wuchiapingium .
swell
Individual evidence
- ↑ Spencer G. Lucas, Joerg W. Schneider and Giuseppe Cassinis: Non-marine Permian biostratigraphy and biochronology: an introduction. In: Spencer G. Lucas, Giuseppe Cassinis and Joerg W. Schneider (Eds.): Non-Marine Permian Biostratigraphy and Biochronology. Geological Society, London, Special Publications, 265, 1-14, London 2006 PDF
literature
- Manfred Menning, Reinhard Benek, Jürgen Boy, Bodo-Carlo Ehling, Frank Fischer, Birgit Gaitzsch, Reinhard Gast, Gotthard Kowalczyk, Harald Lützner, Wolfgang Reichel and Jörg W. Schneider: Das Rotliegend in the Stratigraphic Table of Germany 2002 - "Paternoster- Stratigraphy "on the decline. Newsletters on Stratigraphy, 41 (1-3): 91-122, Stuttgart 2005 ISSN 0078-0421