|system||series||step||≈ age ( mya )|
The tithonium (in German often shortened to tithon , more rarely also tithonia, until 1990 partly also referred to as portlandium ) is the highest chronostratigraphic level of the Jurassic and lasted geochronologically from about 152.1 to about 145 million years. The Tithonium follows the Kimmeridgium and is replaced by the Berriasium , the lowest level of the Lower Cretaceous .
Naming and history
The "Tithon" was introduced in 1865 by Albert Oppel . The name of the Tithonium goes back to Tithonos , a figure from Greek mythology . Tithonos was the husband of Eos , the goddess of the dawn, comparable to Tithonium, which is closely connected with the beginning of the Cretaceous period.
Definition and GSSP
The stage begins with the ammonite zone of the Hybonoticeras hybonotum and ends with the onset of the ammonite Berriasella jacobi . A GSSP (global type locality and type profile) has not yet been defined.
In the tithonium area, tithonium is subdivided into seven ammonite biozones:
- Micracanthoceras micranthum
- Micracanthoceras ponti / Burckardticeras peroni
- Semiformiceras fallauxi
- Semiformiceras semiforme
- Semiformiceras darwini
- Hybonoticeras hybonotum
There is a further subdivision of the level into a lower, middle and upper Tithonium, the latter corresponds to the Portlandian in England.
In the area of the marine deposits of the Tethys , the Tithon is formed as a calcareous facies with a typical cephalopod fauna. The fossils of the "primeval bird" Archeopteryx originate from the Tithonium of Germany ( Solnhofen limestone ) and are thus the oldest geological evidence of the evolution of birds .
- Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2005 ISBN 978-0-521-78673-7
- Hans Murawski & Wilhelm Meyer: Geological dictionary . 10., rework. u. exp. Ed., 278, Enke Verlag, Stuttgart 1998 ISBN 3-432-84100-0 .
- Albert Oppel: The Tithonic Floor. Journal of the German Geological Society, 1865: 535–558, Berlin 1865.
- German Stratigraphic Commission, Manfred Menning (Hrsg.): Stratigraphische Tisch von Deutschland 2002 . Potsdam 2002, ISBN 3-00-010197-7 (1 sheet, Stratigraphie.de [PDF; 6.6 MB ]).
- Commission for the paleontological and stratigraphic research of Austria of the Austrian Academy of Sciences (Ed.): The Stratigraphic Table of Austria (sedimentary layer sequences). Vienna 2004 (PDF; 376 KB)
- International Chronostratigraphic Chart 2012 (PDF)