Callovium
| system | series | step | ≈ age ( mya ) |
|---|---|---|---|
| higher | higher | higher | younger |
| law | Upper Jurassic | Tithonium | 145 ⬍ 152.1 |
| Kimmeridgium | 152.1 ⬍ 157.3 |
||
| Oxfordium | 157.3 ⬍ 163.5 |
||
| Middle Jurassic | Callovium | 163.5 ⬍ 166.1 |
|
| Bathonium | 166.1 ⬍ 168.3 |
||
| Bajocium | 168.3 ⬍ 170.3 |
||
| Aalenium | 170.3 ⬍ 174.1 |
||
| Lower Jurassic | Toarcium | 174.1 ⬍ 182.7 |
|
| Pliensbachium | 182.7 ⬍ 190.8 |
||
| Sinemurium | 190.8 ⬍ 199.3 |
||
| Hettangium | 199.3 ⬍ 201.3 |
||
| deeper | deeper | deeper | older |
The Callovium (in German often shortened to Callov , more rarely also Callovien) is the highest chronostratigraphic level of the Middle Jurassic series of the Jura in geological history . The callovian began geochronologically about 166.1 million years ago and ended about 163.5 million years ago. It follows the Bathonium and is replaced by the Oxfordium , the lowest level of the Upper Jurassic .
Naming and history
The term "Callovium" was introduced by Alcide d'Orbigny in 1852. It is the Latinized form of Kellaways , a town in Wiltshire , England (near Chippenham ). In England the term "Kelloway rock" was also used for this level.
Definition and GSSP
The stage begins with the first appearance of the ammonite genus Kepplerites ( Macrocephalites- herreyi -Zone) in the fossil record . It ends with the first appearance of the ammonite species Brightia thuouxensis at the base of the first ammonite zone of the Oxfordium from the Upper Jurassic. A GSSP (type locality and type profile) has not yet been defined.
Subdivision of the Callovium
The Callovian is in Tethysbereich in six ammonite - biozones divided:
- Quenstedtoceras lamberti
- Peltoceras athleta
- Erymnoceras coronatum
- Reineckeia anceps
- Macrocephalites gracilis
- Bullatimorphites bullatus
The English Oxford Clay is divided into seven zones:
- Quenstedtoceras lamberti
- Peltoceras athleta
- Erymnoceras coronatum
- Kosmoceras Jason
- Sigaloceras calloviense
- Proplanulites koenigi
- Macrocephalites herreyi
The level is divided into three sub-levels: lower calcium, middle calcium, and upper calcium.
Individual evidence
literature
- Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2004, ISBN 978-0-521-78673-7 PDF
- Hans Murawski & Wilhelm Meyer: Geological dictionary . 10., rework. u. exp. Ed., 278, Enke Verlag, Stuttgart 1998, ISBN 3-432-84100-0 .
- Alcide d´Orbigny: Paléontologie française. 1. Terrains oolitiques or jurassiques. 642 pp., Bertrand, Paris 1842
Web links
- 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 ]).
- bib.telegrafenberg.de . German Stratigraphic Commission, Manfred Menning, Hendrich, Andreas (Hrsg.): Stratigraphic Table of Germany 2016 , ISBN 978-3-9816597-7-1 (PDF)
- 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; 1.77 MB)
- International Chronostratigraphic Chart 2013 (PDF)