Mississippium
| system | Subsystem | step | ≈ age ( mya ) |
|---|---|---|---|
| higher | higher | higher | younger |
| Carbon | Pennsylvania | Gzhelium | 298.9 ⬍ 303.7 |
| Kasimovium | 303.7 ⬍ 307 |
||
| Moskovium | 307 ⬍ 315.2 |
||
| Bashkirium | 315.2 ⬍ 323.2 |
||
| Mississippium | Serpukhovium | 323.2 ⬍ 330.9 |
|
| Visa | 330.9 ⬍ 346.7 |
||
| Tournaisium | 346.7 ⬍ 358.9 |
||
| deeper | deeper | deeper | older |
The Mississippium (formerly Lower Carboniferous ) is a chronostratigraphic subsystem of the Carboniferous in geological history . It began geochronologically about 358.9 million years ago and ended about 323.2 million years ago. It follows the Upper Devonian series and is overlaid by the Pennsylvania subsystem of Carbon.
Naming and history
The name Mississippium was proposed by the American geologist Alexander Winchell in 1869 and named after the Mississippi . In America it comprises layers of limestone, in 1891 the Mississippium was contrasted by HS Williams with the coal-rich layers of the Pennsylvania . However, this division is not identical to the earlier division of carbon in Europe. In 2004 it was ratified by the International Commission on Stratigraphy (ICS) and the International Union of Geological Sciences (IUGS) as a subsystem of carbon.
Definition and GSSP
The beginning of the Mississippian (and carbon) is determined by the first appearance of Conodonten -type Siphonodella sulcata within the line of development of Siphonodella praesulcata to Siphonodella sulcata defined. The series ends at the time of the first appearance of the Conodont Art Declinognathodus nodiliferus . The GSSP (official reference profile of the International Commission for Stratigraphy) of the Mississippian (and Tournaisium and Carboniferous) is the La Serre profile in the southeastern Montagne Noire ( France ). It is a cut about 80 cm deep on the southern slope of Mount La Serre, about 125 m south of the summit (252 m), about 525 m east of Maison La Roquette, in the area of Cabrières , 2.5 km northeast of the location Fontès ( Hérault ): 43 ° 33 '19.8 " N , 3 ° 21' 26.3" O
Breakdown
Originally, the Mississippium in America was divided into the regional Waverley and Tennessee levels. In line with the international level structure, it is now divided into three series (Lower, Middle and Upper Mississippium), each containing only one level.
-
System : carbon (358.9–298.9 mya )
- Subsystem : Pennsylvania (formerly Upper Carboniferous) (323.2–298.9 mya)
- Subsystem: Mississippium (formerly Lower Carboniferous) (358.9–323.2 mya)
- Series: Upper Mississippium (330.9–323.2 mya)
- Stage: Serpukhovium (330.9–323.2 mya)
- Series: Middle Mississippium (346.7-330.9 mya)
- Stage: Viseum (346.7 to 330.9 mya)
- Series: Untermissippium (358.9–346.7 mya)
- Stage: Tournaisium (358.9–346.7 mya)
- Series: Upper Mississippium (330.9–323.2 mya)
Regional breakdown
In Europe, carbon was divided into dinantium ("lower carbon") and silesium ("upper carbon"). The earlier demarcation of the Lower Carboniferous / Upper Carboniferous in Europe does not coincide with today's international demarcation. The upper limit of the Silesium does not coincide with the current international Carbon-Permian limit either.
Paleogeography
Baltica (essentially Europe) and Laurentia (essentially North America) were merged into a single continent called Laurussia . During the Mississippium, the southern continent of Gondwana drifted towards Laurussia and collided with Laurussia in Pennsylvania.
literature
- Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2004, ISBN 978-0-521-78673-7 .
- E. Paproth, R. Feist and G. Flaijs: Decision on the Devonian-Carboniferous boundary stratotype. In: Episodes. 14 (4): 331-336, Beijing 1991.
Web links
- German Stratigraphic Commission (Ed.): Stratigraphische Tisch von Deutschland 2002 . Potsdam 2002 ISBN 3-00-010197-7 - PDF; 6.57 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