Viséan
| Viséan | |
|---|---|
Romer's Gap |
Vertical axis scale: millions of years ago
Age
24°26′00″N 109°27′00″E / 24.4333°N 109.4500°E
- Ural mountains
- Nashui, Luodian County, Guizhou, China
The Visean, Viséan or Visian is an
age/stage.Name and definitions
The Viséan Stage was introduced by
Chesterian stages. In the Chinese regional time scale, it correlates with the lower and middle Tatangian series.[3]
The base of the Viséan Stage is at the first appearance of the
GSSP has been proposed in the Luzhai Formation near Penchong in the Chinese province of Guanxi.[4] The top (the base of the Serpukhovian and Namurian) is laid at the first appearance of the conodont Lochriea ziegleri,[5] or at the base of the biozone of goniatite Cravenoceras leion
.
Biota
The
Carboniferous-Earliest Permian Biodiversification Event began in the Viséan, coinciding with the start of the main phase of the Late Palaeozoic Ice Age.[6]
The late Viséan saw the widespread reappearance of
One of the tetrapods that lived during the Visean age was Westlothiana, a reptile-like amphibian. Though originally thought to be the earliest discovered amniote,[8] more recent research has cast doubt on this interpretation.[9]
Biostratigraphy
The Visean contains four conodont biozones:
In British stratigraphy, the Visean is subdivided into five substages. From youngest to oldest, these are:[10]
- Brigantian
- Asbian
- Holkerian
- Arundian
- Chadian (the lower part of this substage falls in the Tournaisian)
References
- ^ "Chart/Time Scale". www.stratigraphy.org. International Commission on Stratigraphy.
- ^ "International Chronostratigraphic Chart". International Commission on Stratigraphy. Retrieved 9 December 2012.
- ^ a b Menning, M.; Alekseev, A.S.; Chuvashov, B.I.; Davydov, V.I.; Devuyst, F.-X.; Forke, H.C.; Grunt, T.A.; Hance, L.; Heckel, P.H.; Izokh, N.G.; Jin, Y.-G.; Jones, P.J.; Kotlyar, G.V.; Kozur, H.W.; Nemyrovska, T.I.; Schneider, J.W.; Wang, X.-D.; Weddige, K.; Weyer, D. & Work, D.M.; 2006: Global time scale and regional stratigraphic reference scales of Central and West Europe, East Europe, Tethys, South China, and North America as used in the Devonian–Carboniferous–Permian Correlation Chart 2003 (DCP 2003), Palaeogeography, Palaeoclimatology, Palaeoecology 240 (1-2): pp 318–372.
- ^ Devuyst, F.X.; Hance, L.; Hou, H.-F.; Wu, X.; Tian, S.; Coen, M. & Sevastopulo, G.; 2003: A proposed Global Stratotype Section and Point for the base of the Visean Stage (Carboniferous): the Pengchong section, Guangxi, South China, Episodes 26 (2), pp 105–115
- ^ Nemyrovska, T.I.; 2005: Late Visean/early Serpukhovian conodont succession from the Triollo section, Palencia (Cantabrian Mountains, Spain), Scr. Geol. 129, pp 13–89
- . Retrieved 4 September 2022.
- S2CID 213966485. Retrieved 23 November 2022.
- S2CID 4358046.
- S2CID 129807712.
- ^ Heckel, P.H. & Clayton, G.; 2006: The Carboniferous system, use of the new official names for the subsystems, series and stages, Geologica Acta 4(3), pp 403–407.
Further reading
- Dumont, A.H.; 1832: Mémoire sur la constitution géologique de la province de Liège, Mémoires couronnés par l'Académie Royale des Sciences et Belles-Lettres de Bruxelles 8 (3), VII. (in French)
External links
- Upper and lower time scales for the Carboniferous at the website of the Norwegian network of offshore records of geology and stratigraphy
- Visean, Geowhen Database
- The Viséan age, www.palaeos.com
24°26′00″N 109°27′00″E / 24.4333°N 109.4500°E
