Wuchiapingian

System/
Period		 Series/
Epoch		 Stage/
Age		 Age (Ma)
Triassic Lower/
Early		 Induan younger
Permian Lopingian Changhsingian 252.2–254.1
Wuchiapingian 254.1–259.8
Guadalupian Capitanian 259.8–265.1
Wordian 265.1–268.8
Roadian 268.8–272.3
Cisuralian Kungurian 272.3–283.5
Artinskian 283.5–290.1
Sakmarian 290.1–295.0
Asselian 295.0–298.9
Carboniferous Pennsylvanian Gzhelian older
Subdivision of the Permian system
according to the ICS (Geologic Time Scale 2013).[1]

In the geologic timescale, the Wuchiapingian or Wujiapingian (from Chinese: 吴家坪; pinyin: Wújiāpíng; literally: "Wu Family Flatland"" in the Liangshan area of Hanzhong, Shaanxi Province[2]) is an age or stage of the Permian. It is also the lower or earlier of two subdivisions of the Lopingian epoch or series. The Wuchiapingian spans the time between 259.8 ± 0.4 and 254.14 ± 0.07 million years ago (Ma). It was preceded by the Capitanian and followed by the Changhsingian.[3]

Regional stages with which the Wuchiapingian is coeval or overlaps include the Djulfian or Dzhulfian, Longtanian, Rustlerian, Saladoan, and Castilian.[4]

Stratigraphic definitions

The Wuchiapingian was first used in 1962, when the Lopingian series of southwestern China was divided in the Changhsingian and Wuchiapingian formations.[5] In 1973 the Wuchiapingian was first used as a chronostratigraphic unit (i.e. a stage, as opposed to a formation, which is a lithostratigraphic unit).[6]

The base of the Wuchiapingian stage is defined as the place in the stratigraphic record where the conodont species Clarkina postbitteri postbitteri first appears. A global reference profile for this boundary (a GSSP) is located near Laibin in the Chinese province of Guangxi.[7]

The top of the Wuchiapingian (the base of the Changhsingian) is at the first appearance of conodont species Clarkina wangi.

The Wuchiapingian contains two ammonite biozones: that of the genus Araxoceras and that of the genera Roadoceras and Doulingoceras.

Biodiversity

An extinction pulse occurred during the Wuchiapingian; faunas were recovering when another larger extinction pulse, the Permian-Triassic Extinction Event devastated life.[8]

References

Notes

  1. ↑ "Chronostratigraphic chart 2013". ICS. Retrieved 27 March 2013.
  2. ↑ "陕西汉中梁山吴家坪灰岩的再研究 (Restudies on the Wujiaping Limestone Liangshan of Hanzhong, Shaanxi)". Retrieved 29 November 2012.
  3. ↑ See Gradstein et al. (2004) for a detailed geologic timescale
  4. ↑ "Wuchiapingian". GeoWhen Database, International Commission on Stratigraphy (ICS). Retrieved 4 March 2010.
  5. ↑ By Sheng (1962)
  6. ↑ The Wuchiapingian stage was first used by Kanmera & Nakazawa (1973)
  7. ↑ The GSSP for the Wuchiapingian stage was established by Jin et al. (2006)
  8. ↑ Sahney, S. and Benton, M.J. (2008). "Recovery from the most profound mass extinction of all time" (PDF). Proceedings of the Royal Society: Biological 275 (1636): 759–65. doi:10.1098/rspb.2007.1370. PMC 2596898. PMID 18198148.

Literature

External links