System	Series	Stage	Age (Ma)
Triassic	Lower	Induan	younger
Permian	Lopingian	Changhsingian	251.0–253.8
		Wuchiapingian	253.8–260.4
	Guadalupian	Capitanian	260.4–265.8
		Wordian	265.8–268.0
		Roadian	268.0–270.6
	Cisuralian	Kungurian	270.6–275.6
		Artinskian	275.6–284.4
		Sakmarian	284.4–294.6
		Asselian	294.6–299.0
Carboniferous	Pennsylvanian	Gzhelian	older
Subdivision of the Permian system according to the IUGS, as of July 2009.

In the geologic timescale, the Wuchiapingian (also: Wujiapingian) 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 260.4 ± 0.7 and 253.8 ± 0.7 million years ago (Ma). It was preceded by the Capitanian and followed by the Changhsingian.^[1]

Regional stages with which the Wuchiapingian is coeval or overlaps include the Djulfian or Dzhulfian, Longtanian, Rustlerian, Saladoan, Kazanian and Castile.

Contents 1 Stratigraphic definitions 2 References 2.1 Notes 2.2 Literature 2.3 External links

[edit] Stratigraphic definitions

The Wuchiapingian was first used in 1962, when the Lopingian series of southwestern China was divided in the Changhsingian and Wuchiapingian Formations.^[2] 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).^[3]

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.^[4]

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.

[edit] References

[edit] Notes

1. ^ See Gradstein et al. (2004) for a detailed geologic timescale
2. ^ By Sheng (1962)
3. ^ The Wuchiapingian stage was first used by Kenmara & Makazawa (1973)
4. ^ The GSSP for the Wuchiapingian stage was established by Jin et al. (2006)

[edit] Literature

• Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press
• Jin, Y.; Shen, S.; Henderson, C.M.; Wang, X.; Wang, W.; Wang, Y.; Cao, C. & Shang, Q.; 2006: The Global Stratotype Section and Point (GSSP) for the boundary between the Capitanian and Wuchiapingian Stage (Permian)., Episodes 29(4), p. 253-262.

[edit] External links

• GeoWhen Database - Wuchiapingian
• Upper Paleozoic stratigraphic chart at the website of the subcommission for stratigraphic information of the ICS