PBDB Interval

International Chronostratigraphic Timescale

The interval definitions in this timescale are derived from the following sources:

K. M. Cohen, S.C. Finney, P.L. Gibbard and J.-X. Fan. 2023. The ICS International Chronostratigraphic Chart v2023/09. view
J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 view
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
W. B. Harland, R. L. Armstrong, A. V. Cox, L. E. Craig, A. G. Smith and D. G. Smith. 1990. A Geologic Time Scale 1989. view
D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. view
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 view

There are 59 timescales which overlap this one. show

Interval boundaries marked with * have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 126585 collections

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International Chronostratigraphic Timescale			Cambrian of Siberia	Ordovician of Britain				Ordovician of China			Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian		Ashgill	Hirnantian			Hirnantian	Xiaoxita †/Shikou	Wufeng †	Kosovian				443.8
		Katian			Rawtheyan			Chientangkiangian			Kralodvorian	Bohdalec †			445.2
					Cautleyan										448.9 *
					Pusgillian										449.3 *
					Pusgillian			Neichianshanian/Hanjiang							449.5
				Caradoc	Streffordian	Onnian †									449.6 *
					Streffordian						Berounian				449.7 *
					Cheneyan										451.5 *
					Burrellian										452.7 *
		Sandbian													453
						Actonian †									453.2 *
						Marshbrookian †	Woolstonian †								454.2 *
						Longvillian †									455.2 *
													Zahorany †/Vinice	Letna †	456.2 *
					Aurelucian										456.8 *
						Soudleyan †/Harnagian/Costonian									457.4 *
						Soudleyan †/Harnagian/Costonian						Liben †			458 *
	Middle Ordovician	Darriwilian		Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			Darriwilian	Guniu †/Hulo						458.4
											Dobrotivian				458.5 *
											Oretanian				459.7 *
					Abereiddian/Early Llanvirn										461.3 *
												Sarka †			461.7 *
									Hunjiang †	Dawan †/Daobaowan/Ningkuo		Sarka †			466.3 *
		Dapingian						Dapingian				Klabava †			467.3
											Arenigian				468
				Arenig	Fennian										468.4 *
	Early Ordovician	Floian			Fennian			Yiyangian							470
					Whitlandian										471.1 *
					Moridunian										474.3 *
		Tremadocian		Tremadoc	Migneintian			Xinchangian			Tremadocian				477.7
					Migneintian					Lianghekou †					477.9 *
					Cressagian										480.8 *
			Mansian †		Cressagian										483.55 *
			Mansian †												485 *
															485.4