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
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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
A. G. Sennikov and V. K. Golubev. 2006. Vyazniki Biotic Assemblage of the Terminal Permian. Paleontological Journal 40(suppl. 4):S475-S481 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 127245 collections

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International Chronostratigraphic Timescale			Ordovician of China			Ten Million Year Bins	Ordovician of Ibero-Bohemia				Ordovician of Britain
Ordovician	Late Ordovician	Hirnantian	Hirnantian	Xiaoxita †/Shikou	Wufeng †	Ordovician 5	Kosovian				Ashgill	Hirnantian			443.8
		Katian	Chientangkiangian				Kralodvorian	Bohdalec †				Rawtheyan			445.2
												Cautleyan			448.9 *
												Pusgillian			449.3 *
			Neichianshanian/Hanjiang									Pusgillian			449.5
											Caradoc	Streffordian	Onnian †		449.6 *
							Berounian					Streffordian			449.7 *
												Cheneyan			451.5 *
												Burrellian			452.7 *
		Sandbian				Ordovician 4									453
													Actonian †		453.2 *
													Marshbrookian †	Woolstonian †	454.2 *
													Longvillian †		455.2 *
									Zahorany †/Vinice	Letna †					456.2 *
												Aurelucian			456.8 *
													Soudleyan †/Harnagian/Costonian		457.4 *
								Liben †					Soudleyan †/Harnagian/Costonian		458 *
	Middle Ordovician	Darriwilian	Darriwilian	Guniu †/Hulo		Ordovician 3					Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			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			Ordovician 2		Klabava †							467.3
							Arenigian								468
											Arenig	Fennian			468.4 *
	Early Ordovician	Floian	Yiyangian									Fennian			470
												Whitlandian			471.1 *
												Moridunian			474.3 *
		Tremadocian	Xinchangian			Ordovician 1	Tremadocian				Tremadoc	Migneintian			477.7
					Lianghekou †							Migneintian			477.9 *
												Cressagian			480.8 *
															485 *
															485.4