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
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
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
J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 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 126689 collections

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International Chronostratigraphic Timescale			Ordovician of Ibero-Bohemia				Ordovician of China			Ordovician of Australia	Ten Million Year Bins
Ordovician	Late Ordovician	Hirnantian	Kosovian				Hirnantian	Xiaoxita †/Shikou	Wufeng †	Bolindian	Ordovician 5	443.8
		Katian	Kralodvorian	Bohdalec †			Chientangkiangian			Bolindian		445.2
							Chientangkiangian			Eastonian		449 *
							Neichianshanian/Hanjiang					449.5
			Berounian									449.7 *
										Gisbornian		452 *
		Sandbian									Ordovician 4	453
					Zahorany †/Vinice	Letna †						456.2 *
				Liben †								458 *
	Middle Ordovician	Darriwilian					Darriwilian	Guniu †/Hulo		Darriwilian	Ordovician 3	458.4
			Dobrotivian									458.5 *
			Oretanian									459.7 *
				Sarka †								461.7 *
				Sarka †				Hunjiang †	Dawan †/Daobaowan/Ningkuo			466.3 *
		Dapingian		Klabava †			Dapingian			Yapeenian	Ordovician 2	467.3
			Arenigian							Yapeenian		468
										Castlemainian		468.5 *
	Early Ordovician	Floian					Yiyangian			Chewtonian		470
										Bendigonian		471.8 *
										Lancefieldian		473.5 *
		Tremadocian	Tremadocian				Xinchangian				Ordovician 1	477.7
									Lianghekou †			477.9 *
									Lianghekou †	Warendian		482.8 *
												485.4