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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 126701 collections

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International Chronostratigraphic Timescale			Ordovician of Australia	Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Bolindian	Kosovian				443.8
		Katian	Bolindian	Kralodvorian	Bohdalec †			445.2
			Eastonian	Kralodvorian				449 *
			Eastonian	Berounian				449.7 *
			Gisbornian					452 *
		Sandbian						453
						Zahorany †/Vinice	Letna †	456.2 *
					Liben †			458 *
	Middle Ordovician	Darriwilian	Darriwilian					458.4
				Dobrotivian				458.5 *
				Oretanian				459.7 *
					Sarka †			461.7 *
		Dapingian	Yapeenian		Klabava †			467.3
			Yapeenian	Arenigian				468
			Castlemainian					468.5 *
	Early Ordovician	Floian	Chewtonian					470
			Bendigonian					471.8 *
			Lancefieldian					473.5 *
		Tremadocian	Lancefieldian	Tremadocian				477.7
		Tremadocian	Warendian	Tremadocian				482.8 *
								485.4