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
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
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

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 126662 collections

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International Chronostratigraphic Timescale			Ordovician of Britain				Ordovician of Australia	Ten Million Year Bins	Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Ashgill	Hirnantian			Bolindian	Ordovician 5	Kosovian				443.8
		Katian		Rawtheyan					Kralodvorian	Bohdalec †			445.2
				Cautleyan									448.9 *
				Cautleyan			Eastonian						449 *
				Pusgillian									449.3 *
			Caradoc	Streffordian	Onnian †								449.6 *
				Streffordian					Berounian				449.7 *
				Cheneyan									451.5 *
				Cheneyan			Gisbornian						452 *
				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 *
					Soudleyan †/Harnagian/Costonian					Liben †			458 *
	Middle Ordovician	Darriwilian	Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			Darriwilian	Ordovician 3					458.4
									Dobrotivian				458.5 *
									Oretanian				459.7 *
				Abereiddian/Early Llanvirn									461.3 *
										Sarka †			461.7 *
		Dapingian					Yapeenian	Ordovician 2		Klabava †			467.3
									Arenigian				468
			Arenig	Fennian									468.4 *
							Castlemainian						468.5 *
	Early Ordovician	Floian					Chewtonian						470
				Whitlandian			Chewtonian						471.1 *
							Bendigonian						471.8 *
							Lancefieldian						473.5 *
				Moridunian									474.3 *
		Tremadocian	Tremadoc	Migneintian				Ordovician 1	Tremadocian				477.7
				Cressagian									480.8 *
				Cressagian			Warendian						482.8 *
							Warendian						485 *
													485.4