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
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

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

Show more time

Show linear time

International Chronostratigraphic Timescale			Cambrian of Siberia	Ordovician of Australia	Ordovician of Britain				Ten Million Year Bins	Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian		Bolindian	Ashgill	Hirnantian			Ordovician 5	Kosovian				443.8
		Katian				Rawtheyan				Kralodvorian	Bohdalec †			445.2
						Cautleyan								448.9 *
				Eastonian		Cautleyan								449 *
						Pusgillian								449.3 *
					Caradoc	Streffordian	Onnian †							449.6 *
						Streffordian				Berounian				449.7 *
						Cheneyan								451.5 *
				Gisbornian		Cheneyan								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		Darriwilian	Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			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
				Chewtonian		Whitlandian								471.1 *
				Bendigonian										471.8 *
				Lancefieldian										473.5 *
						Moridunian								474.3 *
		Tremadocian			Tremadoc	Migneintian			Ordovician 1	Tremadocian				477.7
						Cressagian								480.8 *
				Warendian										482.8 *
			Mansian †											483.55 *
			Mansian †											485 *
														485.4