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
M. Kretzoi. 1942. Necroteuthis n. g. (Ceph. Dibr., Necroteuthidae N. F.) aus dem Oligozän von Budapest und das system der Dibranchiata. Földtani Közlöny 72:125-238 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

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 126679 collections

Show more time

Show linear time

International Chronostratigraphic Timescale			Ordovician of North America					Cambrian of Kazakhstan	Ordovician of Britain				Ordovician of Australia	Ten Million Year Bins	Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian					Ashgill	Hirnantian			Bolindian	Ordovician 5	Kosovian				443.8
		Katian		Gamachian						Rawtheyan					Kralodvorian	Bohdalec †			445.2
				Richmondian						Rawtheyan									446 *
										Cautleyan									448.9 *
										Cautleyan			Eastonian						449 *
										Pusgillian									449.3 *
									Caradoc	Streffordian	Onnian †								449.6 *
															Berounian				449.7 *
				Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian														449.8 *
				Edenian															450.4 *
			Mohawkian	Chatfieldian															451.1 *
										Cheneyan									451.5 *
										Cheneyan			Gisbornian						452 *
										Burrellian									452.7 *
		Sandbian												Ordovician 4					453
											Actonian †								453.2 *
				Turinian							Actonian †								453.7 *
											Marshbrookian †	Woolstonian †							454.2 *
											Longvillian †								455.2 *
																	Zahorany †/Vinice	Letna †	456.2 *
										Aurelucian									456.8 *
			Whiterockian		Canadian †	Chazyan †/Marmor													457 *
											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 *
				Rangerian									Castlemainian						469.1 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †						Chewtonian						470
										Whitlandian			Chewtonian						471.1 *
													Bendigonian						471.8 *
													Lancefieldian						473.5 *
				Tulean															473.9 *
										Moridunian									474.3 *
		Tremadocian						Ungurian	Tremadoc	Migneintian				Ordovician 1	Tremadocian				477.7
				Stairsian						Migneintian									480.3 *
				Stairsian						Cressagian									480.8 *
				Skullrockian/Demingian															482 *
													Warendian						482.8 *
													Warendian						485 *
																			485.4
																			487.5