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
J. Palfy, P. L. Smith, and J. K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time scale for the Jurassic. Canadian Journal of Earth Sciences 37(6):923-944 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 126654 collections

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International Chronostratigraphic Timescale			Ordovician of North America					Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian				Kosovian				443.8
		Katian		Gamachian				Kralodvorian	Bohdalec †			445.2
				Richmondian				Kralodvorian				446 *
				Richmondian				Berounian				449.7 *
				Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian							449.8 *
				Edenian								450.4 *
			Mohawkian	Chatfieldian								451.1 *
		Sandbian		Chatfieldian								453
				Turinian								453.7 *
				Turinian						Zahorany †/Vinice	Letna †	456.2 *
			Whiterockian		Canadian †	Chazyan †/Marmor				Zahorany †/Vinice		457 *
									Liben †			458 *
	Middle Ordovician	Darriwilian										458.4
								Dobrotivian				458.5 *
								Oretanian				459.7 *
									Sarka †			461.7 *
		Dapingian							Klabava †			467.3
								Arenigian				468
				Rangerian								469.1 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †					470
		Floian		Tulean								473.9 *
		Tremadocian		Tulean				Tremadocian				477.7
				Stairsian								480.3 *
				Skullrockian/Demingian								482 *
												485.4
												487.5