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
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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
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

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 126710 collections

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International Chronostratigraphic Timescale			Ordovician of China			Cambrian of Kazakhstan	Ordovician of North America					Ten Million Year Bins	Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Hirnantian	Xiaoxita †/Shikou	Wufeng †		Cincinnatian	Gamachian				Ordovician 5	Kosovian				443.8
		Katian	Chientangkiangian					Gamachian					Kralodvorian	Bohdalec †			445.2
			Chientangkiangian					Richmondian									446 *
			Neichianshanian/Hanjiang														449.5
													Berounian				449.7 *
								Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian								449.8 *
								Edenian									450.4 *
							Mohawkian	Chatfieldian									451.1 *
		Sandbian						Chatfieldian				Ordovician 4					453
								Turinian									453.7 *
								Turinian							Zahorany †/Vinice	Letna †	456.2 *
							Whiterockian		Canadian †	Chazyan †/Marmor					Zahorany †/Vinice		457 *
														Liben †			458 *
	Middle Ordovician	Darriwilian	Darriwilian	Guniu †/Hulo								Ordovician 3					458.4
													Dobrotivian				458.5 *
													Oretanian				459.7 *
														Sarka †			461.7 *
				Hunjiang †	Dawan †/Daobaowan/Ningkuo									Sarka †			466.3 *
		Dapingian	Dapingian									Ordovician 2		Klabava †			467.3
													Arenigian				468
								Rangerian									469.1 *
	Early Ordovician	Floian	Yiyangian				Ibexian	Blackhillsian		Jeffersonian †	Cassinian †						470
		Floian	Yiyangian					Tulean									473.9 *
		Tremadocian	Xinchangian			Ungurian						Ordovician 1	Tremadocian				477.7
					Lianghekou †												477.9 *
								Stairsian									480.3 *
								Skullrockian/Demingian									482 *
																	485.4
																	487.5