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
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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 North America					Ordovician of China			Ordovician of Australia	Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian				Hirnantian	Xiaoxita †/Shikou	Wufeng †	Bolindian	Kosovian				443.8
		Katian		Gamachian				Chientangkiangian				Kralodvorian	Bohdalec †			445.2
				Richmondian												446 *
											Eastonian					449 *
								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 *
											Gisbornian					452 *
		Sandbian														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		Darriwilian					458.4
												Dobrotivian				458.5 *
												Oretanian				459.7 *
													Sarka †			461.7 *
									Hunjiang †	Dawan †/Daobaowan/Ningkuo			Sarka †			466.3 *
		Dapingian						Dapingian			Yapeenian		Klabava †			467.3
											Yapeenian	Arenigian				468
											Castlemainian					468.5 *
				Rangerian							Castlemainian					469.1 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †	Yiyangian			Chewtonian					470
											Bendigonian					471.8 *
											Lancefieldian					473.5 *
				Tulean												473.9 *
		Tremadocian						Xinchangian				Tremadocian				477.7
										Lianghekou †						477.9 *
				Stairsian												480.3 *
				Skullrockian/Demingian												482 *
				Skullrockian/Demingian							Warendian					482.8 *
																485.4
																487.5