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
M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 view
M. Freudenthal. 2006. Mammal Paleogene zones. personal communication 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
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 126764 collections

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International Chronostratigraphic Timescale			Ordovician of Ibero-Bohemia				Ordovician of North America
Ordovician	Late Ordovician	Hirnantian	Kosovian				Cincinnatian	Gamachian				443.8
		Katian	Kralodvorian	Bohdalec †				Gamachian				445.2
			Kralodvorian					Richmondian				446 *
			Berounian					Richmondian				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 *
					Zahorany †/Vinice	Letna †		Turinian				456.2 *
					Zahorany †/Vinice		Whiterockian		Canadian †	Chazyan †/Marmor		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	Tremadocian					Tulean				477.7
								Stairsian				480.3 *
								Skullrockian/Demingian				482 *
												485.4
												487.5