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
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
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 126662 collections

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International Chronostratigraphic Timescale			Ordovician of the Baltic				Ordovician of Ibero-Bohemia				Ordovician of North America
Ordovician	Late Ordovician	Hirnantian	Harju	Porkuni			Kosovian				Cincinnatian	Gamachian				443.8
		Katian		Pirgu			Kralodvorian	Bohdalec †				Gamachian				445.2
				Pirgu								Richmondian				446 *
				Vormsi												449.6 *
							Berounian									449.7 *
												Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian			449.8 *
				Nabala	Johvi †							Maysvillian				450 *
				Nabala								Edenian				450.4 *
			Viru	Rakvere								Edenian				450.6 *
				Rakvere							Mohawkian	Chatfieldian				451.1 *
				Oandu												452 *
		Sandbian		Keila	Idavere †											453
				Keila								Turinian				453.7 *
				Haljala												453.9
				Haljala					Zahorany †/Vinice	Letna †						456.2 *
				Kukruse												456.4 *
				Kukruse							Whiterockian		Canadian †	Chazyan †/Marmor		457 *
				Uhaku	Aluoja †											457.5 *
								Liben †								458 *
	Middle Ordovician	Darriwilian														458.4
							Dobrotivian									458.5 *
				Lasnamagi			Dobrotivian									458.9 *
				Lasnamagi			Oretanian									459.7 *
				Aseri												460.4 *
				Aseri				Sarka †								461.7 *
			Oeland	Kunda												462.9 *
				Kunda	Valaste †/Hunderum											464.3 *
				Volkhov		Langevoja †/Vaana/Saka										467.1 *
		Dapingian						Klabava †								467.3
							Arenigian									468
												Rangerian				469.1 *
				Billingen								Rangerian				469.3 *
	Early Ordovician	Floian									Ibexian	Blackhillsian		Jeffersonian †	Cassinian †	470
					Latorp †											470.1 *
				Hunneberg												473.7 *
												Tulean				473.9 *
		Tremadocian					Tremadocian					Tulean				477.7
												Stairsian				480.3 *
				Varangu								Stairsian				481.3 *
				Varangu								Skullrockian/Demingian				482 *
				Pakerort								Skullrockian/Demingian				482.2 *
																485.4 *
																486.3
																486.5
																487.5