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
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
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 126700 collections

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International Chronostratigraphic Timescale			Ordovician of the Baltic				Ordovician of North America					Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Harju	Porkuni			Cincinnatian	Gamachian				Kosovian				443.8
		Katian		Pirgu				Gamachian				Kralodvorian	Bohdalec †			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						Tulean				Tremadocian				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