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
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 126778 collections

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International Chronostratigraphic Timescale			Ordovician of North America					Ordovician of the Baltic				Ordovician of Australia
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian				Harju	Porkuni			Bolindian	443.8
		Katian		Gamachian					Pirgu				445.2
				Richmondian									446 *
												Eastonian	449 *
									Vormsi				449.6 *
				Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian				Vormsi				449.8 *
				Maysvillian					Nabala	Johvi †			450 *
				Edenian					Nabala				450.4 *
				Edenian				Viru	Rakvere				450.6 *
			Mohawkian	Chatfieldian					Rakvere				451.1 *
									Oandu			Gisbornian	452 *
		Sandbian							Keila	Idavere †			453
				Turinian					Keila				453.7 *
									Haljala				453.9
									Kukruse				456.4 *
			Whiterockian		Canadian †	Chazyan †/Marmor			Kukruse				457 *
									Uhaku	Aluoja †			457.5 *
	Middle Ordovician	Darriwilian							Uhaku			Darriwilian	458.4
									Lasnamagi				458.9 *
									Aseri				460.4 *
								Oeland	Kunda				462.9 *
									Kunda	Valaste †/Hunderum			464.3 *
									Volkhov		Langevoja †/Vaana/Saka		467.1 *
		Dapingian										Yapeenian	467.3
												Castlemainian	468.5 *
				Rangerian									469.1 *
				Rangerian					Billingen				469.3 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †					Chewtonian	470
										Latorp †		Chewtonian	470.1 *
												Bendigonian	471.8 *
												Lancefieldian	473.5 *
									Hunneberg				473.7 *
				Tulean									473.9 *
		Tremadocian		Tulean									477.7
				Stairsian									480.3 *
				Stairsian					Varangu				481.3 *
				Skullrockian/Demingian					Varangu				482 *
									Pakerort				482.2 *
									Pakerort			Warendian	482.8 *
													485.4 *
													486.3
													486.5
													487.5