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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
F. M. Gradstein, F. P. Agterberg, J. G. Ogg, J. Hardenbol, P. Van Veen, J. Thierry, and Z. Huang. 1995. A Triassic, Jurassic, and Cretaceous time scale. SEPM Special Publication 54 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

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 127245 collections

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International Chronostratigraphic Timescale			Ordovician of Ibero-Bohemia				Ordovician of the Baltic				Ordovician of Britain
Ordovician	Late Ordovician	Hirnantian	Kosovian				Harju	Porkuni			Ashgill	Hirnantian			443.8
		Katian	Kralodvorian	Bohdalec †				Pirgu				Rawtheyan			445.2
												Cautleyan			448.9 *
												Pusgillian			449.3 *
								Vormsi			Caradoc	Streffordian	Onnian †		449.6 *
			Berounian					Vormsi							449.7 *
								Nabala	Johvi †						450 *
							Viru	Rakvere							450.6 *
								Rakvere				Cheneyan			451.5 *
								Oandu				Cheneyan			452 *
								Oandu				Burrellian			452.7 *
		Sandbian						Keila	Idavere †						453
								Keila					Actonian †		453.2 *
								Haljala					Actonian †		453.9
													Marshbrookian †	Woolstonian †	454.2 *
													Longvillian †		455.2 *
					Zahorany †/Vinice	Letna †									456.2 *
								Kukruse							456.4 *
												Aurelucian			456.8 *
													Soudleyan †/Harnagian/Costonian		457.4 *
								Uhaku	Aluoja †						457.5 *
				Liben †											458 *
	Middle Ordovician	Darriwilian									Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			458.4
			Dobrotivian												458.5 *
			Dobrotivian					Lasnamagi							458.9 *
			Oretanian					Lasnamagi							459.7 *
								Aseri							460.4 *
												Abereiddian/Early Llanvirn			461.3 *
				Sarka †											461.7 *
							Oeland	Kunda							462.9 *
								Kunda	Valaste †/Hunderum						464.3 *
								Volkhov		Langevoja †/Vaana/Saka					467.1 *
		Dapingian		Klabava †											467.3
			Arenigian												468
											Arenig	Fennian			468.4 *
								Billingen							469.3 *
	Early Ordovician	Floian													470
									Latorp †						470.1 *
												Whitlandian			471.1 *
								Hunneberg				Whitlandian			473.7 *
												Moridunian			474.3 *
		Tremadocian	Tremadocian								Tremadoc	Migneintian			477.7
												Cressagian			480.8 *
								Varangu							481.3 *
								Pakerort							482.2 *
								Pakerort							485 *
															485.4 *
															486.3
															486.5