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

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 126701 collections

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International Chronostratigraphic Timescale			Ordovician of the Baltic				Ordovician of Britain
Ordovician	Late Ordovician	Hirnantian	Harju	Porkuni			Ashgill	Hirnantian			443.8
		Katian		Pirgu				Rawtheyan			445.2
								Cautleyan			448.9 *
								Pusgillian			449.3 *
				Vormsi			Caradoc	Streffordian	Onnian †		449.6 *
				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 *
				Kukruse							456.4 *
								Aurelucian			456.8 *
									Soudleyan †/Harnagian/Costonian		457.4 *
				Uhaku	Aluoja †				Soudleyan †/Harnagian/Costonian		457.5 *
	Middle Ordovician	Darriwilian		Uhaku			Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			458.4
				Lasnamagi							458.9 *
				Aseri							460.4 *
				Aseri				Abereiddian/Early Llanvirn			461.3 *
			Oeland	Kunda							462.9 *
				Kunda	Valaste †/Hunderum						464.3 *
				Volkhov		Langevoja †/Vaana/Saka					467.1 *
		Dapingian									467.3
							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					Tremadoc	Migneintian			477.7
								Cressagian			480.8 *
				Varangu							481.3 *
				Pakerort							482.2 *
				Pakerort							485 *
											485.4 *
											486.3
											486.5