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
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
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 127243 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