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
D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. 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
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 126662 collections

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International Chronostratigraphic Timescale			Cambrian of Kazakhstan	Cambrian of Siberia	Ordovician of the Baltic				Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian			Harju	Porkuni			Kosovian				443.8
		Katian				Pirgu			Kralodvorian	Bohdalec †			445.2
						Vormsi			Kralodvorian				449.6 *
						Vormsi			Berounian				449.7 *
						Nabala	Johvi †						450 *
					Viru	Rakvere							450.6 *
						Oandu							452 *
		Sandbian				Keila	Idavere †						453
						Haljala							453.9
						Haljala					Zahorany †/Vinice	Letna †	456.2 *
						Kukruse							456.4 *
						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
						Billingen							469.3 *
	Early Ordovician	Floian											470
							Latorp †						470.1 *
						Hunneberg							473.7 *
		Tremadocian	Ungurian			Hunneberg			Tremadocian				477.7
						Varangu							481.3 *
						Pakerort							482.2 *
				Mansian †		Pakerort							483.55 *
													485.4 *
													486.3
													486.5