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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. 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 126606 collections

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International Chronostratigraphic Timescale			Ordovician of Britain				Cambrian of Siberia	Ordovician of the Baltic				Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Ashgill	Hirnantian				Harju	Porkuni			Kosovian				443.8
		Katian		Rawtheyan					Pirgu			Kralodvorian	Bohdalec †			445.2
				Cautleyan												448.9 *
				Pusgillian												449.3 *
			Caradoc	Streffordian	Onnian †				Vormsi							449.6 *
									Vormsi			Berounian				449.7 *
									Nabala	Johvi †						450 *
								Viru	Rakvere							450.6 *
				Cheneyan					Rakvere							451.5 *
				Cheneyan					Oandu							452 *
				Burrellian					Oandu							452.7 *
		Sandbian							Keila	Idavere †						453
					Actonian †				Keila							453.2 *
					Actonian †				Haljala							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 *
									Lasnamagi			Dobrotivian				458.9 *
									Lasnamagi			Oretanian				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 *
				Whitlandian					Hunneberg							473.7 *
				Moridunian												474.3 *
		Tremadocian	Tremadoc	Migneintian								Tremadocian				477.7
				Cressagian												480.8 *
									Varangu							481.3 *
									Pakerort							482.2 *
							Mansian †									483.55 *
							Mansian †									485 *
																485.4 *
																486.3
																486.5