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
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, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
A. G. Sennikov and V. K. Golubev. 2006. Vyazniki Biotic Assemblage of the Terminal Permian. Paleontological Journal 40(suppl. 4):S475-S481 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 126848 collections

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International Chronostratigraphic Timescale			Ordovician of Britain				Ordovician of the Baltic				Ordovician of China
Ordovician	Late Ordovician	Hirnantian	Ashgill	Hirnantian			Harju	Porkuni			Hirnantian	Xiaoxita †/Shikou	Wufeng †	443.8
		Katian		Rawtheyan				Pirgu			Chientangkiangian			445.2
				Cautleyan										448.9 *
				Pusgillian										449.3 *
				Pusgillian							Neichianshanian/Hanjiang			449.5
			Caradoc	Streffordian	Onnian †			Vormsi						449.6 *
								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 *
								Kukruse						456.4 *
				Aurelucian										456.8 *
					Soudleyan †/Harnagian/Costonian									457.4 *
					Soudleyan †/Harnagian/Costonian			Uhaku	Aluoja †					457.5 *
	Middle Ordovician	Darriwilian	Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn				Uhaku			Darriwilian	Guniu †/Hulo		458.4
								Lasnamagi						458.9 *
								Aseri						460.4 *
				Abereiddian/Early Llanvirn				Aseri						461.3 *
							Oeland	Kunda						462.9 *
									Valaste †/Hunderum					464.3 *
												Hunjiang †	Dawan †/Daobaowan/Ningkuo	466.3 *
								Volkhov		Langevoja †/Vaana/Saka				467.1 *
		Dapingian									Dapingian			467.3
			Arenig	Fennian										468.4 *
								Billingen						469.3 *
	Early Ordovician	Floian									Yiyangian			470
									Latorp †					470.1 *
				Whitlandian										471.1 *
				Whitlandian				Hunneberg						473.7 *
				Moridunian										474.3 *
		Tremadocian	Tremadoc	Migneintian							Xinchangian			477.7
				Migneintian									Lianghekou †	477.9 *
				Cressagian										480.8 *
								Varangu						481.3 *
								Pakerort						482.2 *
								Pakerort						485 *
														485.4 *
														486.3
														486.5