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
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 Australia	Ordovician of Britain				Ordovician of the Baltic				Ordovician of China
Ordovician	Late Ordovician	Hirnantian	Bolindian	Ashgill	Hirnantian			Harju	Porkuni			Hirnantian	Xiaoxita †/Shikou	Wufeng †	443.8
		Katian			Rawtheyan				Pirgu			Chientangkiangian			445.2
					Cautleyan										448.9 *
			Eastonian		Cautleyan										449 *
					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 *
			Gisbornian		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	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	Yapeenian									Dapingian			467.3
			Yapeenian	Arenig	Fennian										468.4 *
			Castlemainian												468.5 *
			Castlemainian						Billingen						469.3 *
	Early Ordovician	Floian	Chewtonian									Yiyangian			470
										Latorp †					470.1 *
					Whitlandian										471.1 *
			Bendigonian												471.8 *
			Lancefieldian												473.5 *
									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 *
			Warendian												482.8 *
			Warendian												485 *
															485.4 *
															486.3
															486.5