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
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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 126778 collections

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International Chronostratigraphic Timescale			Ten Million Year Bins	Ordovician of the Baltic				Ordovician of Britain				Ordovician of Australia
Ordovician	Late Ordovician	Hirnantian	Ordovician 5	Harju	Porkuni			Ashgill	Hirnantian			Bolindian	443.8
		Katian			Pirgu				Rawtheyan				445.2
									Cautleyan				448.9 *
									Cautleyan			Eastonian	449 *
									Pusgillian				449.3 *
					Vormsi			Caradoc	Streffordian	Onnian †			449.6 *
					Nabala	Johvi †							450 *
				Viru	Rakvere								450.6 *
					Rakvere				Cheneyan				451.5 *
					Oandu				Cheneyan			Gisbornian	452 *
					Oandu				Burrellian				452.7 *
		Sandbian	Ordovician 4		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	Ordovician 3		Uhaku			Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			Darriwilian	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	Ordovician 2									Yapeenian	467.3
								Arenig	Fennian			Yapeenian	468.4 *
												Castlemainian	468.5 *
					Billingen							Castlemainian	469.3 *
	Early Ordovician	Floian										Chewtonian	470
						Latorp †							470.1 *
									Whitlandian				471.1 *
												Bendigonian	471.8 *
												Lancefieldian	473.5 *
					Hunneberg								473.7 *
									Moridunian				474.3 *
		Tremadocian	Ordovician 1					Tremadoc	Migneintian				477.7
									Cressagian				480.8 *
					Varangu								481.3 *
					Pakerort								482.2 *
												Warendian	482.8 *
												Warendian	485 *
													485.4 *
													486.3
													486.5