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
Z.-X. Qiu and Z.-D. Qiu. 1995. Chronological sequence and subdivision of Chinese Neogene mammalian faunas. Palaeogeography, Palaeoclimatology, Palaeoecology 116(1-2):41-70 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 126689 collections

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International Chronostratigraphic Timescale			Ordovician of the Baltic				Ordovician of Britain				Ordovician of China			Ten Million Year Bins	Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Harju	Porkuni			Ashgill	Hirnantian			Hirnantian	Xiaoxita †/Shikou	Wufeng †	Ordovician 5	Kosovian				443.8
		Katian		Pirgu				Rawtheyan			Chientangkiangian				Kralodvorian	Bohdalec †			445.2
								Cautleyan											448.9 *
								Pusgillian											449.3 *
								Pusgillian			Neichianshanian/Hanjiang								449.5
				Vormsi			Caradoc	Streffordian	Onnian †										449.6 *
				Vormsi											Berounian				449.7 *
				Nabala	Johvi †														450 *
			Viru	Rakvere															450.6 *
				Rakvere				Cheneyan											451.5 *
				Oandu				Cheneyan											452 *
				Oandu				Burrellian											452.7 *
		Sandbian		Keila	Idavere †									Ordovician 4					453
				Keila					Actonian †										453.2 *
				Haljala					Actonian †										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			Darriwilian	Guniu †/Hulo		Ordovician 3					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 *
					Valaste †/Hunderum														464.3 *
												Hunjiang †	Dawan †/Daobaowan/Ningkuo						466.3 *
				Volkhov		Langevoja †/Vaana/Saka													467.1 *
		Dapingian									Dapingian			Ordovician 2		Klabava †			467.3
															Arenigian				468
							Arenig	Fennian											468.4 *
				Billingen															469.3 *
	Early Ordovician	Floian									Yiyangian								470
					Latorp †														470.1 *
								Whitlandian											471.1 *
				Hunneberg				Whitlandian											473.7 *
								Moridunian											474.3 *
		Tremadocian					Tremadoc	Migneintian			Xinchangian			Ordovician 1	Tremadocian				477.7
								Migneintian					Lianghekou †						477.9 *
								Cressagian											480.8 *
				Varangu															481.3 *
				Pakerort															482.2 *
				Pakerort															485 *
																			485.4 *
																			486.3
																			486.5