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
J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 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
A. G. Sennikov and V. K. Golubev. 2006. Vyazniki Biotic Assemblage of the Terminal Permian. Paleontological Journal 40(suppl. 4):S475-S481 view
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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 126844 collections

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International Chronostratigraphic Timescale			Ordovician of the Baltic				Ordovician of China
Ordovician	Late Ordovician	Hirnantian	Harju	Porkuni			Hirnantian	Xiaoxita †/Shikou	Wufeng †	443.8
		Katian		Pirgu			Chientangkiangian		Wufeng †	445.2
				Pirgu			Neichianshanian/Hanjiang			449.5
				Vormsi						449.6 *
				Nabala	Johvi †					450 *
			Viru	Rakvere						450.6 *
				Oandu						452 *
		Sandbian		Keila	Idavere †					453
				Haljala						453.9
				Kukruse						456.4 *
				Uhaku	Aluoja †					457.5 *
	Middle Ordovician	Darriwilian		Uhaku			Darriwilian	Guniu †/Hulo		458.4
				Lasnamagi						458.9 *
				Aseri						460.4 *
			Oeland	Kunda						462.9 *
					Valaste †/Hunderum					464.3 *
								Hunjiang †	Dawan †/Daobaowan/Ningkuo	466.3 *
				Volkhov		Langevoja †/Vaana/Saka				467.1 *
		Dapingian		Volkhov			Dapingian			467.3
		Dapingian		Billingen			Dapingian			469.3 *
	Early Ordovician	Floian					Yiyangian			470
					Latorp †					470.1 *
				Hunneberg						473.7 *
		Tremadocian					Xinchangian			477.7
									Lianghekou †	477.9 *
				Varangu						481.3 *
				Pakerort						482.2 *
										485.4 *
										486.3
										486.5