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
M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 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

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 126762 collections

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International Chronostratigraphic Timescale			Ordovician of Ibero-Bohemia				Ordovician of the Baltic				Ordovician of China
Ordovician	Late Ordovician	Hirnantian	Kosovian				Harju	Porkuni			Hirnantian	Xiaoxita †/Shikou	Wufeng †	443.8
		Katian	Kralodvorian	Bohdalec †				Pirgu			Chientangkiangian		Wufeng †	445.2
								Pirgu			Neichianshanian/Hanjiang			449.5
								Vormsi						449.6 *
			Berounian					Vormsi						449.7 *
								Nabala	Johvi †					450 *
							Viru	Rakvere						450.6 *
								Oandu						452 *
		Sandbian						Keila	Idavere †					453
								Haljala						453.9
					Zahorany †/Vinice	Letna †		Haljala						456.2 *
								Kukruse						456.4 *
								Uhaku	Aluoja †					457.5 *
				Liben †										458 *
	Middle Ordovician	Darriwilian									Darriwilian	Guniu †/Hulo		458.4
			Dobrotivian											458.5 *
			Dobrotivian					Lasnamagi						458.9 *
			Oretanian					Lasnamagi						459.7 *
								Aseri						460.4 *
				Sarka †				Aseri						461.7 *
							Oeland	Kunda						462.9 *
									Valaste †/Hunderum					464.3 *
												Hunjiang †	Dawan †/Daobaowan/Ningkuo	466.3 *
								Volkhov		Langevoja †/Vaana/Saka				467.1 *
		Dapingian		Klabava †							Dapingian			467.3
			Arenigian											468
								Billingen						469.3 *
	Early Ordovician	Floian									Yiyangian			470
									Latorp †					470.1 *
								Hunneberg						473.7 *
		Tremadocian	Tremadocian								Xinchangian			477.7
													Lianghekou †	477.9 *
								Varangu						481.3 *
								Pakerort						482.2 *
														485.4 *
														486.3
														486.5