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
J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 view
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 126710 collections

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International Chronostratigraphic Timescale			Ordovician of Australia	Ordovician of China			Ten Million Year Bins	Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Bolindian	Hirnantian	Xiaoxita †/Shikou	Wufeng †	Ordovician 5	Kosovian				443.8
		Katian	Bolindian	Chientangkiangian				Kralodvorian	Bohdalec †			445.2
			Eastonian	Chientangkiangian								449 *
				Neichianshanian/Hanjiang								449.5
								Berounian				449.7 *
			Gisbornian									452 *
		Sandbian					Ordovician 4					453
										Zahorany †/Vinice	Letna †	456.2 *
									Liben †			458 *
	Middle Ordovician	Darriwilian	Darriwilian	Darriwilian	Guniu †/Hulo		Ordovician 3					458.4
								Dobrotivian				458.5 *
								Oretanian				459.7 *
									Sarka †			461.7 *
					Hunjiang †	Dawan †/Daobaowan/Ningkuo			Sarka †			466.3 *
		Dapingian	Yapeenian	Dapingian			Ordovician 2		Klabava †			467.3
			Yapeenian					Arenigian				468
			Castlemainian									468.5 *
	Early Ordovician	Floian	Chewtonian	Yiyangian								470
			Bendigonian									471.8 *
			Lancefieldian									473.5 *
		Tremadocian		Xinchangian			Ordovician 1	Tremadocian				477.7
						Lianghekou †						477.9 *
			Warendian			Lianghekou †						482.8 *
												485.4