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
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 126973 collections

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International Chronostratigraphic Timescale			Ordovician of Ibero-Bohemia				Ordovician of China			Ordovician of the Baltic
Ordovician	Late Ordovician	Hirnantian	Kosovian				Hirnantian	Xiaoxita †/Shikou	Wufeng †	Harju	Porkuni			443.8
		Katian	Kralodvorian	Bohdalec †			Chientangkiangian		Wufeng †		Pirgu			445.2
							Neichianshanian/Hanjiang				Pirgu			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