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
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
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, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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 126701 collections

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International Chronostratigraphic Timescale			Ordovician of China			Ordovician of Ibero-Bohemia				Ordovician of the Baltic
Ordovician	Late Ordovician	Hirnantian	Hirnantian	Xiaoxita †/Shikou	Wufeng †	Kosovian				Harju	Porkuni			443.8
		Katian	Chientangkiangian		Wufeng †	Kralodvorian	Bohdalec †				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	Dapingian				Klabava †							467.3
						Arenigian								468
											Billingen			469.3 *
	Early Ordovician	Floian	Yiyangian											470
												Latorp †		470.1 *
											Hunneberg			473.7 *
		Tremadocian	Xinchangian			Tremadocian								477.7
					Lianghekou †									477.9 *
											Varangu			481.3 *
											Pakerort			482.2 *
														485.4 *
														486.3
														486.5