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
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
F. M. Gradstein, F. P. Agterberg, J. G. Ogg, J. Hardenbol, P. Van Veen, J. Thierry, and Z. Huang. 1995. A Triassic, Jurassic, and Cretaceous time scale. SEPM Special Publication 54 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
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, 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

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 China			Ordovician of the Baltic
Ordovician	Late Ordovician	Hirnantian	Hirnantian	Xiaoxita †/Shikou	Wufeng †	Harju	Porkuni			443.8
		Katian	Chientangkiangian		Wufeng †		Pirgu			445.2
			Neichianshanian/Hanjiang				Pirgu			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	Darriwilian	Guniu †/Hulo			Uhaku			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	Dapingian				Volkhov			467.3
		Dapingian	Dapingian				Billingen			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