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
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. F. Steininger, W. A. Berggren, D. V. Kent, R. L. Bernor, S. Sen and J. Agusti. 1996. Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units. The Evolution of Western Eurasian Neogene Mammal Faunas (eds. R. L. Bernor, V. Fahlbusch, and H.-W. Mittmann) 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

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 126778 collections

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International Chronostratigraphic Timescale			Ordovician of Britain				Ordovician of the Baltic
Ordovician	Late Ordovician	Hirnantian	Ashgill	Hirnantian			Harju	Porkuni			443.8
		Katian		Rawtheyan				Pirgu			445.2
				Cautleyan							448.9 *
				Pusgillian							449.3 *
			Caradoc	Streffordian	Onnian †			Vormsi			449.6 *
								Nabala	Johvi †		450 *
							Viru	Rakvere			450.6 *
				Cheneyan				Rakvere			451.5 *
				Cheneyan				Oandu			452 *
				Burrellian				Oandu			452.7 *
		Sandbian						Keila	Idavere †		453
					Actonian †			Keila			453.2 *
					Actonian †			Haljala			453.9
					Marshbrookian †	Woolstonian †					454.2 *
					Longvillian †						455.2 *
								Kukruse			456.4 *
				Aurelucian							456.8 *
					Soudleyan †/Harnagian/Costonian						457.4 *
					Soudleyan †/Harnagian/Costonian			Uhaku	Aluoja †		457.5 *
	Middle Ordovician	Darriwilian	Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn				Uhaku			458.4
								Lasnamagi			458.9 *
								Aseri			460.4 *
				Abereiddian/Early Llanvirn				Aseri			461.3 *
							Oeland	Kunda			462.9 *
								Kunda	Valaste †/Hunderum		464.3 *
								Volkhov		Langevoja †/Vaana/Saka	467.1 *
		Dapingian									467.3
			Arenig	Fennian							468.4 *
								Billingen			469.3 *
	Early Ordovician	Floian									470
									Latorp †		470.1 *
				Whitlandian							471.1 *
				Whitlandian				Hunneberg			473.7 *
				Moridunian							474.3 *
		Tremadocian	Tremadoc	Migneintian							477.7
				Cressagian							480.8 *
								Varangu			481.3 *
								Pakerort			482.2 *
								Pakerort			485 *
											485.4 *
											486.3
											486.5