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
M. Kretzoi. 1942. Necroteuthis n. g. (Ceph. Dibr., Necroteuthidae N. F.) aus dem Oligozän von Budapest und das system der Dibranchiata. Földtani Közlöny 72:125-238 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. 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
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

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 126844 collections

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International Chronostratigraphic Timescale			Ordovician of North America					Ordovician of China
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian				Hirnantian	Xiaoxita †/Shikou	Wufeng †	443.8
		Katian		Gamachian				Chientangkiangian			445.2
				Richmondian				Chientangkiangian			446 *
				Richmondian				Neichianshanian/Hanjiang			449.5
				Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian						449.8 *
				Edenian							450.4 *
			Mohawkian	Chatfieldian							451.1 *
		Sandbian		Chatfieldian							453
				Turinian							453.7 *
			Whiterockian		Canadian †	Chazyan †/Marmor					457 *
	Middle Ordovician	Darriwilian						Darriwilian	Guniu †/Hulo		458.4
		Darriwilian						Darriwilian	Hunjiang †	Dawan †/Daobaowan/Ningkuo	466.3 *
		Dapingian						Dapingian			467.3
		Dapingian		Rangerian				Dapingian			469.1 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †	Yiyangian			470
		Floian		Tulean				Yiyangian			473.9 *
		Tremadocian						Xinchangian			477.7
										Lianghekou †	477.9 *
				Stairsian							480.3 *
				Skullrockian/Demingian							482 *
											485.4
											487.5