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. 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
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
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

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 126848 collections

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International Chronostratigraphic Timescale			Ordovician of Ibero-Bohemia				Ordovician of China			Ordovician of North America
Ordovician	Late Ordovician	Hirnantian	Kosovian				Hirnantian	Xiaoxita †/Shikou	Wufeng †	Cincinnatian	Gamachian				443.8
		Katian	Kralodvorian	Bohdalec †			Chientangkiangian				Gamachian				445.2
							Chientangkiangian				Richmondian				446 *
							Neichianshanian/Hanjiang								449.5
			Berounian												449.7 *
											Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian			449.8 *
											Edenian				450.4 *
										Mohawkian	Chatfieldian				451.1 *
		Sandbian									Chatfieldian				453
											Turinian				453.7 *
					Zahorany †/Vinice	Letna †					Turinian				456.2 *
					Zahorany †/Vinice					Whiterockian		Canadian †	Chazyan †/Marmor		457 *
				Liben †											458 *
	Middle Ordovician	Darriwilian					Darriwilian	Guniu †/Hulo							458.4
			Dobrotivian												458.5 *
			Oretanian												459.7 *
				Sarka †											461.7 *
				Sarka †				Hunjiang †	Dawan †/Daobaowan/Ningkuo						466.3 *
		Dapingian		Klabava †			Dapingian								467.3
			Arenigian												468
											Rangerian				469.1 *
	Early Ordovician	Floian					Yiyangian			Ibexian	Blackhillsian		Jeffersonian †	Cassinian †	470
		Floian					Yiyangian				Tulean				473.9 *
		Tremadocian	Tremadocian				Xinchangian								477.7
									Lianghekou †						477.9 *
											Stairsian				480.3 *
											Skullrockian/Demingian				482 *
															485.4
															487.5