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
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
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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 126844 collections

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International Chronostratigraphic Timescale			Ordovician of North America					Ordovician of China			Ordovician of Britain
Ordovician	Late Ordovician	Hirnantian	Cincinnatian	Gamachian				Hirnantian	Xiaoxita †/Shikou	Wufeng †	Ashgill	Hirnantian			443.8
		Katian		Gamachian				Chientangkiangian				Rawtheyan			445.2
				Richmondian								Rawtheyan			446 *
												Cautleyan			448.9 *
												Pusgillian			449.3 *
								Neichianshanian/Hanjiang				Pusgillian			449.5
											Caradoc	Streffordian	Onnian †		449.6 *
				Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian										449.8 *
				Edenian											450.4 *
			Mohawkian	Chatfieldian											451.1 *
												Cheneyan			451.5 *
												Burrellian			452.7 *
		Sandbian													453
													Actonian †		453.2 *
				Turinian									Actonian †		453.7 *
													Marshbrookian †	Woolstonian †	454.2 *
													Longvillian †		455.2 *
												Aurelucian			456.8 *
			Whiterockian		Canadian †	Chazyan †/Marmor									457 *
													Soudleyan †/Harnagian/Costonian		457.4 *
	Middle Ordovician	Darriwilian						Darriwilian	Guniu †/Hulo		Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			458.4
									Guniu †/Hulo			Abereiddian/Early Llanvirn			461.3 *
									Hunjiang †	Dawan †/Daobaowan/Ningkuo					466.3 *
		Dapingian						Dapingian							467.3
											Arenig	Fennian			468.4 *
				Rangerian											469.1 *
	Early Ordovician	Floian	Ibexian	Blackhillsian		Jeffersonian †	Cassinian †	Yiyangian							470
				Blackhillsian								Whitlandian			471.1 *
				Tulean								Whitlandian			473.9 *
												Moridunian			474.3 *
		Tremadocian						Xinchangian			Tremadoc	Migneintian			477.7
										Lianghekou †					477.9 *
				Stairsian											480.3 *
				Stairsian								Cressagian			480.8 *
				Skullrockian/Demingian								Cressagian			482 *
				Skullrockian/Demingian											485 *
															485.4
															487.5