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

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 126164 collections

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International Chronostratigraphic Timescale			Ordovician of Britain				Ordovician of North America					Ten Million Year Bins	Ordovician of China
Ordovician	Late Ordovician	Hirnantian	Ashgill	Hirnantian			Cincinnatian	Gamachian				Ordovician 5	Hirnantian	Xiaoxita †/Shikou	Wufeng †	443.8
		Katian		Rawtheyan				Gamachian					Chientangkiangian			445.2
				Rawtheyan				Richmondian								446 *
				Cautleyan												448.9 *
				Pusgillian												449.3 *
				Pusgillian									Neichianshanian/Hanjiang			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										Ordovician 4				453
					Actonian †											453.2 *
					Actonian †			Turinian								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	Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn								Ordovician 3	Darriwilian	Guniu †/Hulo		458.4
				Abereiddian/Early Llanvirn										Guniu †/Hulo		461.3 *
														Hunjiang †	Dawan †/Daobaowan/Ningkuo	466.3 *
		Dapingian										Ordovician 2	Dapingian			467.3
			Arenig	Fennian												468.4 *
								Rangerian								469.1 *
	Early Ordovician	Floian					Ibexian	Blackhillsian		Jeffersonian †	Cassinian †		Yiyangian			470
				Whitlandian				Blackhillsian								471.1 *
				Whitlandian				Tulean								473.9 *
				Moridunian												474.3 *
		Tremadocian	Tremadoc	Migneintian								Ordovician 1	Xinchangian			477.7
															Lianghekou †	477.9 *
								Stairsian								480.3 *
				Cressagian				Stairsian								480.8 *
				Cressagian				Skullrockian/Demingian								482 *
								Skullrockian/Demingian								485 *
																485.4
																487.5