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. Freudenthal. 2006. Mammal Paleogene zones. personal communication view
Z.-X. Qiu and Z.-D. Qiu. 1995. Chronological sequence and subdivision of Chinese Neogene mammalian faunas. Palaeogeography, Palaeoclimatology, Palaeoecology 116(1-2):41-70 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 126762 collections

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International Chronostratigraphic Timescale			Ordovician of Britain				Ten Million Year Bins	Ordovician of North America					Ordovician of Australia
Ordovician	Late Ordovician	Hirnantian	Ashgill	Hirnantian			Ordovician 5	Cincinnatian	Gamachian				Bolindian	443.8
		Katian		Rawtheyan					Gamachian					445.2
				Rawtheyan					Richmondian					446 *
				Cautleyan										448.9 *
				Cautleyan									Eastonian	449 *
				Pusgillian										449.3 *
			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 *
				Cheneyan									Gisbornian	452 *
				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	458.4
		Darriwilian		Abereiddian/Early Llanvirn			Ordovician 3						Darriwilian	461.3 *
		Dapingian		Abereiddian/Early Llanvirn			Ordovician 2						Yapeenian	467.3
			Arenig	Fennian									Yapeenian	468.4 *
													Castlemainian	468.5 *
									Rangerian				Castlemainian	469.1 *
	Early Ordovician	Floian						Ibexian	Blackhillsian		Jeffersonian †	Cassinian †	Chewtonian	470
				Whitlandian									Chewtonian	471.1 *
													Bendigonian	471.8 *
													Lancefieldian	473.5 *
									Tulean					473.9 *
				Moridunian										474.3 *
		Tremadocian	Tremadoc	Migneintian			Ordovician 1							477.7
				Migneintian					Stairsian					480.3 *
				Cressagian					Stairsian					480.8 *
									Skullrockian/Demingian					482 *
													Warendian	482.8 *
													Warendian	485 *
														485.4
														487.5