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, 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
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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
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
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 126164 collections

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