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
J. I. Raine, A. G. Beu, A. F. Boyes, H. J. Campbell, R. A. Cooper, J. S. Crampton, M. P. Crundwell, C. J. Hollis, and H. E. G. Morgans. 2015. Revised Calibration of the New Zealand Geological Timescale: NZGT2015/1. GNS Science Report 2012(39) 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. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 view
P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 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 126610 collections

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International Chronostratigraphic Timescale			Cambrian of Kazakhstan	Ordovician of Britain				Ordovician of Australia	Ordovician of North America
Ordovician	Late Ordovician	Hirnantian		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												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			Darriwilian						458.4
		Darriwilian			Abereiddian/Early Llanvirn			Darriwilian						461.3 *
		Dapingian			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	Ungurian	Tremadoc	Migneintian									477.7
					Migneintian					Stairsian				480.3 *
					Cressagian					Stairsian				480.8 *
										Skullrockian/Demingian				482 *
								Warendian						482.8 *
								Warendian						485 *
														485.4
														487.5