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
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
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
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
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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 127243 collections

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International Chronostratigraphic Timescale			Ordovician of Australia	Ordovician of Britain
Ordovician	Late Ordovician	Hirnantian	Bolindian	Ashgill	Hirnantian			443.8
		Katian			Rawtheyan			445.2
					Cautleyan			448.9 *
			Eastonian		Cautleyan			449 *
					Pusgillian			449.3 *
				Caradoc	Streffordian	Onnian †		449.6 *
					Cheneyan			451.5 *
			Gisbornian		Cheneyan			452 *
					Burrellian			452.7 *
		Sandbian						453
						Actonian †		453.2 *
						Marshbrookian †	Woolstonian †	454.2 *
						Longvillian †		455.2 *
					Aurelucian	Longvillian †		456.8 *
					Aurelucian	Soudleyan †/Harnagian/Costonian		457.4 *
	Middle Ordovician	Darriwilian	Darriwilian	Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			458.4
		Darriwilian	Darriwilian		Abereiddian/Early Llanvirn			461.3 *
		Dapingian	Yapeenian		Abereiddian/Early Llanvirn			467.3
			Yapeenian	Arenig	Fennian			468.4 *
			Castlemainian					468.5 *
	Early Ordovician	Floian	Chewtonian					470
			Chewtonian		Whitlandian			471.1 *
			Bendigonian					471.8 *
			Lancefieldian					473.5 *
					Moridunian			474.3 *
		Tremadocian		Tremadoc	Migneintian			477.7
					Cressagian			480.8 *
			Warendian		Cressagian			482.8 *
			Warendian					485 *
								485.4