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
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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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 126848 collections

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International Chronostratigraphic Timescale			Ten Million Year Bins	Ordovician of North America					Ordovician of Australia
Ordovician	Late Ordovician	Hirnantian	Ordovician 5	Cincinnatian	Gamachian				Bolindian	443.8
		Katian			Gamachian					445.2
					Richmondian					446 *
					Richmondian				Eastonian	449 *
					Maysvillian	Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian				449.8 *
					Edenian					450.4 *
				Mohawkian	Chatfieldian					451.1 *
									Gisbornian	452 *
		Sandbian	Ordovician 4							453
					Turinian					453.7 *
				Whiterockian		Canadian †	Chazyan †/Marmor			457 *
	Middle Ordovician	Darriwilian	Ordovician 3						Darriwilian	458.4
		Dapingian	Ordovician 2						Yapeenian	467.3
									Castlemainian	468.5 *
					Rangerian				Castlemainian	469.1 *
	Early Ordovician	Floian		Ibexian	Blackhillsian		Jeffersonian †	Cassinian †	Chewtonian	470
									Bendigonian	471.8 *
									Lancefieldian	473.5 *
					Tulean					473.9 *
		Tremadocian	Ordovician 1		Tulean					477.7
					Stairsian					480.3 *
					Skullrockian/Demingian					482 *
					Skullrockian/Demingian				Warendian	482.8 *
										485.4
										487.5