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, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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

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 126691 collections

Show more time

Show linear time

International Chronostratigraphic Timescale			Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Kosovian				443.8
		Katian	Kralodvorian	Bohdalec †			445.2
		Katian	Berounian				449.7 *
		Sandbian					453
					Zahorany †/Vinice	Letna †	456.2 *
				Liben †			458 *
	Middle Ordovician	Darriwilian					458.4
			Dobrotivian				458.5 *
			Oretanian				459.7 *
				Sarka †			461.7 *
		Dapingian		Klabava †			467.3
		Dapingian	Arenigian				468
	Early Ordovician	Floian	Arenigian				470
	Early Ordovician	Tremadocian	Tremadocian				477.7
							485.4