PBDB Timescale

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
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

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 126778 collections

Show more time

Show linear time

International Chronostratigraphic Timescale			Ordovician of Britain				Devonian of Czechoslovakia	Devonian of Germany
Devonian	Late Devonian	Famennian						Wocklum/Dasberg/Hemberg/Nehden	358.9
	Late Devonian	Frasnian						Adorf	372.2
	Middle Devonian	Givetian					Srbsko	Givetian	382.7
	Middle Devonian	Eifelian					Chotec	Eifelian	387.7
	Early Devonian	Emsian					Daleje/Zlichovian	Emsian	393.3
		Pragian					Pragian	Siegen	407.6
		Lochkovian					Lochkovian	Gedinnine	410.8
Silurian	Pridoli								419.2
	Ludlow	Ludfordian							423
	Ludlow	Gorstian							425.6
	Wenlock	Homerian							427.4
	Wenlock	Sheinwoodian							430.5
	Llandovery	Telychian							433.4
		Aeronian							438.5
		Rhuddanian							440.8
Ordovician	Late Ordovician	Hirnantian	Ashgill	Hirnantian					443.8
		Katian		Rawtheyan					445.2
				Cautleyan					448.9 *
				Pusgillian					449.3 *
			Caradoc	Streffordian	Onnian †				449.6 *
				Cheneyan					451.5 *
				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	Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn					458.4
		Darriwilian		Abereiddian/Early Llanvirn					461.3 *
		Dapingian		Abereiddian/Early Llanvirn					467.3
		Dapingian	Arenig	Fennian					468.4 *
	Early Ordovician	Floian		Fennian					470
				Whitlandian					471.1 *
				Moridunian					474.3 *
		Tremadocian	Tremadoc	Migneintian					477.7
		Tremadocian	Tremadoc	Cressagian					480.8 *
									485 *