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
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, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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

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International Chronostratigraphic Timescale			Silurian Ages of Europe	Permian of North America		Silurian of England		Ordovician of Ibero-Bohemia
Permian	Guadalupian	Capitanian		Capitanian								259.51
		Wordian		Wordian								264.28
		Roadian		Roadian								266.9
	Cisuralian	Kungurian		Leonardian	Cathedralian							273.01
		Kungurian			Hessian							281.9 *
		Artinskian			Hessian							283.5
		Artinskian		Wolfcampian	Lenoxian							286.1 *
		Sakmarian			Lenoxian							290.1
		Asselian			Nealian							293.52
Carboniferous	Pennsylvanian	Gzhelian										298.9
		Kasimovian										303.7
		Moscovian										307
		Bashkirian										315.2
	Mississippian	Serpukhovian										323.2
		Visean										330.9
		Tournaisian										346.7
Devonian	Late Devonian	Famennian										358.9
	Late Devonian	Frasnian										372.2
	Middle Devonian	Givetian										382.7
	Middle Devonian	Eifelian										387.7
	Early Devonian	Emsian										393.3
		Pragian										407.6
		Lochkovian										410.8
Silurian	Pridoli					Red Downtonian/Temeside Shales/Downton Castle	Whitcliffe/Leintwardine					419.2
	Pridoli					Red Downtonian/Temeside Shales/Downton Castle	Bringewood/Elton					421.3
	Ludlow	Ludfordian				Coalbrookdale	Wenlock (England)/Tickwood					423
		Gorstian										425.6
		Gorstian					Buildwas					426.4 *
	Wenlock	Homerian	Gleedonian				Buildwas					427.4
			Gleedonian			Wych	Woolhope					428.4 *
			Whitwellian									429.7 *
		Sheinwoodian										430.5
	Llandovery	Telychian										433.4
		Telychian										436.3 *
		Aeronian										438.5
		Aeronian				Cowleigh Park						439.3 *
		Rhuddanian				Cowleigh Park						440.8
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