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
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
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 126762 collections

Show more time

Show linear time

International Chronostratigraphic Timescale			Ammonite Chrons of North America			Devonian of Czechoslovakia	Ordovician of Ibero-Bohemia
Jurassic	Middle Jurassic	Bajocian	Epizigzagiceras								168.2
		Bajocian	Rotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense								168.4
		Aalenian	Howelli/Scissum/Westermanni								170.9
	Early Jurassic	Toarcian	Yakounensis/Hillebrandti/Crassicosta								174.7
			Planulata								179.3 *
			Planulata		Arnioceras arnouldi						179.8 *
			Kanense								181.3 *
			Carlottense								182.3 *
			Kunae								183.5 *
		Pliensbachian	Kunae								184.2
			Freboldi								185.1 *
			Whiteavesi/Imlayi	Tetraspidoceras							186.2 *
				Tetraspidoceras							189.2 *
			Plesechioceras harbledownense/Asteroceras varians/Coroniceras	Canadensis							190.3 *
		Sinemurian									192.9
			Pseudaetomoceras		Psiloceras						196.4 *
			Franziceras/Euphyllites								196.5 *
		Hettangian	Franziceras/Euphyllites								199.5
Triassic	Late Triassic	Rhaetian									201.4
		Norian									208.5
		Carnian									227
	Middle Triassic	Ladinian									237
	Middle Triassic	Anisian									242
	Early Triassic	Olenekian									247.2
	Early Triassic	Induan									251.2
Permian	Lopingian	Changhsingian									251.902
	Lopingian	Wuchiapingian									254.14
	Guadalupian	Capitanian									259.51
		Wordian									264.28
		Roadian									266.9
	Cisuralian	Kungurian									273.01
		Artinskian									283.5
		Sakmarian									290.1
		Asselian									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				Srbsko					382.7
	Middle Devonian	Eifelian				Chotec					387.7
	Early Devonian	Emsian				Daleje/Zlichovian					393.3
		Pragian				Pragian					407.6
		Lochkovian				Lochkovian					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					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