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
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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

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International Chronostratigraphic Timescale			Ordovician of Britain				Silurian of the Baltic	Carboniferous of North America	Permian of the Salt Range
Triassic	Early Triassic	Induan							Kathwai	251.5 *
Permian	Lopingian	Changhsingian							Kathwai	251.902
										252.4 *
									Chhidru	252.9 *
		Wuchiapingian							Chhidru	254.14
									Kalabagh	255 *
									Wargal	256 *
	Guadalupian	Capitanian								259.51
		Wordian								264.28
										265.3 *
									Amb	266.1 *
		Roadian							Amb	266.9
		Roadian								270.7 *
	Cisuralian	Kungurian								273.01
		Artinskian								283.5
		Sakmarian								290.1
		Asselian						Bursumian †		293.52
Carboniferous	Pennsylvanian	Gzhelian						Virgilian		298.9
		Kasimovian						Missourian		303.7
		Kasimovian						Desmoinesian		305.9 *
		Moscovian						Desmoinesian		307
		Moscovian						Atokan		312.7 *
		Bashkirian						Atokan		315.2
		Bashkirian						Morrowan		318.4 *
	Mississippian	Serpukhovian						Chesterian		323.2
		Visean						Chesterian		330.9
								Meramecian		335.8 *
								Osagean		343.1 *
		Tournaisian						Osagean		346.7
		Tournaisian						Kinderhookian		351.9 *
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						Ohesaare			419.2
	Pridoli						Kaugetuma			421.7 *
	Ludlow	Ludfordian					Kuressaare			423
		Ludfordian					Paadla			423.4 *
		Gorstian					Paadla			425.6
	Wenlock	Homerian					Rootsikula			427.4
		Homerian					Jaagarahu			429.2 *
		Sheinwoodian					Jaagarahu			430.5
		Sheinwoodian					Jaani			431.8 *
	Llandovery	Telychian					Jaani			433.4
		Telychian					Adavere			434 *
		Aeronian					Adavere			438.5
		Aeronian					Raikkula			439.4 *
		Rhuddanian					Raikkula			440.8
		Rhuddanian					Juuru			441.4 *
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 *