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 126764 collections

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International Chronostratigraphic Timescale			Ordovician of Britain				Silurian of the Baltic	Cambrian of Kazakhstan	Carboniferous of North America
Permian	Cisuralian	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				Ungurian		477.7
			Tremadoc	Cressagian						480.8 *
										485 *
Cambrian	Furongian	Stage 10						Batyrbaian		485.4
		Jiangshanian						Batyrbaian		489.5
								Aksaian		490.7 *
								Sakian		492.2 *
		Paibian						Sakian		494
	Miaolingian	Guzhangian						Ayusokkanian		497
		Guzhangian								499.5
		Drumian						Zhanaarykian		500.5
		Drumian						Tuesaian		503
		Wuliuan						Tuesaian		504.5
		Wuliuan								505.3
	Series 2	Stage 4								509
								Toyonian		510 *
								Botomian		512.5 *
		Stage 3						Botomian		514
		Stage 3						Atdabanian		515.6 *
	Terreneuvian	Stage 2						Tommotian		521
										525.5