PBDB Interval

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
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
J. I. Raine, A. G. Beu, A. F. Boyes, H. J. Campbell, R. A. Cooper, J. S. Crampton, M. P. Crundwell, C. J. Hollis, and H. E. G. Morgans. 2015. Revised Calibration of the New Zealand Geological Timescale: NZGT2015/1. GNS Science Report 2012(39) view
F. F. Steininger, W. A. Berggren, D. V. Kent, R. L. Bernor, S. Sen and J. Agusti. 1996. Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units. The Evolution of Western Eurasian Neogene Mammal Faunas (eds. R. L. Bernor, V. Fahlbusch, and H.-W. Mittmann) 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

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 126701 collections

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International Chronostratigraphic Timescale			Ordovician of China			Ordovician of Australia	Ordovician of Britain				Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Hirnantian	Xiaoxita †/Shikou	Wufeng †	Bolindian	Ashgill	Hirnantian			Kosovian				443.8
		Katian	Chientangkiangian					Rawtheyan			Kralodvorian	Bohdalec †			445.2
								Cautleyan							448.9 *
						Eastonian		Cautleyan							449 *
								Pusgillian							449.3 *
			Neichianshanian/Hanjiang					Pusgillian							449.5
							Caradoc	Streffordian	Onnian †						449.6 *
								Streffordian			Berounian				449.7 *
								Cheneyan							451.5 *
						Gisbornian		Cheneyan							452 *
								Burrellian							452.7 *
		Sandbian													453
									Actonian †						453.2 *
									Marshbrookian †	Woolstonian †					454.2 *
									Longvillian †						455.2 *
													Zahorany †/Vinice	Letna †	456.2 *
								Aurelucian							456.8 *
									Soudleyan †/Harnagian/Costonian						457.4 *
									Soudleyan †/Harnagian/Costonian			Liben †			458 *
	Middle Ordovician	Darriwilian	Darriwilian	Guniu †/Hulo		Darriwilian	Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn							458.4
											Dobrotivian				458.5 *
											Oretanian				459.7 *
								Abereiddian/Early Llanvirn							461.3 *
												Sarka †			461.7 *
				Hunjiang †	Dawan †/Daobaowan/Ningkuo							Sarka †			466.3 *
		Dapingian	Dapingian			Yapeenian						Klabava †			467.3
											Arenigian				468
							Arenig	Fennian							468.4 *
						Castlemainian									468.5 *
	Early Ordovician	Floian	Yiyangian			Chewtonian									470
						Chewtonian		Whitlandian							471.1 *
						Bendigonian									471.8 *
						Lancefieldian									473.5 *
								Moridunian							474.3 *
		Tremadocian	Xinchangian				Tremadoc	Migneintian			Tremadocian				477.7
					Lianghekou †			Migneintian							477.9 *
								Cressagian							480.8 *
						Warendian		Cressagian							482.8 *
						Warendian									485 *
															485.4