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
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
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. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
M. Harzhauser and W. E. Piller. 2004. Integrated stratigraphy of the Sarmatian (Upper Middle Miocene) in the western Central Paratethys. Stratigraphy 1(1):65-86 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 126831 collections

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International Chronostratigraphic Timescale			Ordovician of Ibero-Bohemia				Ordovician of China			Ordovician of Australia
Ordovician	Late Ordovician	Hirnantian	Kosovian				Hirnantian	Xiaoxita †/Shikou	Wufeng †	Bolindian	443.8
		Katian	Kralodvorian	Bohdalec †			Chientangkiangian			Bolindian	445.2
							Chientangkiangian			Eastonian	449 *
							Neichianshanian/Hanjiang				449.5
			Berounian								449.7 *
										Gisbornian	452 *
		Sandbian									453
					Zahorany †/Vinice	Letna †					456.2 *
				Liben †							458 *
	Middle Ordovician	Darriwilian					Darriwilian	Guniu †/Hulo		Darriwilian	458.4
			Dobrotivian								458.5 *
			Oretanian								459.7 *
				Sarka †							461.7 *
				Sarka †				Hunjiang †	Dawan †/Daobaowan/Ningkuo		466.3 *
		Dapingian		Klabava †			Dapingian			Yapeenian	467.3
			Arenigian							Yapeenian	468
										Castlemainian	468.5 *
	Early Ordovician	Floian					Yiyangian			Chewtonian	470
										Bendigonian	471.8 *
										Lancefieldian	473.5 *
		Tremadocian	Tremadocian				Xinchangian				477.7
									Lianghekou †		477.9 *
									Lianghekou †	Warendian	482.8 *
											485.4