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

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 128152 collections

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International Chronostratigraphic Timescale			Cambrian of China		Cambrian of Australia	Cambrian of Britain		Ordovician of China			Cambrian of Kazakhstan
Ordovician	Late Ordovician	Hirnantian						Hirnantian	Xiaoxita †/Shikou	Wufeng †		443.8
		Katian						Chientangkiangian		Wufeng †		445.2
		Katian						Neichianshanian/Hanjiang				449.5
		Sandbian						Neichianshanian/Hanjiang				453
	Middle Ordovician	Darriwilian						Darriwilian	Guniu †/Hulo			458.4
		Darriwilian						Darriwilian	Hunjiang †	Dawan †/Daobaowan/Ningkuo		466.3 *
		Dapingian						Dapingian				467.3
	Early Ordovician	Floian						Yiyangian				470
		Tremadocian						Xinchangian			Ungurian	477.7
		Tremadocian						Xinchangian		Lianghekou †	Ungurian	477.9 *
Cambrian	Furongian	Stage 10	Niuchehean	Taoyuanian †	Datsonian	Merioneth	Dolgellian/Trempealeauan				Batyrbaian	485.4
					Payntonian		Dolgellian/Trempealeauan					486.8 *
					Payntonian		Festiniogian					489.2 *
		Jiangshanian	Jiangshanian		Iverian							489.5
											Aksaian	490.7 *
											Sakian	492.2 *
							Maentwrogian					493.1 *
		Paibian	Paibian		Idamean							494
		Paibian	Paibian	Waergangian †/Youshuanian	Idamean							494.9 *
	Miaolingian	Guzhangian	Guzhangian	Wangcunian †	Mindyallan	St Davids					Ayusokkanian	497
					Boomerangian						Ayusokkanian	499
					Boomerangian							499.5
		Drumian	Drumian		Undillan						Zhanaarykian	500.5
		Drumian	Drumian		Floran						Tuesaian	503
		Wuliuan	Wuliuan/Taijangian		Templetonian						Tuesaian	504.5
					Templetonian							505.3
					Ordian							507.8 *
	Series 2	Stage 4	Duyunian			Caerfai						509
											Toyonian	510 *
											Toyonian	510.8 *
											Botomian	512.5 *
		Stage 3	Nangaoian								Botomian	514
		Stage 3	Nangaoian								Atdabanian	515.6 *
	Terreneuvian	Stage 2	Meishucunian								Tommotian	521
		Stage 2										525.5
		Fortunian										529
		Fortunian	Jinnigian									530.7
												538.8