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
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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 126778 collections

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International Chronostratigraphic Timescale			Cambrian of West Avalonia	Ordovician of China			Ordovician of the Baltic				Silurian of the Baltic
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		Hirnantian	Xiaoxita †/Shikou	Wufeng †	Harju	Porkuni				443.8
		Katian		Chientangkiangian		Wufeng †		Pirgu				445.2
				Neichianshanian/Hanjiang				Pirgu				449.5
								Vormsi				449.6 *
								Nabala	Johvi †			450 *
							Viru	Rakvere				450.6 *
								Oandu				452 *
		Sandbian						Keila	Idavere †			453
								Haljala				453.9
								Kukruse				456.4 *
								Uhaku	Aluoja †			457.5 *
	Middle Ordovician	Darriwilian		Darriwilian	Guniu †/Hulo			Uhaku				458.4
								Lasnamagi				458.9 *
								Aseri				460.4 *
							Oeland	Kunda				462.9 *
									Valaste †/Hunderum			464.3 *
					Hunjiang †	Dawan †/Daobaowan/Ningkuo						466.3 *
								Volkhov		Langevoja †/Vaana/Saka		467.1 *
		Dapingian		Dapingian				Volkhov				467.3
		Dapingian		Dapingian				Billingen				469.3 *
	Early Ordovician	Floian		Yiyangian								470
									Latorp †			470.1 *
								Hunneberg				473.7 *
		Tremadocian		Xinchangian								477.7
						Lianghekou †						477.9 *
								Varangu				481.3 *
								Pakerort				482.2 *
Cambrian	Furongian	Stage 10						Pakerort				485.4
												486.3 *
												486.5
		Jiangshanian										489.5
		Paibian										494
	Miaolingian	Guzhangian										497
		Guzhangian	Arcadian									498.4
		Drumian										500.5
		Wuliuan										504.5
	Series 2	Stage 4	Branchian									509
		Stage 3	Branchian									514
		Stage 3	Placentian									517.1
	Terreneuvian	Stage 2										521
	Terreneuvian	Fortunian										529
												538.8