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
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
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 126973 collections

Show more time

Show linear time

International Chronostratigraphic Timescale			Silurian of North America			Silurian of England
Silurian	Pridoli		Cayugan			Red Downtonian/Temeside Shales/Downton Castle	Whitcliffe/Leintwardine	419.2
			Cayugan				Bringewood/Elton	421.3
			Niagaran				Bringewood/Elton	422.5 *
	Ludlow	Ludfordian				Coalbrookdale	Wenlock (England)/Tickwood	423
		Gorstian						425.6
		Gorstian					Buildwas	426.4 *
	Wenlock	Homerian		Lockportian			Buildwas	427.4
		Homerian		Lockportian		Wych	Woolhope	428.4 *
		Sheinwoodian						430.5
	Llandovery	Telychian		Ontarian				433.4
		Telychian						436.3 *
		Aeronian						438.5
					Alexandrian			438.7 *
						Cowleigh Park		439.3 *
			Medinan	Clinton				440.1 *
								440.7 *
		Rhuddanian						440.8
								443.8