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
  • 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
  • M. Freudenthal. 2006. Mammal Paleogene zones. personal communication view
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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

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International Chronostratigraphic TimescaleSilurian of EnglandSilurian of the Baltic
SilurianPridoliRed Downtonian/Temeside Shales/Downton CastleWhitcliffe/LeintwardineOhesaare419.2
Bringewood/Elton421.3
Kaugetuma421.7 *
LudlowLudfordianCoalbrookdaleWenlock (England)/TickwoodKuressaare423
Paadla423.4 *
Gorstian425.6
Buildwas426.4 *
WenlockHomerianRootsikula427.4
WychWoolhope428.4 *
Jaagarahu429.2 *
Sheinwoodian430.5
Jaani431.8 *
LlandoveryTelychian433.4
Adavere434 *
436.3 *
Aeronian438.5
Cowleigh Park439.3 *
Raikkula439.4 *
Rhuddanian440.8
Juuru441.4 *
443.8