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

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 127258 collections

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International Chronostratigraphic TimescaleCambrian of North AmericaCambrian of KazakhstanCambrian of Britain
CambrianFurongianStage 10Franconian †/Dresbachian/MillardanBatyrbaianMerionethDolgellian/Trempealeauan485.4
Sunwaptan487.5
Festiniogian489.2 *
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Steptoean493 *
Maentwrogian493.1 *
Paibian494
MiaolingianGuzhangianMarjumianAlbertian †AyusokkanianSt Davids497
499.5
DrumianZhanaarykian500.5
Tuesaian503
WuliuanTopazan504.5
505.3
Delamaran506.5
Series 2Stage 4Waucoban †Caerfai509
Toyonian510 *
Dyeran511 *
Botomian512.5 *
Stage 3514
Montezuman514.8 *
Atdabanian515.6 *
Begadean519.9 *
TerreneuvianStage 2Tommotian521
525.5
Fortunian529
538.8