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
  • J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 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

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 126848 collections

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International Chronostratigraphic TimescaleCambrian of KazakhstanCambrian of North AmericaTen Million Year BinsCambrian of Britain
CambrianFurongianStage 10BatyrbaianFranconian †/Dresbachian/MillardanCambrian 5MerionethDolgellian/Trempealeauan485.4
Sunwaptan487.5
Festiniogian489.2 *
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Steptoean493 *
Maentwrogian493.1 *
Paibian494
MiaolingianGuzhangianAyusokkanianMarjumianAlbertian †Cambrian 4St Davids497
499.5
DrumianZhanaarykian500.5
Tuesaian503
WuliuanTopazanCambrian 3504.5
505.3
Delamaran506.5
Series 2Stage 4Waucoban †Caerfai509
Toyonian510 *
Dyeran511 *
Botomian512.5 *
Stage 3Cambrian 2514
Montezuman514.8 *
Atdabanian515.6 *
Begadean519.9 *
TerreneuvianStage 2Tommotian521
525.5
FortunianCambrian 1529
538.8