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
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. 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

Show more time

Show linear time

International Chronostratigraphic TimescaleObsolete Names for ICS UnitsCambrian of KazakhstanCambrian of Siberia
CambrianFurongianStage 10BatyrbaianBatyrbaianTavgian †Ketyan †/Yurakian485.4
Jiangshanian489.5
AksaianAksaian490.7 *
SakianSakian492.2 *
Paibian494
Ensyan †/Maduan/Nganasanian494.7 *
MiaolingianGuzhangianSeries 3 †AyusokkanianAyusokkanian497
Mayan/Menevian499.5
DrumianZhanaarykian500.5
Tuesaian503
WuliuanStage 5 †Amgan/Solvan504.5
505.3
Series 2Stage 4509
ToyonianToyonianLenian †510 *
BotomianBotomian512.5 *
Stage 3514
AtdabanianAtdabanian515.6 *
TerreneuvianStage 2TommotianTommotian521
Nemakit-Daldynian525.5
FortunianManykaian †529
538.8