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, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • J. Palfy, P. L. Smith, and J. K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time scale for the Jurassic. Canadian Journal of Earth Sciences 37(6):923-944 view
  • F. M. Gradstein, F. P. Agterberg, J. G. Ogg, J. Hardenbol, P. Van Veen, J. Thierry, and Z. Huang. 1995. A Triassic, Jurassic, and Cretaceous time scale. SEPM Special Publication 54 view
  • J. I. Raine, A. G. Beu, A. F. Boyes, H. J. Campbell, R. A. Cooper, J. S. Crampton, M. P. Crundwell, C. J. Hollis, and H. E. G. Morgans. 2015. Revised Calibration of the New Zealand Geological Timescale: NZGT2015/1. GNS Science Report 2012(39) 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 126699 collections

Show more time

Show linear time

International Chronostratigraphic TimescaleObsolete Names for ICS UnitsCambrian of KazakhstanCambrian of West Avalonia
CambrianFurongianStage 10Batyrbaian485.4
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Paibian494
MiaolingianGuzhangianSeries 3 †Ayusokkanian497
Arcadian498.4
499.5
DrumianZhanaarykian500.5
Tuesaian503
WuliuanStage 5 †504.5
505.3
Series 2Stage 4Branchian509
Toyonian510 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
Placentian517.1
TerreneuvianStage 2Tommotian521
525.5
Fortunian529
538.8