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

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.

This timescale is used in the definition of 126662 collections

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International Chronostratigraphic TimescaleTen Million Year BinsDevonian of France
DevonianLate DevonianFamennianDevonian 5Famennian358.9
FrasnianDevonian 4Frasnian372.2
Middle DevonianGivetianDevonian 3Givetian382.7
EifelianCouvinien387.7
Early DevonianEmsianDevonian 2393.3
PragianDevonian 1407.6
Coblencien408.2 *
LochkovianGedinnine410.8
419.2