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

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 126562 collections

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International Chronostratigraphic TimescaleTen Million Year BinsDevonian of CzechoslovakiaDevonian Subages
DevonianLate DevonianFamennianDevonian 5Late Famennian358.9
Middle Famennian365.3 *
Early Famennian368.5 *
FrasnianDevonian 4Late Frasnian372.2
Middle Frasnian375.4 *
Early Frasnian379.3 *
Middle DevonianGivetianDevonian 3SrbskoLate Givetian382.7
Middle Givetian383.7 *
Early Givetian385.9 *
EifelianChotecLate Eifelian387.7
Early Eifelian390.3 *
Early DevonianEmsianDevonian 2Daleje/ZlichovianLate Emsian393.3
Early Emsian398.3 *
PragianDevonian 1PragianPragian407.6
LochkovianLochkovianLate Lochkovian410.8
Middle Lochkovian412.8 *
Early Lochkovian415.6 *
419.2