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
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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
  • B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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 126762 collections

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International Chronostratigraphic TimescaleCambrian of ChinaCambrian of North AmericaOrdovician of the Baltic
462.9
482.2
CambrianFurongianStage 10NiucheheanTaoyuanian †Franconian †/Dresbachian/MillardanOelandPakerort485.4 *
486.3 *
486.5
Sunwaptan487.5
JiangshanianJiangshanian489.5
Steptoean493 *
PaibianPaibian494
Waergangian †/Youshuanian494.9 *
MiaolingianGuzhangianGuzhangianWangcunian †MarjumianAlbertian †497
DrumianDrumian500.5
WuliuanWuliuan/TaijangianTopazan504.5
Delamaran506.5
Series 2Stage 4DuyunianWaucoban †509
Dyeran511 *
Stage 3Nangaoian514
Montezuman514.8 *
Begadean519.9 *
TerreneuvianStage 2Meishucunian521
Fortunian529
Jinnigian530.7
538.8