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
  • J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 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
  • B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
  • A. G. Sennikov and V. K. Golubev. 2006. Vyazniki Biotic Assemblage of the Terminal Permian. Paleontological Journal 40(suppl. 4):S475-S481 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 126701 collections

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International Chronostratigraphic TimescaleCambrian of BritainOrdovician of the BalticCambrian of West AvaloniaCambrian of ChinaCambrian of Siberia
462.9
482.2
CambrianFurongianStage 10MerionethDolgellian/TrempealeauanOelandPakerortNiucheheanTaoyuanian †BatyrbaianTavgian †Ketyan †/Yurakian485.4 *
486.3 *
486.5
Festiniogian489.2 *
JiangshanianJiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Maentwrogian493.1 *
PaibianPaibian494
Ensyan †/Maduan/Nganasanian494.7 *
Waergangian †/Youshuanian494.9 *
MiaolingianGuzhangianSt DavidsGuzhangianWangcunian †Ayusokkanian497
Arcadian498.4
Mayan/Menevian499.5
DrumianDrumian500.5
WuliuanWuliuan/TaijangianAmgan/Solvan504.5
Series 2Stage 4CaerfaiBranchianDuyunian509
ToyonianLenian †510 *
Botomian512.5 *
Stage 3Nangaoian514
Atdabanian515.6 *
Placentian517.1
TerreneuvianStage 2MeishucunianTommotian521
Nemakit-Daldynian525.5
FortunianManykaian †529
Jinnigian530.7
538.8