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
  • D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • M. Kretzoi. 1942. Necroteuthis n. g. (Ceph. Dibr., Necroteuthidae N. F.) aus dem Oligozän von Budapest und das system der Dibranchiata. Földtani Közlöny 72:125-238 view
  • M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
  • J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 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

Show more time

Show linear time

International Chronostratigraphic TimescaleCambrian of SiberiaObsolete Names for ICS UnitsOrdovician of North AmericaCambrian of BritainCambrian of North America
470
482
CambrianFurongianStage 10BatyrbaianTavgian †Ketyan †/YurakianIbexianSkullrockianMerionethDolgellian/TrempealeauanFranconian †/Dresbachian/Millardan485.4 *
Sunwaptan487.5
Festiniogian489.2 *
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Steptoean493 *
Maentwrogian493.1 *
Paibian494
Ensyan †/Maduan/Nganasanian494.7 *
MiaolingianGuzhangianAyusokkanianSeries 3 †St DavidsMarjumianAlbertian †497
Mayan/Menevian499.5
Drumian500.5
WuliuanAmgan/SolvanStage 5 †Topazan504.5
Delamaran506.5
Series 2Stage 4CaerfaiWaucoban †509
ToyonianLenian †510 *
Dyeran511 *
Botomian512.5 *
Stage 3514
Montezuman514.8 *
Atdabanian515.6 *
Begadean519.9 *
TerreneuvianStage 2Tommotian521
Nemakit-Daldynian525.5
FortunianManykaian †529
538.8