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
  • B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 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 126778 collections

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International Chronostratigraphic TimescaleCambrian of West AvaloniaOrdovician of the BalticCambrian of AustraliaCambrian of Siberia
462.9
482.2
CambrianFurongianStage 10OelandPakerortDatsonianBatyrbaianTavgian †Ketyan †/Yurakian485.4 *
486.3 *
486.5
Payntonian486.8 *
JiangshanianIverian489.5
Aksaian490.7 *
Sakian492.2 *
PaibianIdamean494
Ensyan †/Maduan/Nganasanian494.7 *
MiaolingianGuzhangianMindyallanAyusokkanian497
Arcadian498.4
Boomerangian499
Mayan/Menevian499.5
DrumianUndillan500.5
Floran503
WuliuanTempletonianAmgan/Solvan504.5
Ordian507.8 *
Series 2Stage 4Branchian509
ToyonianLenian †510 *
510.8 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
Placentian517.1
TerreneuvianStage 2Tommotian521
Nemakit-Daldynian525.5
FortunianManykaian †529
538.8