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
  • 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
  • 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

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 125914 collections

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International Chronostratigraphic TimescaleCambrian of AustraliaOrdovician of North AmericaCambrian of West Avalonia
470
482
CambrianFurongianStage 10DatsonianIbexianSkullrockian485.4 *
Payntonian486.8 *
487.5
JiangshanianIverian489.5
PaibianIdamean494
MiaolingianGuzhangianMindyallan497
Arcadian498.4
Boomerangian499
DrumianUndillan500.5
Floran503
WuliuanTempletonian504.5
Ordian507.8 *
Series 2Stage 4Branchian509
510.8 *
Stage 3514
Placentian517.1
TerreneuvianStage 2521
Fortunian529
538.8