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
  • 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 127682 collections

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International Chronostratigraphic TimescaleCambrian of SiberiaOrdovician of ChinaCambrian of BritainPermian Subages of GermanyOrdovician of Ibero-BohemiaCambrian of North AmericaCarboniferous of North AmericaDevonian of Germany
PermianLopingianChanghsingianBuntsandstein251.902
Wuchiapingian254.14
GuadalupianCapitanianOhre/Aller259.51
WordianLeine264.28
Roadian266.9
CisuralianKungurian273.01
Artinskian283.5
Sakmarian290.1
AsselianBursumian †293.52
CarboniferousPennsylvanianGzhelianVirgilian298.9
KasimovianMissourian303.7
Desmoinesian305.9 *
Moscovian307
Atokan312.7 *
Bashkirian315.2
Morrowan318.4 *
MississippianSerpukhovianChesterian323.2
Visean330.9
Meramecian335.8 *
Osagean343.1 *
Tournaisian346.7
Kinderhookian351.9 *
DevonianLate DevonianFamennianWocklum/Dasberg/Hemberg/Nehden358.9
FrasnianAdorf372.2
Middle DevonianGivetianGivetian382.7
EifelianEifelian387.7
Early DevonianEmsianEmsian393.3
PragianSiegen407.6
LochkovianGedinnine410.8
SilurianPridoli419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychian433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianHirnantianXiaoxita †/ShikouWufeng †Kosovian443.8
KatianChientangkiangianKralodvorianBohdalec †445.2
Neichianshanian/Hanjiang449.5
Berounian449.7 *
Sandbian453
Zahorany †/ViniceLetna †456.2 *
Liben †458 *
Middle OrdovicianDarriwilianDarriwilianGuniu †/Hulo458.4
Dobrotivian458.5 *
Oretanian459.7 *
Sarka †461.7 *
Hunjiang †Dawan †/Daobaowan/Ningkuo466.3 *
DapingianDapingianKlabava †467.3
Arenigian468
Early OrdovicianFloianYiyangian470
TremadocianXinchangianTremadocian477.7
Lianghekou †477.9 *
Mansian †483.55 *
CambrianFurongianStage 10BatyrbaianTavgian †Ketyan †/YurakianMerionethDolgellian/TrempealeauanFranconian †/Dresbachian/Millardan485.4
Sunwaptan487.5
Festiniogian489.2 *
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Steptoean493 *
Maentwrogian493.1 *
Paibian494
Ensyan †/Maduan/Nganasanian494.7 *
MiaolingianGuzhangianAyusokkanianSt DavidsMarjumianAlbertian †497
Mayan/Menevian499.5
Drumian500.5
WuliuanAmgan/SolvanTopazan504.5
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