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
  • 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, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 126849 collections

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International Chronostratigraphic TimescaleDevonian of GermanyCarboniferous of ChinaPermian of North AmericaObsolete Carboniferous Ages of ChinaDevonian of Eastern North AmericaCambrian of BritainCarboniferous of Western EuropeSilurian of the Baltic
PermianGuadalupianCapitanianCapitanian259.51
WordianWordian264.28
RoadianRoadian266.9
CisuralianKungurianLeonardianCathedralian273.01
Hessian281.9 *
Artinskian283.5
WolfcampianLenoxian286.1 *
Sakmarian290.1
AsselianNealian293.52
Kuzel297.7
CarboniferousPennsylvanianGzhelianMapingian †298.9
Xiaodushanian300 *
StephanianStephanian C300.3 *
Stephanian B300.9 *
Stephanian A301.4 *
Kasimovian303.7
Cantabrian305 *
Dalaun305.8 *
305.9
Moscovian307
WestphalianWestphalian D307.4 *
Westphalian C309.8
Westphalian B314.6
Bashkirian315.2
Westphalian A317 *
Huashibanian318.5 *
NamurianYeadonian318.8 *
Marsdenian320.2 *
Lousuan321.2 *
Kinderscoutian321.5 *
Alportian322 *
Chokierian323.1 *
MississippianSerpukhovianDewunian323.2
Arnsbergian324 *
Pendleian327.4 *
Shangsian330.8 *
ViseanWarnantianBrigantian †330.9
Jiusian335 *
LivianAsbian †336.3 *
MoliniacianHolkerian †/Arundian/Chadian340.2 *
TournaisianTangbagouanIvorian346.7
Hastarian353.7 *
DevonianLate DevonianFamennianWocklum/Dasberg/Hemberg/NehdenConewangan/Conneautan/Canadaway358.9
FrasnianAdorfWest Fallsian/Sonyean372.2
Middle DevonianGivetianGivetianGeneseean/Taghanican/TioughnioganCazenovian382.7
EifelianEifelianSouthwoodian387.7
Early DevonianEmsianEmsianSawkillian/Deer ParkianHelderbergian393.3
PragianSiegen407.6
LochkovianGedinnine410.8
SilurianPridoliOhesaare419.2
Kaugetuma421.7 *
LudlowLudfordianKuressaare423
Paadla423.4 *
Gorstian425.6
WenlockHomerianRootsikula427.4
Jaagarahu429.2 *
Sheinwoodian430.5
Jaani431.8 *
LlandoveryTelychian433.4
Adavere434 *
Aeronian438.5
Raikkula439.4 *
Rhuddanian440.8
Juuru441.4 *
OrdovicianLate OrdovicianHirnantian443.8
Katian445.2
Sandbian453
Middle OrdovicianDarriwilian458.4
Dapingian467.3
Early OrdovicianFloian470
Tremadocian477.7
CambrianFurongianStage 10MerionethDolgellian/Trempealeauan485.4
Festiniogian489.2 *
Jiangshanian489.5
Maentwrogian493.1 *
Paibian494
MiaolingianGuzhangianSt Davids497
Drumian500.5
Wuliuan504.5
Series 2Stage 4Caerfai509
Stage 3514
TerreneuvianStage 2521
Fortunian529
538.8