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

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International Chronostratigraphic TimescaleCarbo-Permian of the Russian PlatformPermian of the Russian PlatformObsolete Carboniferous Ages of ChinaSilurian of the BalticDevonian of Eastern North AmericaCambrian of BritainCarboniferous of Western EuropeDevonian of Germany
PermianLopingianChanghsingianMelekhovian251.902
Wuchiapingian254.14
TatarianVyatkian256.8 *
GuadalupianCapitanianSeverodvinian259.51
WordianUrzhumian264.28
Noginskian264.9 *
RoadianKazanianPovolzhian266.9
Sokian270.7 *
CisuralianKungurianKungurianIrenian/Ufimian273.01
Filipovian276.5 *
Pavlovoposadian276.8 *
Saraninian280.1 *
ArtinskianArtinskianSarginian283.5
Irginian285.9 *
Rusavkinian287.6 *
Burtsevian287.8 *
SakmarianSakmarianSterlitamakian290.1
Tastubian291.7 *
AsselianAsselianShikhanian293.52
Uskalykian294.8
Surenian297.5
Kuzel297.7
CarboniferousPennsylvanianGzhelianMapingian †298.9
StephanianStephanian C300.3 *
Stephanian B300.9 *
Stephanian A301.4 *
KasimovianDorogomilovian303.7
Khamovnikian304.8
Cantabrian305 *
Krevyakinian305.8 *
305.9
MoscovianMyachkovian307
WestphalianWestphalian D307.4 *
Podolskian308.9 *
Westphalian C309.8
Kashirian311.4 *
Vereian313.8
Westphalian B314.6
Melekessian314.8
Bashkirian315.2
Cheremshanian316.9 *
Westphalian A317 *
Prikamian318.6 *
NamurianYeadonian318.8 *
Severokeltmian319.9 *
Marsdenian320.2 *
Krasnopolyanian321.2 *
Kinderscoutian321.5 *
Voznesenian321.9 *
Alportian322 *
Chokierian323.1 *
MississippianSerpukhovianZapaltjubian323.2
Arnsbergian324 *
Protvian324.4 *
Steshevian326.8 *
Pendleian327.4 *
Tarusian329 *
ViseanVenevianWarnantianBrigantian †330.9
Mikhailovian331.9 *
Aleksinian333.7 *
Tulian335.8 *
LivianAsbian †336.3 *
Bobrikian339.9 *
MoliniacianHolkerian †/Arundian/Chadian340.2 *
Radaevkian343.4 *
TournaisianKosvianIvorian346.7
Kizelian350.7 *
Cherepetian351.9 *
Hastarian353.7 *
Karakubian354.4 *
Upinian356.3 *
Malevkian357.6 *
Gumerovian358 *
DevonianLate DevonianFamennianConewangan/Conneautan/CanadawayWocklum/Dasberg/Hemberg/Nehden358.9
FrasnianWest Fallsian/SonyeanAdorf372.2
Middle DevonianGivetianGeneseean/Taghanican/TioughnioganCazenovianGivetian382.7
EifelianSouthwoodianEifelian387.7
Early DevonianEmsianSawkillian/Deer ParkianHelderbergianEmsian393.3
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