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
  • 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
  • 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 127057 collections

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International Chronostratigraphic TimescaleCambrian of SiberiaDevonian of Eastern North AmericaObsolete Carboniferous Ages of ChinaOrdovician of North AmericaCambrian of KazakhstanDevonian of GermanyOrdovician of ChinaCambrian of North AmericaCambrian of ChinaDevonian of Czechoslovakia
CarboniferousPennsylvanianGzhelianMapingian †298.9
Kasimovian303.7
305.9
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennianConewangan/Conneautan/CanadawayWocklum/Dasberg/Hemberg/Nehden358.9
FrasnianWest Fallsian/SonyeanAdorf372.2
Middle DevonianGivetianGeneseean/Taghanican/TioughnioganCazenovianGivetianSrbsko382.7
EifelianSouthwoodianEifelianChotec387.7
Early DevonianEmsianSawkillian/Deer ParkianHelderbergianEmsianDaleje/Zlichovian393.3
PragianSiegenPragian407.6
LochkovianGedinnineLochkovian410.8
SilurianPridoli419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychian433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianCincinnatianGamachianHirnantianXiaoxita †/ShikouWufeng †443.8
KatianChientangkiangian445.2
Richmondian446 *
Neichianshanian/Hanjiang449.5
MaysvillianRocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian449.8 *
Edenian450.4 *
MohawkianChatfieldian451.1 *
Sandbian453
Turinian453.7 *
WhiterockianCanadian †Chazyan †/Marmor457 *
Middle OrdovicianDarriwilianDarriwilianGuniu †/Hulo458.4
Hunjiang †Dawan †/Daobaowan/Ningkuo466.3 *
DapingianDapingian467.3
Rangerian469.1 *
Early OrdovicianFloianIbexianBlackhillsianJeffersonian †Cassinian †Yiyangian470
Tulean473.9 *
TremadocianUngurianXinchangian477.7
Lianghekou †477.9 *
Stairsian480.3 *
SkullrockianDemingian †482 *
Mansian †483.55 *
CambrianFurongianStage 10BatyrbaianTavgian †Ketyan †/YurakianBatyrbaianFranconian †/Dresbachian/MillardanNiucheheanTaoyuanian †485.4
Sunwaptan487.5
JiangshanianJiangshanian489.5
AksaianAksaian490.7 *
SakianSakian492.2 *
Steptoean493 *
PaibianPaibian494
Ensyan †/Maduan/Nganasanian494.7 *
Waergangian †/Youshuanian494.9 *
MiaolingianGuzhangianAyusokkanianAyusokkanianMarjumianAlbertian †GuzhangianWangcunian †497
Mayan/Menevian499.5
DrumianZhanaarykianDrumian500.5
Tuesaian503
WuliuanAmgan/SolvanTopazanWuliuan/Taijangian504.5
505.3
Delamaran506.5
Series 2Stage 4Waucoban †Duyunian509
ToyonianLenian †Toyonian510 *
Dyeran511 *
BotomianBotomian512.5 *
Stage 3Nangaoian514
Montezuman514.8 *
AtdabanianAtdabanian515.6 *
Begadean519.9 *
TerreneuvianStage 2TommotianTommotianMeishucunian521
Nemakit-Daldynian525.5
FortunianManykaian †529
Jinnigian530.7
538.8