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
  • 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
  • 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 126973 collections

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International Chronostratigraphic TimescaleCambrian of KazakhstanPermian of Western EuropeObsolete Carboniferous Ages of ChinaOrdovician of North AmericaDevonian of GermanyOrdovician of ChinaCambrian of North AmericaCambrian of ChinaDevonian of Czechoslovakia
PermianLopingianWuchiapingianZechstein254.14
GuadalupianCapitanianRotliegendes259.51
Wordian264.28
Roadian266.9
CisuralianKungurian273.01
ArtinskianAutunian283.5
Sakmarian290.1
Asselian293.52
CarboniferousPennsylvanianGzhelianMapingian †298.9
Kasimovian303.7
305.9
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennianWocklum/Dasberg/Hemberg/Nehden358.9
FrasnianAdorf372.2
Middle DevonianGivetianGivetianSrbsko382.7
EifelianEifelianChotec387.7
Early DevonianEmsianEmsianDaleje/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 *
CambrianFurongianStage 10BatyrbaianFranconian †/Dresbachian/MillardanNiucheheanTaoyuanian †485.4
Sunwaptan487.5
JiangshanianJiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Steptoean493 *
PaibianPaibian494
Waergangian †/Youshuanian494.9 *
MiaolingianGuzhangianAyusokkanianMarjumianAlbertian †GuzhangianWangcunian †497
499.5
DrumianZhanaarykianDrumian500.5
Tuesaian503
WuliuanTopazanWuliuan/Taijangian504.5
505.3
Delamaran506.5
Series 2Stage 4Waucoban †Duyunian509
Toyonian510 *
Dyeran511 *
Botomian512.5 *
Stage 3Nangaoian514
Montezuman514.8 *
Atdabanian515.6 *
Begadean519.9 *
TerreneuvianStage 2TommotianMeishucunian521
525.5
Fortunian529
Jinnigian530.7
538.8