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
  • D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. view
  • J. Palfy, P. L. Smith, and J. K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time scale for the Jurassic. Canadian Journal of Earth Sciences 37(6):923-944 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 128057 collections

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International Chronostratigraphic TimescalePermian of the PamirsCarboniferous SubepochsCambrian of SiberiaSilurian of EnglandCretaceous SubepochsCambrian of North AmericaAmmonite Chrons of Northwest EuropeCambrian of West AvaloniaCarboniferous of North America
CretaceousLate CretaceousMaastrichtianSenonian66
Campanian72.1
Santonian83.6
Coniacian86.3
Turonian89.8
Cenomanian93.9
Early CretaceousAlbianGallic100.5
Aptian113
Barremian121.4
HauterivianNeocomian125.77
Valanginian132.6
Berriasian139.8
JurassicLate JurassicTithonian145
Kimmeridgian149.2
Oxfordian154.8
Middle JurassicCallovian161.5
Bathonian165.3
BajocianParkinsoni/Garantiana/Subfurcatum/Sauzei/Laeviuscula/Discites168.2
Humphresianum168.4
AalenianConcavum/Murchisonae/Opalinum170.9
Early JurassicToarcianLevesquei/Variabilis/BifronsThouarsense174.7
180.1
Serpentinum/Falciferum/Tenuicostatum182
PliensbachianSpinatum/Margaritatus/Davoei/Ibex/Jamesoni184.2
SinemurianRaricostatum/Oxynotum/Obtusum/Turneri/Semicostatum/Bucklandi192.9
HettangianAngulata/Liasicus/Planorbis199.5
TriassicLate TriassicRhaetian201.4
Norian208.5
Carnian227
Middle TriassicLadinian237
Anisian242
Early TriassicOlenekian247.2
Induan251.2
PermianLopingianChanghsingianDorashamian251.902
WuchiapingianDzhulfian254.14
GuadalupianCapitanianMidian259.51
Wordian264.28
Murgabian266.2 *
Roadian266.9
CisuralianKungurianKubergandian273.01
Bolorian279.8
Artinskian283.5
Yakhtashian286
SakmarianSakmarian290.1
AsselianAsselianBursumian †293.52
CarboniferousPennsylvanianGzhelianLate PennsylvanianVirgilian298.9
KasimovianMissourian303.7
Desmoinesian305.9 *
MoscovianMiddle Pennsylvanian307
Atokan312.7 *
BashkirianEarly Pennsylvanian315.2
Morrowan318.4 *
MississippianSerpukhovianLate MississippianChesterian323.2
ViseanMiddle Mississippian330.9
Meramecian335.8 *
Osagean343.1 *
TournaisianEarly Mississippian346.7
Kinderhookian351.9 *
DevonianLate DevonianFamennian358.9
Frasnian372.2
Middle DevonianGivetian382.7
Eifelian387.7
Early DevonianEmsian393.3
Pragian407.6
Lochkovian410.8
SilurianPridoliRed Downtonian/Temeside Shales/Downton CastleWhitcliffe/Leintwardine419.2
Bringewood/Elton421.3
LudlowLudfordianCoalbrookdaleWenlock (England)/Tickwood423
Gorstian425.6
Buildwas426.4 *
WenlockHomerian427.4
WychWoolhope428.4 *
Sheinwoodian430.5
LlandoveryTelychian433.4
436.3 *
Aeronian438.5
Cowleigh Park439.3 *
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantian443.8
Katian445.2
Sandbian453
Middle OrdovicianDarriwilian458.4
Dapingian467.3
Early OrdovicianFloian470
Tremadocian477.7
Mansian †483.55 *
CambrianFurongianStage 10BatyrbaianTavgian †Ketyan †/YurakianFranconian †/Dresbachian/Millardan485.4
Sunwaptan487.5
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Steptoean493 *
Paibian494
Ensyan †/Maduan/Nganasanian494.7 *
MiaolingianGuzhangianAyusokkanianMarjumianAlbertian †497
Arcadian498.4
Mayan/Menevian499.5
Drumian500.5
WuliuanAmgan/SolvanTopazan504.5
Delamaran506.5
Series 2Stage 4Waucoban †Branchian509
ToyonianLenian †510 *
Dyeran511 *
Botomian512.5 *
Stage 3514
Montezuman514.8 *
Atdabanian515.6 *
Placentian517.1
Begadean519.9 *
TerreneuvianStage 2Tommotian521
Nemakit-Daldynian525.5
FortunianManykaian †529
538.8