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
  • M. Freudenthal. 2006. Mammal Paleogene zones. personal communication view
  • J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 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 126701 collections

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International Chronostratigraphic TimescaleDevonian of CzechoslovakiaPermian of the PamirsCambrian of West AvaloniaMammal Paleogene ZonesPaleogene Mammal Ages of AsiaAmmonite Chrons of North AmericaPermian of ChinaObsolete Names for ICS Units
NeogenePliocenePiacenzianTertiary †2.58
Zanclean3.6
MioceneMessinian5.333
Tortonian7.246
Serravallian11.63
Langhian13.82
Burdigalian15.98
Aquitanian20.44
PaleogeneOligoceneChattianMP 30/MP 29/MP 28/MP 27/MP 26MP 25TabenbulakianHsandagolian23.03
RupelianMP 24/MP 23/MP 22/MP 21Kekeamuan27.82
EocenePriabonianMP 20/MP 19/MP 18/MP 17B/MP 17AHouldjinian/Ergilian/Ulangochuian33.9
BartonianMP 16Sharamurunian/Irdinmanhan/Arshantan37.71
LutetianMP 15/MP 14/MP 13/MP 12/MP 1141.2
YpresianMP 10/MP 8 + 9/MP 7Bumbanian47.8
PaleoceneThanetianMP 6MP 1 - 5Gashatan56
Selandian59.2
Danian61.6
CretaceousLate CretaceousMaastrichtian66
Campanian72.1
Santonian83.6
Coniacian86.3
Turonian89.8
Cenomanian93.9
Early CretaceousAlbian100.5
Aptian113
Barremian121.4
Hauterivian125.77
Valanginian132.6
Berriasian139.8
JurassicLate JurassicTithonian145
Kimmeridgian149.2
Oxfordian154.8
Middle JurassicCallovian161.5
Bathonian165.3
BajocianEpizigzagiceras168.2
Rotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense168.4
AalenianHowelli/Scissum/Westermanni170.9
Early JurassicToarcianYakounensis/Hillebrandti/Crassicosta174.7
Planulata179.3 *
Arnioceras arnouldi179.8 *
Kanense181.3 *
Carlottense182.3 *
Kunae183.5 *
Pliensbachian184.2
Freboldi185.1 *
Whiteavesi/ImlayiTetraspidoceras186.2 *
189.2 *
Plesechioceras harbledownense/Asteroceras varians/CoronicerasCanadensis190.3 *
Sinemurian192.9
PseudaetomocerasPsiloceras196.4 *
Franziceras/Euphyllites196.5 *
Hettangian199.5
TriassicLate TriassicRhaetian201.4
Norian208.5
Carnian227
Middle TriassicLadinian237
Anisian242
Early TriassicOlenekian247.2
Induan251.2
PermianLopingianChanghsingianDorashamianMeishanian251.902
Baoqingian253.4 *
WuchiapingianDzhulfianLaoshanianLongtanian †254.14
Laibinian257.7 *
GuadalupianCapitanianMidianLengwuan259.51
WordianKuhfengian264.28
Murgabian266.2 *
Roadian266.9
CisuralianKungurianKubergandianLuodianian273.01
Bolorian279.8
Artinskian283.5
Longlinian285.4 *
Yakhtashian286
SakmarianSakmarian290.1
AsselianAsselianZisongian293.52
CarboniferousPennsylvanianGzhelian298.9
300.1
Kasimovian303.7
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennian358.9
Frasnian372.2
Middle DevonianGivetianSrbsko382.7
EifelianChotec387.7
Early DevonianEmsianDaleje/Zlichovian393.3
PragianPragian407.6
LochkovianLochkovian410.8
SilurianPridoli419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychian433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantian443.8
Katian445.2
Sandbian453
Middle OrdovicianDarriwilian458.4
Dapingian467.3
Early OrdovicianFloian470
Tremadocian477.7
CambrianFurongianStage 10485.4
Jiangshanian489.5
Paibian494
MiaolingianGuzhangianSeries 3 †497
Arcadian498.4
Drumian500.5
WuliuanStage 5 †504.5
Series 2Stage 4Branchian509
Stage 3514
Placentian517.1
TerreneuvianStage 2521
Fortunian529
538.8