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
  • F. F. Steininger, W. A. Berggren, D. V. Kent, R. L. Bernor, S. Sen and J. Agusti. 1996. Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units. The Evolution of Western Eurasian Neogene Mammal Faunas (eds. R. L. Bernor, V. Fahlbusch, and H.-W. Mittmann) view
  • P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 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
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 126520 collections

Show more time

Show linear time

International Chronostratigraphic TimescaleOrdovician of Ibero-BohemiaEuropean Faunal ZonesCarboniferous of ChinaObsolete Precambrian AgesCenozoic Subepochs of Southern EuropeAmmonite Chrons of North AmericaCarboniferous SubepochsObsolete Names for ICS Units
PhanerozoicCenozoicQuaternaryPleistoceneLate PleistoceneTarantian0.0117
ChibanianIonian0.129
Calabrian0.774
GelasianMN 171.8
NeogenePliocenePiacenzianMN 16Tertiary †2.58
MN 153.2
Zanclean3.6
MN 144.2
MN 134.9
MioceneMessinian5.333
TortonianMN 127.246
MN 117.75
MN 108.7
MN 99.7
MN 7 + 811.1
Serravallian11.63
MN 612.8 *
LanghianMN 513.82
BurdigalianMN 415.98
MN 316.9
MN 220
Aquitanian20.44
MN 122.4
PaleogeneOligoceneChattian23.03
Rupelian27.82
EocenePriabonian33.9
Bartonian37.71
Lutetian41.2
Ypresian47.8
PaleoceneThanetian56
Selandian59.2
Danian61.6
MesozoicCretaceousLate 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
PaleozoicPermianLopingianChanghsingian251.902
WuchiapingianLongtanian †254.14
GuadalupianCapitanian259.51
Wordian264.28
Roadian266.9
CisuralianKungurian273.01
Artinskian283.5
Sakmarian290.1
Asselian293.52
CarboniferousPennsylvanianGzhelianLate Pennsylvanian298.9
Xiaodushanian300 *
Kasimovian303.7
Dalaun305.8 *
MoscovianMiddle Pennsylvanian307
BashkirianEarly Pennsylvanian315.2
Huashibanian318.5 *
Lousuan321.2 *
MississippianSerpukhovianDewunianLate Mississippian323.2
Shangsian330.8 *
ViseanMiddle Mississippian330.9
Jiusian335 *
TournaisianTangbagouanEarly Mississippian346.7
DevonianLate DevonianFamennian358.9
Frasnian372.2
Middle DevonianGivetian382.7
Eifelian387.7
Early DevonianEmsian393.3
Pragian407.6
Lochkovian410.8
SilurianPridoli419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychian433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianKosovian443.8
KatianKralodvorianBohdalec †445.2
Berounian449.7 *
Sandbian453
Zahorany †/ViniceLetna †456.2 *
Liben †458 *
Middle OrdovicianDarriwilian458.4
Dobrotivian458.5 *
Oretanian459.7 *
Sarka †461.7 *
DapingianKlabava †467.3
Arenigian468
Early OrdovicianFloian470
TremadocianTremadocian477.7
CambrianFurongianStage 10485.4
Jiangshanian489.5
Paibian494
MiaolingianGuzhangianSeries 3 †497
Drumian500.5
WuliuanStage 5 †504.5
Series 2Stage 4509
Stage 3514
TerreneuvianStage 2521
Fortunian529
ProterozoicNeoproterozoicEdiacaranVendian †Poundian †538.8
Wonokan †571.7 *
635