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, 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
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 view
  • D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. 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 126831 collections

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International Chronostratigraphic TimescaleCambrian EpochsObsolete Names for ICS UnitsSilurian of the BalticCretaceous SubepochsCretaceous North American Land-Mammal AgesOrdovician of AustraliaCambrian of SiberiaDevonian of Germany
NeogenePliocenePiacenzianTertiary †2.58
Zanclean3.6
MioceneMessinian5.333
Tortonian7.246
Serravallian11.63
Langhian13.82
Burdigalian15.98
Aquitanian20.44
PaleogeneOligoceneChattian23.03
Rupelian27.82
EocenePriabonian33.9
Bartonian37.71
Lutetian41.2
Ypresian47.8
PaleoceneThanetian56
Selandian59.2
Danian61.6
CretaceousLate CretaceousMaastrichtianSenonianLancian/Edmontonian66
CampanianJudithian/Aquilan72.1
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
Bajocian168.2
Aalenian170.9
Early JurassicToarcian174.7
Pliensbachian184.2
Sinemurian192.9
Hettangian199.5
TriassicLate TriassicRhaetian201.4
Norian208.5
Carnian227
Middle TriassicLadinian237
Anisian242
Early TriassicOlenekian247.2
Induan251.2
PermianLopingianChanghsingian251.902
WuchiapingianLongtanian †254.14
GuadalupianCapitanian259.51
Wordian264.28
Roadian266.9
CisuralianKungurian273.01
Artinskian283.5
Sakmarian290.1
Asselian293.52
CarboniferousPennsylvanianGzhelian298.9
Kasimovian303.7
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennianWocklum/Dasberg/Hemberg/Nehden358.9
FrasnianAdorf372.2
Middle DevonianGivetianGivetian382.7
EifelianEifelian387.7
Early DevonianEmsianEmsian393.3
PragianSiegen407.6
LochkovianGedinnine410.8
SilurianPridoliOhesaare419.2
Kaugetuma421.7 *
LudlowLudfordianKuressaare423
Paadla423.4 *
Gorstian425.6
WenlockHomerianRootsikula427.4
Jaagarahu429.2 *
Sheinwoodian430.5
Jaani431.8 *
LlandoveryTelychian433.4
Adavere434 *
Aeronian438.5
Raikkula439.4 *
Rhuddanian440.8
Juuru441.4 *
OrdovicianLate OrdovicianHirnantianBolindian443.8
Katian445.2
Eastonian449 *
Gisbornian452 *
Sandbian453
Middle OrdovicianDarriwilianDarriwilian458.4
DapingianYapeenian467.3
Castlemainian468.5 *
Early OrdovicianFloianChewtonian470
Bendigonian471.8 *
Lancefieldian473.5 *
Tremadocian477.7
Warendian482.8 *
Mansian †483.55 *
CambrianFurongianStage 10Late CambrianBatyrbaianTavgian †Ketyan †/Yurakian485.4
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Paibian494
Ensyan †/Maduan/Nganasanian494.7 *
MiaolingianGuzhangianMiddle CambrianSeries 3 †Ayusokkanian497
Mayan/Menevian499.5
Drumian500.5
WuliuanStage 5 †Amgan/Solvan504.5
Series 2Stage 4Early Cambrian509
ToyonianLenian †510 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
TerreneuvianStage 2Tommotian521
Nemakit-Daldynian525.5
FortunianManykaian †529
538.8