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
  • A. G. Sennikov and V. K. Golubev. 2006. Vyazniki Biotic Assemblage of the Terminal Permian. Paleontological Journal 40(suppl. 4):S475-S481 view
  • D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • M. Freudenthal. 2006. Mammal Paleogene zones. personal communication 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 126691 collections

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International Chronostratigraphic TimescaleOrdovician of Ibero-BohemiaPermo-Triassic Subages of Eastern EuropeCambrian of SiberiaMammal Paleogene ZonesCambrian of West AvaloniaCenozoic SubepochsObsolete Names for ICS Units
QuaternaryPleistoceneLate PleistoceneLate Pleistocene0.0117
ChibanianMiddle Pleistocene0.129
CalabrianEarly Pleistocene0.774
Gelasian1.8
NeogenePliocenePiacenzianLate PlioceneTertiary †2.58
ZancleanEarly Pliocene3.6
MioceneMessinianLate Miocene5.333
Tortonian7.246
SerravallianMiddle Miocene11.63
Langhian13.82
BurdigalianEarly Miocene15.98
Aquitanian20.44
PaleogeneOligoceneChattianMP 30/MP 29/MP 28/MP 27/MP 26MP 25Late Oligocene23.03
RupelianMP 24/MP 23/MP 22/MP 21Early Oligocene27.82
EocenePriabonianMP 20/MP 19/MP 18/MP 17B/MP 17ALate Eocene33.9
BartonianMP 16Middle Eocene37.71
LutetianMP 15/MP 14/MP 13/MP 12/MP 1141.2
YpresianMP 10/MP 8 + 9/MP 7Early Eocene47.8
PaleoceneThanetianMP 6MP 1 - 5Late Paleocene56
SelandianMiddle Paleocene59.2
DanianEarly Paleocene61.6
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
Bajocian168.2
Aalenian170.9
Early JurassicToarcian174.7
Pliensbachian184.2
Sinemurian192.9
Hettangian199.5
TriassicLate TriassicRhaetian201.4
Norian208.5
Carnian227
Middle TriassicLadinian237
Anisian242
Early TriassicOlenekianVokhmian247.2
Induan251.2
PermianLopingianChanghsingian251.902
WuchiapingianLate Vyatkian/Early VyatkianLongtanian †254.14
GuadalupianCapitanianLate Severodvinian/Early Severodvinian259.51
WordianLate Urzhumian/Early Urzhumian264.28
RoadianLate Kazanian/Early Kazanian266.9
CisuralianKungurian273.01
Artinskian283.5
Sakmarian290.1
Asselian293.52
CarboniferousPennsylvanianGzhelian298.9
Kasimovian303.7
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
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
Mansian †483.55 *
CambrianFurongianStage 10BatyrbaianTavgian †Ketyan †/Yurakian485.4
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Paibian494
Ensyan †/Maduan/Nganasanian494.7 *
MiaolingianGuzhangianAyusokkanianSeries 3 †497
Arcadian498.4
Mayan/Menevian499.5
Drumian500.5
WuliuanAmgan/SolvanStage 5 †504.5
Series 2Stage 4Branchian509
ToyonianLenian †510 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
Placentian517.1
TerreneuvianStage 2Tommotian521
Nemakit-Daldynian525.5
FortunianManykaian †529
538.8