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
  • M. Freudenthal. 2006. Mammal Paleogene zones. personal communication view
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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 126848 collections

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International Chronostratigraphic TimescaleDevonian of Eastern North AmericaObsolete Carboniferous Ages of ChinaCambrian EpochsMammal Paleogene ZonesSilurian of North AmericaPermian of China
PaleogeneOligoceneChattianMP 30/MP 29/MP 28/MP 27/MP 26MP 2523.03
RupelianMP 24/MP 23/MP 22/MP 2127.82
EocenePriabonianMP 20/MP 19/MP 18/MP 17B/MP 17A33.9
BartonianMP 1637.71
LutetianMP 15/MP 14/MP 13/MP 12/MP 1141.2
YpresianMP 10/MP 8 + 9/MP 747.8
PaleoceneThanetianMP 6MP 1 - 556
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
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
PermianLopingianChanghsingianMeishanian251.902
Baoqingian253.4 *
WuchiapingianLaoshanian254.14
Laibinian257.7 *
GuadalupianCapitanianLengwuan259.51
WordianKuhfengian264.28
Roadian266.9
CisuralianKungurianLuodianian273.01
Artinskian283.5
Longlinian285.4 *
Sakmarian290.1
AsselianZisongian293.52
CarboniferousPennsylvanianGzhelianMapingian †298.9
300.1
Kasimovian303.7
305.9
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennianConewangan/Conneautan/Canadaway358.9
FrasnianWest Fallsian/Sonyean372.2
Middle DevonianGivetianGeneseean/Taghanican/TioughnioganCazenovian382.7
EifelianSouthwoodian387.7
Early DevonianEmsianSawkillian/Deer ParkianHelderbergian393.3
Pragian407.6
Lochkovian410.8
SilurianPridoliCayugan419.2
Niagaran422.5 *
LudlowLudfordian423
Gorstian425.6
WenlockHomerianLockportian427.4
Sheinwoodian430.5
LlandoveryTelychianOntarian433.4
Aeronian438.5
Alexandrian438.7 *
MedinanClinton440.1 *
440.7 *
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantian443.8
Katian445.2
Sandbian453
Middle OrdovicianDarriwilian458.4
Dapingian467.3
Early OrdovicianFloian470
Tremadocian477.7
CambrianFurongianStage 10Late Cambrian485.4
Jiangshanian489.5
Paibian494
MiaolingianGuzhangianMiddle Cambrian497
Drumian500.5
Wuliuan504.5
Series 2Stage 4Early Cambrian509
Stage 3514
TerreneuvianStage 2521
Fortunian529
538.8