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
  • M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
  • J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 view
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • M. Kretzoi. 1942. Necroteuthis n. g. (Ceph. Dibr., Necroteuthidae N. F.) aus dem Oligozän von Budapest und das system der Dibranchiata. Földtani Közlöny 72:125-238 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 126973 collections

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International Chronostratigraphic TimescaleCambrian of BritainNorth American Mammal Subages/ZonesObsolete Names for ICS UnitsCambrian of North AmericaOrdovician of North America
QuaternaryHoloceneMeghalayan0
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate PleistoceneSheridanian0.0117
Chibanian0.129
Cudahyan/Sappan0.21
Calabrian0.774
Senecan/Rexroadian1.4
Gelasian1.8
NeogenePliocenePiacenzianTertiary †2.58
Zanclean3.6
Late Hemphillian/late Early Hemphillian/early Early Hemphillian4.7
MioceneMessinian5.333
Tortonian7.246
Late Clarendonian/Early Clarendonian9.4
Serravallian11.63
late Late Barstovian/early Late Barstovian/Early Barstovian12.5
Langhian13.82
Burdigalian15.98
Late Hemingfordian/Early Hemingfordian16.3
late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonian18.5
Aquitanian20.44
PaleogeneOligoceneChattian23.03
Monroecreekian23.1 *
Geringian24.7 *
Rupelian27.82
29.5
EocenePriabonianLate Chadronian/Middle Chadronian/Early Chadronian33.9
37
Bartonian37.71
Late Uintan/Early Uintan39.7
Lutetian41.2
Twinbuttean/Blacksforkian/Gardnerbuttian46.2
Ypresian47.8
Lostcabinian/Lysitean/Graybullian/Sandcouleean50.5
Cf3/Cf2/Cf154.9
PaleoceneThanetian56
Ti6/Ti5/Ti4/Ti3/Ti2/Ti156.2
Selandian59.2
To3/To2/To160.9
Danian61.6
Pu3/Pu2/Pu163.8
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
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 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 OrdovicianHirnantianCincinnatianGamachian443.8
Katian445.2
Richmondian446 *
MaysvillianRocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian449.8 *
Edenian450.4 *
MohawkianChatfieldian451.1 *
Sandbian453
Turinian453.7 *
WhiterockianCanadian †Chazyan †/Marmor457 *
Middle OrdovicianDarriwilian458.4
Dapingian467.3
Rangerian469.1 *
Early OrdovicianFloianIbexianBlackhillsianJeffersonian †Cassinian †470
Tulean473.9 *
Tremadocian477.7
Stairsian480.3 *
SkullrockianDemingian †482 *
CambrianFurongianStage 10MerionethDolgellian/TrempealeauanFranconian †/Dresbachian/Millardan485.4
Sunwaptan487.5
Festiniogian489.2 *
Jiangshanian489.5
Steptoean493 *
Maentwrogian493.1 *
Paibian494
MiaolingianGuzhangianSt DavidsSeries 3 †MarjumianAlbertian †497
Drumian500.5
WuliuanStage 5 †Topazan504.5
Delamaran506.5
Series 2Stage 4CaerfaiWaucoban †509
Dyeran511 *
Stage 3514
Montezuman514.8 *
Begadean519.9 *
TerreneuvianStage 2521
Fortunian529
538.8