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
  • M. Freudenthal. 2006. Mammal Paleogene zones. personal communication 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, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. view
  • A. D. Barnosky, M. Holmes, R. Kirchholtes, E. Lindsey, K.C. Maguire, A.W. Poust, M.A. Stegner, J. Sunseri, B. Swartz, J. Swift, N.A. Villavicencio and G. Wogan. 2014. Prelude to the Anthropocene: Two new North American Land Mammal Ages (NALMAs). The Anthropocene Review I(3):225-242 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 126011 collections

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International Chronostratigraphic TimescaleMammal Paleogene ZonesObsolete Names for ICS UnitsCenozoic SubepochsAmmonite Chrons of North AmericaCambrian of SiberiaCarbo-Permian of the Russian PlatformCambrian of AustraliaNorth American Land Mammal Ages
QuaternaryHoloceneMeghalayanSaintaugustinean0
Santarosean0.0004
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate PleistoceneLate Pleistocene0.0117
Rancholabrean0.014
ChibanianMiddle Pleistocene0.129
Irvingtonian0.21
CalabrianEarly Pleistocene0.774
Blancan1.4
Gelasian1.8
NeogenePliocenePiacenzianTertiary †Late Pliocene2.58
ZancleanEarly Pliocene3.6
Hemphillian4.7
MioceneMessinianLate Miocene5.333
Tortonian7.246
Clarendonian9.4
SerravallianMiddle Miocene11.63
Barstovian12.5
Langhian13.82
BurdigalianEarly Miocene15.98
Hemingfordian16.3
Arikareean18.5
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
Whitneyan29.5
Orellan31.8
EocenePriabonianMP 20/MP 19/MP 18/MP 17B/MP 17ALate EoceneChadronian33.9
Duchesnean37
BartonianMP 16Middle Eocene37.71
Uintan39.7
LutetianMP 15/MP 14/MP 13/MP 12/MP 1141.2
Bridgerian46.2
YpresianMP 10/MP 8 + 9/MP 7Early Eocene47.8
Wasatchian50.5
Clarkforkian54.9
PaleoceneThanetianMP 6MP 1 - 5Late Paleocene56
Tiffanian56.2
SelandianMiddle Paleocene59.2
Torrejonian60.9
DanianEarly Paleocene61.6
Puercan63.8
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
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
PermianLopingianChanghsingianMelekhovian251.902
WuchiapingianLongtanian †254.14
GuadalupianCapitanian259.51
Wordian264.28
Noginskian264.9 *
Roadian266.9
CisuralianKungurian273.01
Pavlovoposadian276.8 *
Artinskian283.5
Rusavkinian287.6 *
Sakmarian290.1
Asselian293.52
CarboniferousPennsylvanianGzhelian298.9
KasimovianDorogomilovian303.7
Khamovnikian304.8
Krevyakinian305.8 *
MoscovianMyachkovian307
Podolskian308.9 *
Kashirian311.4 *
Vereian313.8
Melekessian314.8
Bashkirian315.2
Cheremshanian316.9 *
Prikamian318.6 *
Severokeltmian319.9 *
Krasnopolyanian321.2 *
Voznesenian321.9 *
MississippianSerpukhovianZapaltjubian323.2
Protvian324.4 *
Steshevian326.8 *
Tarusian329 *
ViseanVenevian330.9
Mikhailovian331.9 *
Aleksinian333.7 *
Tulian335.8 *
Bobrikian339.9 *
Radaevkian343.4 *
TournaisianKosvian346.7
Kizelian350.7 *
Cherepetian351.9 *
Karakubian354.4 *
Upinian356.3 *
Malevkian357.6 *
Gumerovian358 *
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 OrdovicianHirnantian443.8
Katian445.2
Sandbian453
Middle OrdovicianDarriwilian458.4
Dapingian467.3
Early OrdovicianFloian470
Tremadocian477.7
Mansian †483.55 *
CambrianFurongianStage 10BatyrbaianTavgian †Ketyan †/YurakianDatsonian485.4
Payntonian486.8 *
JiangshanianIverian489.5
Aksaian490.7 *
Sakian492.2 *
PaibianIdamean494
Ensyan †/Maduan/Nganasanian494.7 *
MiaolingianGuzhangianSeries 3 †AyusokkanianMindyallan497
Boomerangian499
Mayan/Menevian499.5
DrumianUndillan500.5
Floran503
WuliuanStage 5 †Amgan/SolvanTempletonian504.5
Ordian507.8 *
Series 2Stage 4509
ToyonianLenian †510 *
510.8 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
TerreneuvianStage 2Tommotian521
Nemakit-Daldynian525.5
FortunianManykaian †529
538.8