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
  • 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
  • F. J. Prevosti, C. O. Romano, A. M. Forasiepi, S. Hemming, R. Bonini, A. M. Candela, E. Cerdeño, M. C. Madozzo Jaén, P. E. Ortiz, F. Pujos, L. Rasia, G. I. Schmidt, M. Taglioretti, R. D. E. MacPhee, and U. F. J. Pardiñas. 2021. New radiometric 40Ar–39Ar dates and faunistic analyses refine evolutionary dynamics of Neogene vertebrate assemblages in southern South America. Scientific Reports 2021(11):9830 view
  • J. J. Flynn and C. C. Swisher, III. 1995. Cenozoic South American Land Mammal Ages: correlation to global geochronology. Geochronology Time Scales and Global Stratigraphic Correlation, SEPM Special Publication 54:317-333 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 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

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

Show more time

Show linear time

International Chronostratigraphic TimescaleNorth American Land Mammal AgesSouth American Land Mammal AgesSilurian of North AmericaPaleogene Mammal Ages of AsiaCretaceous SubepochsPrecambrian of RussiaMammal Paleogene ZonesObsolete Names for ICS Units
PhanerozoicCenozoicQuaternaryHoloceneMeghalayanSaintaugustinean0
Santarosean0.0004
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate PleistoceneLujanian0.0117
Rancholabrean0.014
Chibanian0.129
Irvingtonian0.21
Ensenadan0.3 *
Calabrian0.774
Blancan1.4
SanandresianUquian †1.7 *
Gelasian1.8
NeogenePliocenePiacenzianVorohueanTertiary †2.58
Chapadmalalan2.9 *
Zanclean3.6
Montehermosan3.7 *
Hemphillian4.7
Huayquerian4.9 *
MioceneMessinian5.333
Tortonian7.246
Chasicoan7.9 *
Clarendonian9.4
Mayoan9.9 *
Laventan10.9 *
Serravallian11.63
Barstovian12.5
Colloncuran13.7 *
Langhian13.82
Friasian15.4 *
Burdigalian15.98
Santacrucian16.2 *
Hemingfordian16.3
Colhuehuapian17.4 *
Arikareean18.5
Aquitanian20.44
Deseadan20.9 *
PaleogeneOligoceneChattianTabenbulakianHsandagolianMP 30/MP 29/MP 28/MP 27/MP 26MP 2523.03
RupelianKekeamuanMP 24/MP 23/MP 22/MP 2127.82
Tinguirirican28.9 *
Whitneyan29.5
Orellan31.8
EocenePriabonianChadronianHouldjinian/Ergilian/UlangochuianMP 20/MP 19/MP 18/MP 17B/MP 17A33.9
Divisaderan35.9 *
Duchesnean37
BartonianSharamurunian/Irdinmanhan/ArshantanMP 1637.71
Uintan39.7
LutetianMP 15/MP 14/MP 13/MP 12/MP 1141.2
Mustersan41.9 *
Bridgerian46.2
YpresianBumbanianMP 10/MP 8 + 9/MP 747.8
Casamayoran47.9 *
Wasatchian50.5
Clarkforkian54.9
PaleoceneThanetianRiochicanGashatanMP 6MP 1 - 556
Tiffanian56.2
Itaboraian56.9 *
Peligran58.9 *
Selandian59.2
Torrejonian60.9
Danian61.6
Tiupampan62.4 *
Puercan63.8
MesozoicCretaceousLate CretaceousMaastrichtianSenonian66
Campanian72.1
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
PaleozoicPermianLopingianChanghsingian251.902
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
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 10485.4
Jiangshanian489.5
Paibian494
MiaolingianGuzhangianSeries 3 †497
Drumian500.5
WuliuanStage 5 †504.5
Series 2Stage 4509
Stage 3514
TerreneuvianStage 2521
Fortunian529
ProterozoicNeoproterozoicEdiacaranVendian538.8
Cryogenian635
Tonian720
Karatau800
MesoproterozoicStenian1000
Yurmatian1100
Ectasian1200
Burzyan1375
1400