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
  • 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
  • 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
  • B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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
  • 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. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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

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 126849 collections

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International Chronostratigraphic TimescaleAmmonite Chrons of North AmericaCarboniferous of ChinaOrdovician of BritainNorth American Mammal Subages/ZonesNorth American Land Mammal AgesPermian of North AmericaDevonian of Eastern North AmericaSouth American Land Mammal AgesSilurian of the BalticDevonian of Germany
QuaternaryHoloceneMeghalayanSaintaugustinean0
Santarosean0.0004
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate PleistoceneSheridanianLujanian0.0117
Rancholabrean0.014
Chibanian0.129
Cudahyan/SappanIrvingtonian0.21
Ensenadan0.3 *
Calabrian0.774
Senecan/RexroadianBlancan1.4
SanandresianUquian †1.7 *
Gelasian1.8
NeogenePliocenePiacenzianVorohuean2.58
Chapadmalalan2.9 *
Zanclean3.6
Montehermosan3.7 *
Late Hemphillian/late Early Hemphillian/early Early HemphillianHemphillian4.7
Huayquerian4.9 *
MioceneMessinian5.333
Tortonian7.246
Chasicoan7.9 *
Late Clarendonian/Early ClarendonianClarendonian9.4
Mayoan9.9 *
Laventan10.9 *
Serravallian11.63
late Late Barstovian/early Late Barstovian/Early BarstovianBarstovian12.5
Colloncuran13.7 *
Langhian13.82
Friasian15.4 *
Burdigalian15.98
Santacrucian16.2 *
Late Hemingfordian/Early HemingfordianHemingfordian16.3
Colhuehuapian17.4 *
late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonianArikareean18.5
Aquitanian20.44
Deseadan20.9 *
PaleogeneOligoceneChattian23.03
Monroecreekian23.1 *
Geringian24.7 *
Rupelian27.82
Tinguirirican28.9 *
Whitneyan29.5
Orellan31.8
EocenePriabonianLate Chadronian/Middle Chadronian/Early ChadronianChadronian33.9
Divisaderan35.9 *
Duchesnean37
Bartonian37.71
Late Uintan/Early UintanUintan39.7
Lutetian41.2
Mustersan41.9 *
Twinbuttean/Blacksforkian/GardnerbuttianBridgerian46.2
Ypresian47.8
Casamayoran47.9 *
Lostcabinian/Lysitean/Graybullian/SandcouleeanWasatchian50.5
Cf3/Cf2/Cf1Clarkforkian54.9
PaleoceneThanetianRiochican56
Ti6/Ti5/Ti4/Ti3/Ti2/Ti1Tiffanian56.2
Itaboraian56.9 *
Peligran58.9 *
Selandian59.2
To3/To2/To1Torrejonian60.9
Danian61.6
Tiupampan62.4 *
Pu3/Pu2/Pu1Puercan63.8
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
PermianLopingianChanghsingian251.902
Wuchiapingian254.14
GuadalupianCapitanianCapitanian259.51
WordianWordian264.28
RoadianRoadian266.9
CisuralianKungurianLeonardianCathedralian273.01
Hessian281.9 *
Artinskian283.5
WolfcampianLenoxian286.1 *
Sakmarian290.1
AsselianNealian293.52
CarboniferousPennsylvanianGzhelian298.9
Xiaodushanian300 *
Kasimovian303.7
Dalaun305.8 *
Moscovian307
Bashkirian315.2
Huashibanian318.5 *
Lousuan321.2 *
MississippianSerpukhovianDewunian323.2
Shangsian330.8 *
Visean330.9
Jiusian335 *
TournaisianTangbagouan346.7
DevonianLate DevonianFamennianConewangan/Conneautan/CanadawayWocklum/Dasberg/Hemberg/Nehden358.9
FrasnianWest Fallsian/SonyeanAdorf372.2
Middle DevonianGivetianGeneseean/Taghanican/TioughnioganCazenovianGivetian382.7
EifelianSouthwoodianEifelian387.7
Early DevonianEmsianSawkillian/Deer ParkianHelderbergianEmsian393.3
PragianSiegen407.6
LochkovianGedinnine410.8
SilurianPridoliOhesaare419.2
Kaugetuma421.7 *
LudlowLudfordianKuressaare423
Paadla423.4 *
Gorstian425.6
WenlockHomerianRootsikula427.4
Jaagarahu429.2 *
Sheinwoodian430.5
Jaani431.8 *
LlandoveryTelychian433.4
Adavere434 *
Aeronian438.5
Raikkula439.4 *
Rhuddanian440.8
Juuru441.4 *
OrdovicianLate OrdovicianHirnantianAshgillHirnantian443.8
KatianRawtheyan445.2
Cautleyan448.9 *
Pusgillian449.3 *
CaradocStreffordianOnnian †449.6 *
Cheneyan451.5 *
Burrellian452.7 *
Sandbian453
Actonian †453.2 *
Marshbrookian †Woolstonian †454.2 *
Longvillian †455.2 *
Aurelucian456.8 *
Soudleyan †/Harnagian/Costonian457.4 *
Middle OrdovicianDarriwilianLlanvirnLlandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn458.4
Abereiddian/Early Llanvirn461.3 *
Dapingian467.3
ArenigFennian468.4 *
Early OrdovicianFloian470
Whitlandian471.1 *
Moridunian474.3 *
TremadocianTremadocMigneintian477.7
Cressagian480.8 *
485 *