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. 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. 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
  • 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
  • J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 view
  • P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 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 125964 collections

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International Chronostratigraphic TimescaleNorth American Mammal Subages/ZonesSouth American Land Mammal AgesObsolete Names for ICS UnitsPaleogene Mammal Ages of AsiaCenozoic Subepochs of Southern EuropeCambrian of KazakhstanCambrian of West Avalonia
QuaternaryHoloceneMeghalayan0
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate PleistoceneSheridanianLujanianTarantian0.0117
ChibanianIonian0.129
Cudahyan/Sappan0.21
Ensenadan0.3 *
Calabrian0.774
Senecan/Rexroadian1.4
SanandresianUquian †1.7 *
Gelasian1.8
NeogenePliocenePiacenzianVorohueanTertiary †2.58
Chapadmalalan2.9 *
Zanclean3.6
Montehermosan3.7 *
Late Hemphillian/late Early Hemphillian/early Early Hemphillian4.7
Huayquerian4.9 *
MioceneMessinian5.333
Tortonian7.246
Chasicoan7.9 *
Late Clarendonian/Early Clarendonian9.4
Mayoan9.9 *
Laventan10.9 *
Serravallian11.63
late Late Barstovian/early Late Barstovian/Early Barstovian12.5
Colloncuran13.7 *
Langhian13.82
Friasian15.4 *
Burdigalian15.98
Santacrucian16.2 *
Late Hemingfordian/Early Hemingfordian16.3
Colhuehuapian17.4 *
late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonian18.5
Aquitanian20.44
Deseadan20.9 *
PaleogeneOligoceneChattianTabenbulakianHsandagolian23.03
Monroecreekian23.1 *
Geringian24.7 *
RupelianKekeamuan27.82
Tinguirirican28.9 *
29.5
EocenePriabonianLate Chadronian/Middle Chadronian/Early ChadronianHouldjinian/Ergilian/Ulangochuian33.9
Divisaderan35.9 *
37
BartonianSharamurunian/Irdinmanhan/Arshantan37.71
Late Uintan/Early Uintan39.7
Lutetian41.2
Mustersan41.9 *
Twinbuttean/Blacksforkian/Gardnerbuttian46.2
YpresianBumbanian47.8
Casamayoran47.9 *
Lostcabinian/Lysitean/Graybullian/Sandcouleean50.5
Cf3/Cf2/Cf154.9
PaleoceneThanetianRiochicanGashatan56
Ti6/Ti5/Ti4/Ti3/Ti2/Ti156.2
Itaboraian56.9 *
Peligran58.9 *
Selandian59.2
To3/To2/To160.9
Danian61.6
Tiupampan62.4 *
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 OrdovicianHirnantian443.8
Katian445.2
Sandbian453
Middle OrdovicianDarriwilian458.4
Dapingian467.3
Early OrdovicianFloian470
TremadocianUngurian477.7
CambrianFurongianStage 10Batyrbaian485.4
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Paibian494
MiaolingianGuzhangianSeries 3 †Ayusokkanian497
Arcadian498.4
499.5
DrumianZhanaarykian500.5
Tuesaian503
WuliuanStage 5 †504.5
505.3
Series 2Stage 4Branchian509
Toyonian510 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
Placentian517.1
TerreneuvianStage 2Tommotian521
525.5
Fortunian529
538.8