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
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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
  • J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 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 126934 collections

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International Chronostratigraphic TimescaleSilurian of EnglandCambrian of KazakhstanDevonian of CzechoslovakiaPermian of the Salt RangeDevonian of GermanyOrdovician of BritainNorth American Land Mammal AgesCambrian of West AvaloniaPaleogene Mammal Ages of AsiaOrdovician of Ibero-Bohemia
QuaternaryHoloceneMeghalayanSaintaugustinean0
Santarosean0.0004
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate Pleistocene0.0117
Rancholabrean0.014
Chibanian0.129
Irvingtonian0.21
Calabrian0.774
Blancan1.4
Gelasian1.8
NeogenePliocenePiacenzian2.58
Zanclean3.6
Hemphillian4.7
MioceneMessinian5.333
Tortonian7.246
Clarendonian9.4
Serravallian11.63
Barstovian12.5
Langhian13.82
Burdigalian15.98
Hemingfordian16.3
Arikareean18.5
Aquitanian20.44
PaleogeneOligoceneChattianTabenbulakianHsandagolian23.03
RupelianKekeamuan27.82
Whitneyan29.5
Orellan31.8
EocenePriabonianChadronianHouldjinian/Ergilian/Ulangochuian33.9
Duchesnean37
BartonianSharamurunian/Irdinmanhan/Arshantan37.71
Uintan39.7
Lutetian41.2
Bridgerian46.2
YpresianBumbanian47.8
Wasatchian50.5
Clarkforkian54.9
PaleoceneThanetianGashatan56
Tiffanian56.2
Selandian59.2
Torrejonian60.9
Danian61.6
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
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
Kathwai251.5 *
PermianLopingianChanghsingian251.902
252.4 *
Chhidru252.9 *
Wuchiapingian254.14
Kalabagh255 *
Wargal256 *
GuadalupianCapitanian259.51
Wordian264.28
265.3 *
Amb266.1 *
Roadian266.9
270.7 *
CisuralianKungurian273.01
Artinskian283.5
Sakmarian290.1
Asselian293.52
CarboniferousPennsylvanianGzhelian298.9
Kasimovian303.7
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennianWocklum/Dasberg/Hemberg/Nehden358.9
FrasnianAdorf372.2
Middle DevonianGivetianSrbskoGivetian382.7
EifelianChotecEifelian387.7
Early DevonianEmsianDaleje/ZlichovianEmsian393.3
PragianPragianSiegen407.6
LochkovianLochkovianGedinnine410.8
SilurianPridoliRed Downtonian/Temeside Shales/Downton CastleWhitcliffe/Leintwardine419.2
Bringewood/Elton421.3
LudlowLudfordianCoalbrookdaleWenlock (England)/Tickwood423
Gorstian425.6
Buildwas426.4 *
WenlockHomerian427.4
WychWoolhope428.4 *
Sheinwoodian430.5
LlandoveryTelychian433.4
436.3 *
Aeronian438.5
Cowleigh Park439.3 *
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianAshgillHirnantianKosovian443.8
KatianRawtheyanKralodvorianBohdalec †445.2
Cautleyan448.9 *
Pusgillian449.3 *
CaradocStreffordianOnnian †449.6 *
Berounian449.7 *
Cheneyan451.5 *
Burrellian452.7 *
Sandbian453
Actonian †453.2 *
Marshbrookian †Woolstonian †454.2 *
Longvillian †455.2 *
Zahorany †/ViniceLetna †456.2 *
Aurelucian456.8 *
Soudleyan †/Harnagian/Costonian457.4 *
Liben †458 *
Middle OrdovicianDarriwilianLlanvirnLlandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn458.4
Dobrotivian458.5 *
Oretanian459.7 *
Abereiddian/Early Llanvirn461.3 *
Sarka †461.7 *
DapingianKlabava †467.3
Arenigian468
ArenigFennian468.4 *
Early OrdovicianFloian470
Whitlandian471.1 *
Moridunian474.3 *
TremadocianUngurianTremadocMigneintianTremadocian477.7
Cressagian480.8 *
485 *
CambrianFurongianStage 10Batyrbaian485.4
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Paibian494
MiaolingianGuzhangianAyusokkanian497
Arcadian498.4
499.5
DrumianZhanaarykian500.5
Tuesaian503
Wuliuan504.5
505.3
Series 2Stage 4Branchian509
Toyonian510 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
Placentian517.1
TerreneuvianStage 2Tommotian521
525.5
Fortunian529
538.8