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
  • 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. Kretzoi. 1942. Necroteuthis n. g. (Ceph. Dibr., Necroteuthidae N. F.) aus dem Oligozän von Budapest und das system der Dibranchiata. Földtani Közlöny 72:125-238 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 126689 collections

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International Chronostratigraphic TimescaleTen Million Year BinsOrdovician of BritainOrdovician of North AmericaCambrian of ChinaCambrian of West AvaloniaCarbo-Permian of the Russian PlatformPermian of the Russian PlatformObsolete Names for ICS Units
QuaternaryHoloceneMeghalayanCenozoic 60
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate Pleistocene0.0117
Chibanian0.129
Calabrian0.774
Gelasian1.8
NeogenePliocenePiacenzianTertiary †2.58
Zanclean3.6
MioceneMessinian5.333
Tortonian7.246
SerravallianCenozoic 511.63
Langhian13.82
Burdigalian15.98
Aquitanian20.44
PaleogeneOligoceneChattianCenozoic 423.03
Rupelian27.82
EocenePriabonianCenozoic 333.9
Bartonian37.71
LutetianCenozoic 241.2
Ypresian47.8
PaleoceneThanetianCenozoic 156
Selandian59.2
Danian61.6
CretaceousLate CretaceousMaastrichtianCretaceous 866
CampanianCretaceous 772.1
SantonianCretaceous 683.6
Coniacian86.3
Turonian89.8
CenomanianCretaceous 593.9
Early CretaceousAlbianCretaceous 4100.5
AptianCretaceous 3113
BarremianCretaceous 2121.4
Hauterivian125.77
ValanginianCretaceous 1132.6
Berriasian139.8
JurassicLate JurassicTithonianJurassic 6145
KimmeridgianJurassic 5149.2
Oxfordian154.8
Middle JurassicCallovian161.5
BathonianJurassic 4165.3
Bajocian168.2
AalenianJurassic 3170.9
Early JurassicToarcian174.7
PliensbachianJurassic 2184.2
SinemurianJurassic 1192.9
Hettangian199.5
TriassicLate TriassicRhaetianTriassic 4201.4
Norian208.5
CarnianTriassic 3227
Middle TriassicLadinianTriassic 2237
Anisian242
Early TriassicOlenekianTriassic 1247.2
Induan251.2
PermianLopingianChanghsingianPermian 4Melekhovian251.902
WuchiapingianLongtanian †254.14
TatarianVyatkian256.8 *
GuadalupianCapitanianSeverodvinian259.51
WordianUrzhumian264.28
Noginskian264.9 *
RoadianPermian 3KazanianPovolzhian266.9
Sokian270.7 *
CisuralianKungurianPermian 2KungurianIrenian/Ufimian273.01
Filipovian276.5 *
Pavlovoposadian276.8 *
Saraninian280.1 *
ArtinskianArtinskianSarginian283.5
Irginian285.9 *
Rusavkinian287.6 *
Burtsevian287.8 *
SakmarianSakmarianSterlitamakian290.1
Tastubian291.7 *
AsselianPermian 1AsselianShikhanian293.52
Uskalykian294.8
Surenian297.5
CarboniferousPennsylvanianGzhelianCarboniferous 5298.9
KasimovianDorogomilovian303.7
Khamovnikian304.8
Krevyakinian305.8 *
MoscovianCarboniferous 4Myachkovian307
Podolskian308.9 *
Kashirian311.4 *
Vereian313.8
Melekessian314.8
Bashkirian315.2
Cheremshanian316.9 *
Prikamian318.6 *
Severokeltmian319.9 *
Krasnopolyanian321.2 *
Voznesenian321.9 *
MississippianSerpukhovianCarboniferous 3Zapaltjubian323.2
Protvian324.4 *
Steshevian326.8 *
Tarusian329 *
ViseanCarboniferous 2Venevian330.9
Mikhailovian331.9 *
Aleksinian333.7 *
Tulian335.8 *
Bobrikian339.9 *
Radaevkian343.4 *
TournaisianCarboniferous 1Kosvian346.7
Kizelian350.7 *
Cherepetian351.9 *
Karakubian354.4 *
Upinian356.3 *
Malevkian357.6 *
Gumerovian358 *
DevonianLate DevonianFamennianDevonian 5358.9
FrasnianDevonian 4372.2
Middle DevonianGivetianDevonian 3382.7
Eifelian387.7
Early DevonianEmsianDevonian 2393.3
PragianDevonian 1407.6
Lochkovian410.8
SilurianPridoliSilurian 2419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychianSilurian 1433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianOrdovician 5AshgillHirnantianCincinnatianGamachian443.8
KatianRawtheyan445.2
Richmondian446 *
Cautleyan448.9 *
Pusgillian449.3 *
CaradocStreffordianOnnian †449.6 *
MaysvillianRocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian449.8 *
Edenian450.4 *
MohawkianChatfieldian451.1 *
Cheneyan451.5 *
Burrellian452.7 *
SandbianOrdovician 4453
Actonian †453.2 *
Turinian453.7 *
Marshbrookian †Woolstonian †454.2 *
Longvillian †455.2 *
Aurelucian456.8 *
WhiterockianCanadian †Chazyan †/Marmor457 *
Soudleyan †/Harnagian/Costonian457.4 *
Middle OrdovicianDarriwilianOrdovician 3LlanvirnLlandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn458.4
Abereiddian/Early Llanvirn461.3 *
DapingianOrdovician 2467.3
ArenigFennian468.4 *
Rangerian469.1 *
Early OrdovicianFloianIbexianBlackhillsianJeffersonian †Cassinian †470
Whitlandian471.1 *
Tulean473.9 *
Moridunian474.3 *
TremadocianOrdovician 1TremadocMigneintian477.7
Stairsian480.3 *
Cressagian480.8 *
SkullrockianDemingian †482 *
485 *
CambrianFurongianStage 10Cambrian 5NiucheheanTaoyuanian †485.4
487.5
JiangshanianJiangshanian489.5
PaibianPaibian494
Waergangian †/Youshuanian494.9 *
MiaolingianGuzhangianCambrian 4GuzhangianWangcunian †Series 3 †497
Arcadian498.4
DrumianDrumian500.5
WuliuanCambrian 3Wuliuan/TaijangianStage 5 †504.5
Series 2Stage 4DuyunianBranchian509
Stage 3Cambrian 2Nangaoian514
Placentian517.1
TerreneuvianStage 2Meishucunian521
FortunianCambrian 1529
Jinnigian530.7
538.8