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, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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
  • 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, 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
  • 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

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 126762 collections

Show more time

Show linear time

International Chronostratigraphic TimescaleAmmonite Chrons of North AmericaDevonian of Eastern North AmericaNorth American Land Mammal AgesTen Million Year BinsDevonian of CzechoslovakiaCarboniferous SubepochsOrdovician of BritainCenozoic Subepochs of Southern EuropeCambrian of North America
QuaternaryHoloceneMeghalayanSaintaugustineanCenozoic 60
Santarosean0.0004
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate PleistoceneTarantian0.0117
Rancholabrean0.014
ChibanianIonian0.129
Irvingtonian0.21
Calabrian0.774
Blancan1.4
Gelasian1.8
NeogenePliocenePiacenzian2.58
Zanclean3.6
Hemphillian4.7
MioceneMessinian5.333
Tortonian7.246
Clarendonian9.4
SerravallianCenozoic 511.63
Barstovian12.5
Langhian13.82
Burdigalian15.98
Hemingfordian16.3
Arikareean18.5
Aquitanian20.44
PaleogeneOligoceneChattianCenozoic 423.03
Rupelian27.82
Whitneyan29.5
Orellan31.8
EocenePriabonianChadronianCenozoic 333.9
Duchesnean37
Bartonian37.71
Uintan39.7
LutetianCenozoic 241.2
Bridgerian46.2
Ypresian47.8
Wasatchian50.5
Clarkforkian54.9
PaleoceneThanetianCenozoic 156
Tiffanian56.2
Selandian59.2
Torrejonian60.9
Danian61.6
Puercan63.8
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
BajocianEpizigzagiceras168.2
Rotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense168.4
AalenianHowelli/Scissum/WestermanniJurassic 3170.9
Early JurassicToarcianYakounensis/Hillebrandti/Crassicosta174.7
Planulata179.3 *
Arnioceras arnouldi179.8 *
Kanense181.3 *
Carlottense182.3 *
Kunae183.5 *
PliensbachianJurassic 2184.2
Freboldi185.1 *
Whiteavesi/ImlayiTetraspidoceras186.2 *
189.2 *
Plesechioceras harbledownense/Asteroceras varians/CoronicerasCanadensis190.3 *
SinemurianJurassic 1192.9
PseudaetomocerasPsiloceras196.4 *
Franziceras/Euphyllites196.5 *
Hettangian199.5
TriassicLate TriassicRhaetianTriassic 4201.4
Norian208.5
CarnianTriassic 3227
Middle TriassicLadinianTriassic 2237
Anisian242
Early TriassicOlenekianTriassic 1247.2
Induan251.2
PermianLopingianChanghsingianPermian 4251.902
Wuchiapingian254.14
GuadalupianCapitanian259.51
Wordian264.28
RoadianPermian 3266.9
CisuralianKungurianPermian 2273.01
Artinskian283.5
Sakmarian290.1
AsselianPermian 1293.52
CarboniferousPennsylvanianGzhelianCarboniferous 5Late Pennsylvanian298.9
Kasimovian303.7
MoscovianCarboniferous 4Middle Pennsylvanian307
BashkirianEarly Pennsylvanian315.2
MississippianSerpukhovianCarboniferous 3Late Mississippian323.2
ViseanCarboniferous 2Middle Mississippian330.9
TournaisianCarboniferous 1Early Mississippian346.7
DevonianLate DevonianFamennianConewangan/Conneautan/CanadawayDevonian 5358.9
FrasnianWest Fallsian/SonyeanDevonian 4372.2
Middle DevonianGivetianGeneseean/Taghanican/TioughnioganCazenovianDevonian 3Srbsko382.7
EifelianSouthwoodianChotec387.7
Early DevonianEmsianSawkillian/Deer ParkianHelderbergianDevonian 2Daleje/Zlichovian393.3
PragianDevonian 1Pragian407.6
LochkovianLochkovian410.8
SilurianPridoliSilurian 2419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychianSilurian 1433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianOrdovician 5AshgillHirnantian443.8
KatianRawtheyan445.2
Cautleyan448.9 *
Pusgillian449.3 *
CaradocStreffordianOnnian †449.6 *
Cheneyan451.5 *
Burrellian452.7 *
SandbianOrdovician 4453
Actonian †453.2 *
Marshbrookian †Woolstonian †454.2 *
Longvillian †455.2 *
Aurelucian456.8 *
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 *
Early OrdovicianFloian470
Whitlandian471.1 *
Moridunian474.3 *
TremadocianOrdovician 1TremadocMigneintian477.7
Cressagian480.8 *
485 *
CambrianFurongianStage 10Cambrian 5Franconian †/Dresbachian/Millardan485.4
Sunwaptan487.5
Jiangshanian489.5
Steptoean493 *
Paibian494
MiaolingianGuzhangianCambrian 4MarjumianAlbertian †497
Drumian500.5
WuliuanCambrian 3Topazan504.5
Delamaran506.5
Series 2Stage 4Waucoban †509
Dyeran511 *
Stage 3Cambrian 2514
Montezuman514.8 *
Begadean519.9 *
TerreneuvianStage 2521
FortunianCambrian 1529
538.8