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
  • 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
  • F. M. Gradstein, F. P. Agterberg, J. G. Ogg, J. Hardenbol, P. Van Veen, J. Thierry, and Z. Huang. 1995. A Triassic, Jurassic, and Cretaceous time scale. SEPM Special Publication 54 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • A. G. Sennikov and V. K. Golubev. 2006. Vyazniki Biotic Assemblage of the Terminal Permian. Paleontological Journal 40(suppl. 4):S475-S481 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 127057 collections

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International Chronostratigraphic TimescalePermian Subages of GermanyAmmonite Chrons of North AmericaOrdovician of Ibero-BohemiaMesozoic SubagesCenozoic SubepochsCambrian of BritainDevonian of Eastern North AmericaPermo-Triassic Subages of Eastern EuropeObsolete Carboniferous Ages of China
QuaternaryPleistoceneLate PleistoceneLate Pleistocene0.0117
ChibanianMiddle Pleistocene0.129
CalabrianEarly Pleistocene0.774
Gelasian1.8
NeogenePliocenePiacenzianLate Pliocene2.58
ZancleanEarly Pliocene3.6
MioceneMessinianLate Miocene5.333
Tortonian7.246
SerravallianMiddle Miocene11.63
Langhian13.82
BurdigalianEarly Miocene15.98
Aquitanian20.44
PaleogeneOligoceneChattianLate Oligocene23.03
RupelianEarly Oligocene27.82
EocenePriabonianLate Eocene33.9
BartonianMiddle Eocene37.71
Lutetian41.2
YpresianEarly Eocene47.8
PaleoceneThanetianLate Paleocene56
SelandianMiddle Paleocene59.2
DanianEarly Paleocene61.6
CretaceousLate CretaceousMaastrichtianLate Maastrichtian/Early Maastrichtian66
CampanianLate Campanian/Middle Campanian/Early Campanian72.1
SantonianLate Santonian/Middle Santonian/Early Santonian83.6
ConiacianLate Coniacian/Middle Coniacian/Early Coniacian86.3
TuronianLate Turonian/Middle Turonian/Early Turonian89.8
CenomanianLate Cenomanian/Middle Cenomanian/Early Cenomanian93.9
Early CretaceousAlbianLate Albian100.5
Middle Albian106.2 *
Early Albian109.9 *
AptianLate Aptian113
Early Aptian119.5 *
BarremianLate Barremian/Early Barremian121.4
HauterivianLate Hauterivian/Early Hauterivian125.77
ValanginianLate Valanginian/Early Valanginian132.6
BerriasianLate Berriasian139.8
Middle Berriasian140.6 *
Early Berriasian142.7 *
JurassicLate JurassicTithonianLate TithonianMiddle Tithonian145
Early Tithonian146.3 *
KimmeridgianLate Kimmeridgian149.2
Early Kimmeridgian152.2 *
OxfordianLate OxfordianMiddle Oxfordian/Early Oxfordian154.8
157.9 *
Middle JurassicCallovianLate Callovian/Middle Callovian/Early Callovian161.5
BathonianLate Bathonian/Middle Bathonian/Early Bathonian165.3
BajocianEpizigzagicerasLate Bajocian168.2
Rotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense168.4
Early Bajocian168.6 *
AalenianHowelli/Scissum/WestermanniLate Aalenian/Middle Aalenian/Early Aalenian170.9
Early JurassicToarcianYakounensis/Hillebrandti/CrassicostaLate Toarcian174.7
Planulata179.3 *
Arnioceras arnouldi179.8 *
Middle Toarcian180.4 *
Kanense181.3 *
Carlottense182.3 *
Early Toarcian182.9 *
Kunae183.5 *
PliensbachianLate Pliensbachian/Early Pliensbachian184.2
Freboldi185.1 *
Whiteavesi/ImlayiTetraspidoceras186.2 *
189.2 *
Plesechioceras harbledownense/Asteroceras varians/CoronicerasCanadensis190.3 *
SinemurianLate Sinemurian/Early Sinemurian192.9
PseudaetomocerasPsiloceras196.4 *
Franziceras/Euphyllites196.5 *
HettangianLate Hettangian/Middle Hettangian/Early Hettangian199.5
TriassicLate TriassicRhaetian201.4
NorianSevatian208.5
Alaunian213.2 *
Lacian216.7 *
CarnianTuvalian227
Julian233.4 *
Middle TriassicLadinianLongobardian237
Fassanian239.7 *
AnisianIllyrian242
Pelsonian243.8 *
Bithynian244.7 *
Aegean245.5 *
Early TriassicOlenekianSpathianVokhmian247.2
Smithian248.9 *
InduanDienerian251.2
Griesbachian251.4 *
PermianLopingianChanghsingianBuntsandstein251.902
WuchiapingianLate Vyatkian/Early Vyatkian254.14
GuadalupianCapitanianOhre/AllerLate Severodvinian/Early Severodvinian259.51
WordianLeineLate Urzhumian/Early Urzhumian264.28
RoadianLate Kazanian/Early Kazanian266.9
CisuralianKungurian273.01
Artinskian283.5
Sakmarian290.1
Asselian293.52
CarboniferousPennsylvanianGzhelianMapingian †298.9
Kasimovian303.7
305.9
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennianConewangan/Conneautan/Canadaway358.9
FrasnianWest Fallsian/Sonyean372.2
Middle DevonianGivetianGeneseean/Taghanican/TioughnioganCazenovian382.7
EifelianSouthwoodian387.7
Early DevonianEmsianSawkillian/Deer ParkianHelderbergian393.3
Pragian407.6
Lochkovian410.8
SilurianPridoli419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychian433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianKosovian443.8
KatianKralodvorianBohdalec †445.2
Berounian449.7 *
Sandbian453
Zahorany †/ViniceLetna †456.2 *
Liben †458 *
Middle OrdovicianDarriwilian458.4
Dobrotivian458.5 *
Oretanian459.7 *
Sarka †461.7 *
DapingianKlabava †467.3
Arenigian468
Early OrdovicianFloian470
TremadocianTremadocian477.7
CambrianFurongianStage 10MerionethDolgellian/Trempealeauan485.4
Festiniogian489.2 *
Jiangshanian489.5
Maentwrogian493.1 *
Paibian494
MiaolingianGuzhangianSt Davids497
Drumian500.5
Wuliuan504.5
Series 2Stage 4Caerfai509
Stage 3514
TerreneuvianStage 2521
Fortunian529
538.8