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
  • 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. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 view
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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 TimescaleAmmonite Chrons of North AmericaDevonian of GermanyCretaceous North American Land-Mammal AgesCambrian of ChinaCambrian of KazakhstanPermian of the Salt RangePermian of the PamirsAmmonite Chrons of Northwest EuropeOrdovician of China
CretaceousLate CretaceousMaastrichtianLancian/Edmontonian66
CampanianJudithian/Aquilan72.1
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
BajocianEpizigzagicerasParkinsoni/Garantiana/Subfurcatum/Sauzei/Laeviuscula/Discites168.2
Rotundum/Oblatum/Kirschneri/Crassicostatus/WidebayenseHumphresianum168.4
AalenianHowelli/Scissum/WestermanniConcavum/Murchisonae/Opalinum170.9
Early JurassicToarcianYakounensis/Hillebrandti/CrassicostaLevesquei/Variabilis/BifronsThouarsense174.7
Planulata179.3 *
Arnioceras arnouldi179.8 *
180.1
Kanense181.3 *
Serpentinum/Falciferum/Tenuicostatum182
Carlottense182.3 *
Kunae183.5 *
PliensbachianSpinatum/Margaritatus/Davoei/Ibex/Jamesoni184.2
Freboldi185.1 *
Whiteavesi/ImlayiTetraspidoceras186.2 *
189.2 *
Plesechioceras harbledownense/Asteroceras varians/CoronicerasCanadensis190.3 *
SinemurianRaricostatum/Oxynotum/Obtusum/Turneri/Semicostatum/Bucklandi192.9
PseudaetomocerasPsiloceras196.4 *
Franziceras/Euphyllites196.5 *
HettangianAngulata/Liasicus/Planorbis199.5
TriassicLate TriassicRhaetian201.4
Norian208.5
Carnian227
Middle TriassicLadinian237
Anisian242
Early TriassicOlenekian247.2
Induan251.2
Kathwai251.5 *
PermianLopingianChanghsingianDorashamian251.902
252.4 *
Chhidru252.9 *
WuchiapingianDzhulfian254.14
Kalabagh255 *
Wargal256 *
GuadalupianCapitanianMidian259.51
Wordian264.28
265.3 *
Amb266.1 *
Murgabian266.2 *
Roadian266.9
270.7 *
CisuralianKungurianKubergandian273.01
Bolorian279.8
Artinskian283.5
Yakhtashian286
SakmarianSakmarian290.1
AsselianAsselian293.52
CarboniferousPennsylvanianGzhelian298.9
Kasimovian303.7
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennianWocklum/Dasberg/Hemberg/Nehden358.9
FrasnianAdorf372.2
Middle DevonianGivetianGivetian382.7
EifelianEifelian387.7
Early DevonianEmsianEmsian393.3
PragianSiegen407.6
LochkovianGedinnine410.8
SilurianPridoli419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychian433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianHirnantianXiaoxita †/ShikouWufeng †443.8
KatianChientangkiangian445.2
Neichianshanian/Hanjiang449.5
Sandbian453
Middle OrdovicianDarriwilianDarriwilianGuniu †/Hulo458.4
Hunjiang †Dawan †/Daobaowan/Ningkuo466.3 *
DapingianDapingian467.3
Early OrdovicianFloianYiyangian470
TremadocianUngurianXinchangian477.7
Lianghekou †477.9 *
CambrianFurongianStage 10NiucheheanTaoyuanian †Batyrbaian485.4
JiangshanianJiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
PaibianPaibian494
Waergangian †/Youshuanian494.9 *
MiaolingianGuzhangianGuzhangianWangcunian †Ayusokkanian497
499.5
DrumianDrumianZhanaarykian500.5
Tuesaian503
WuliuanWuliuan/Taijangian504.5
505.3
Series 2Stage 4Duyunian509
Toyonian510 *
Botomian512.5 *
Stage 3Nangaoian514
Atdabanian515.6 *
TerreneuvianStage 2MeishucunianTommotian521
525.5
Fortunian529
Jinnigian530.7
538.8