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
  • B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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
  • 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

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 126778 collections

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International Chronostratigraphic TimescaleOrdovician of ChinaCambrian of ChinaPermo-Triassic Subages of Eastern EuropeCambrian of KazakhstanPermian of North AmericaSilurian Ages of EuropeCarboniferous of North AmericaPermian of the Salt Range
TriassicEarly TriassicOlenekianVokhmian247.2
Induan251.2
Kathwai251.5 *
PermianLopingianChanghsingian251.902
252.4 *
Chhidru252.9 *
WuchiapingianLate Vyatkian/Early Vyatkian254.14
Kalabagh255 *
Wargal256 *
GuadalupianCapitanianLate Severodvinian/Early SeverodvinianCapitanian259.51
WordianLate Urzhumian/Early UrzhumianWordian264.28
265.3 *
Amb266.1 *
RoadianLate Kazanian/Early KazanianRoadian266.9
270.7 *
CisuralianKungurianLeonardianCathedralian273.01
Hessian281.9 *
Artinskian283.5
WolfcampianLenoxian286.1 *
Sakmarian290.1
AsselianNealianBursumian †293.52
CarboniferousPennsylvanianGzhelianVirgilian298.9
KasimovianMissourian303.7
Desmoinesian305.9 *
Moscovian307
Atokan312.7 *
Bashkirian315.2
Morrowan318.4 *
MississippianSerpukhovianChesterian323.2
Visean330.9
Meramecian335.8 *
Osagean343.1 *
Tournaisian346.7
Kinderhookian351.9 *
DevonianLate DevonianFamennian358.9
Frasnian372.2
Middle DevonianGivetian382.7
Eifelian387.7
Early DevonianEmsian393.3
Pragian407.6
Lochkovian410.8
SilurianPridoli419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerianGleedonian427.4
Whitwellian429.7 *
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
TremadocianXinchangianUngurian477.7
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