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
  • A. G. Sennikov and V. K. Golubev. 2006. Vyazniki Biotic Assemblage of the Terminal Permian. Paleontological Journal 40(suppl. 4):S475-S481 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
  • 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 126849 collections

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International Chronostratigraphic TimescalePermian of Western EuropePermo-Triassic Subages of Eastern EuropePermian of the PamirsCambrian of KazakhstanCarboniferous SubepochsOrdovician of ChinaOrdovician of the BalticSilurian of the Baltic
TriassicEarly TriassicOlenekianVokhmian247.2
Induan251.2
PermianLopingianChanghsingianDorashamian251.902
WuchiapingianZechsteinLate Vyatkian/Early VyatkianDzhulfian254.14
GuadalupianCapitanianRotliegendesLate Severodvinian/Early SeverodvinianMidian259.51
WordianLate Urzhumian/Early Urzhumian264.28
Murgabian266.2 *
RoadianLate Kazanian/Early Kazanian266.9
CisuralianKungurianKubergandian273.01
Bolorian279.8
ArtinskianAutunian283.5
Yakhtashian286
SakmarianSakmarian290.1
AsselianAsselian293.52
CarboniferousPennsylvanianGzhelianLate Pennsylvanian298.9
Kasimovian303.7
MoscovianMiddle Pennsylvanian307
BashkirianEarly Pennsylvanian315.2
MississippianSerpukhovianLate Mississippian323.2
ViseanMiddle Mississippian330.9
TournaisianEarly Mississippian346.7
DevonianLate DevonianFamennian358.9
Frasnian372.2
Middle DevonianGivetian382.7
Eifelian387.7
Early DevonianEmsian393.3
Pragian407.6
Lochkovian410.8
SilurianPridoliOhesaare419.2
Kaugetuma421.7 *
LudlowLudfordianKuressaare423
Paadla423.4 *
Gorstian425.6
WenlockHomerianRootsikula427.4
Jaagarahu429.2 *
Sheinwoodian430.5
Jaani431.8 *
LlandoveryTelychian433.4
Adavere434 *
Aeronian438.5
Raikkula439.4 *
Rhuddanian440.8
Juuru441.4 *
OrdovicianLate OrdovicianHirnantianHirnantianXiaoxita †/ShikouWufeng †HarjuPorkuni443.8
KatianChientangkiangianPirgu445.2
Neichianshanian/Hanjiang449.5
Vormsi449.6 *
NabalaJohvi †450 *
ViruRakvere450.6 *
Oandu452 *
SandbianKeilaIdavere †453
Haljala453.9
Kukruse456.4 *
UhakuAluoja †457.5 *
Middle OrdovicianDarriwilianDarriwilianGuniu †/Hulo458.4
Lasnamagi458.9 *
Aseri460.4 *
OelandKunda462.9 *
Valaste †/Hunderum464.3 *
Hunjiang †Dawan †/Daobaowan/Ningkuo466.3 *
VolkhovLangevoja †/Vaana/Saka467.1 *
DapingianDapingian467.3
Billingen469.3 *
Early OrdovicianFloianYiyangian470
Latorp †470.1 *
Hunneberg473.7 *
TremadocianUngurianXinchangian477.7
Lianghekou †477.9 *
Varangu481.3 *
Pakerort482.2 *
CambrianFurongianStage 10Batyrbaian485.4
486.3 *
486.5
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Paibian494
MiaolingianGuzhangianAyusokkanian497
499.5
DrumianZhanaarykian500.5
Tuesaian503
Wuliuan504.5
505.3
Series 2Stage 4509
Toyonian510 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
TerreneuvianStage 2Tommotian521
525.5