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
  • 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
  • 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 128057 collections

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International Chronostratigraphic TimescaleOrdovician of BritainPermian Subages of GermanyPermian of ChinaOrdovician of the BalticDevonian of GermanyCarbo-Permian of the Russian Platform
PermianLopingianChanghsingianBuntsandsteinMeishanianMelekhovian251.902
Baoqingian253.4 *
WuchiapingianLaoshanian254.14
Laibinian257.7 *
GuadalupianCapitanianOhre/AllerLengwuan259.51
WordianLeineKuhfengian264.28
Noginskian264.9 *
Roadian266.9
CisuralianKungurianLuodianian273.01
Pavlovoposadian276.8 *
Artinskian283.5
Longlinian285.4 *
Rusavkinian287.6 *
Sakmarian290.1
AsselianZisongian293.52
CarboniferousPennsylvanianGzhelian298.9
300.1
KasimovianDorogomilovian303.7
Khamovnikian304.8
Krevyakinian305.8 *
MoscovianMyachkovian307
Podolskian308.9 *
Kashirian311.4 *
Vereian313.8
Melekessian314.8
Bashkirian315.2
Cheremshanian316.9 *
Prikamian318.6 *
Severokeltmian319.9 *
Krasnopolyanian321.2 *
Voznesenian321.9 *
MississippianSerpukhovianZapaltjubian323.2
Protvian324.4 *
Steshevian326.8 *
Tarusian329 *
ViseanVenevian330.9
Mikhailovian331.9 *
Aleksinian333.7 *
Tulian335.8 *
Bobrikian339.9 *
Radaevkian343.4 *
TournaisianKosvian346.7
Kizelian350.7 *
Cherepetian351.9 *
Karakubian354.4 *
Upinian356.3 *
Malevkian357.6 *
Gumerovian358 *
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 OrdovicianHirnantianAshgillHirnantianHarjuPorkuni443.8
KatianRawtheyanPirgu445.2
Cautleyan448.9 *
Pusgillian449.3 *
CaradocStreffordianOnnian †Vormsi449.6 *
NabalaJohvi †450 *
ViruRakvere450.6 *
Cheneyan451.5 *
Oandu452 *
Burrellian452.7 *
SandbianKeilaIdavere †453
Actonian †453.2 *
Haljala453.9
Marshbrookian †Woolstonian †454.2 *
Longvillian †455.2 *
Kukruse456.4 *
Aurelucian456.8 *
Soudleyan †/Harnagian/Costonian457.4 *
UhakuAluoja †457.5 *
Middle OrdovicianDarriwilianLlanvirnLlandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn458.4
Lasnamagi458.9 *
Aseri460.4 *
Abereiddian/Early Llanvirn461.3 *
OelandKunda462.9 *
Valaste †/Hunderum464.3 *
VolkhovLangevoja †/Vaana/Saka467.1 *
Dapingian467.3
ArenigFennian468.4 *
Billingen469.3 *
Early OrdovicianFloian470
Latorp †470.1 *
Whitlandian471.1 *
Hunneberg473.7 *
Moridunian474.3 *
TremadocianTremadocMigneintian477.7
Cressagian480.8 *
Varangu481.3 *
Pakerort482.2 *
485 *
CambrianFurongianStage 10485.4
486.3 *
486.5