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
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 128152 collections

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International Chronostratigraphic TimescaleOrdovician of BritainDevonian of GermanyOrdovician of Ibero-BohemiaCambrian of AustraliaObsolete Carboniferous Ages of China
CarboniferousPennsylvanianGzhelianMapingian †298.9
Kasimovian303.7
305.9
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 OrdovicianHirnantianAshgillHirnantianKosovian443.8
KatianRawtheyanKralodvorianBohdalec †445.2
Cautleyan448.9 *
Pusgillian449.3 *
CaradocStreffordianOnnian †449.6 *
Berounian449.7 *
Cheneyan451.5 *
Burrellian452.7 *
Sandbian453
Actonian †453.2 *
Marshbrookian †Woolstonian †454.2 *
Longvillian †455.2 *
Zahorany †/ViniceLetna †456.2 *
Aurelucian456.8 *
Soudleyan †/Harnagian/Costonian457.4 *
Liben †458 *
Middle OrdovicianDarriwilianLlanvirnLlandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn458.4
Dobrotivian458.5 *
Oretanian459.7 *
Abereiddian/Early Llanvirn461.3 *
Sarka †461.7 *
DapingianKlabava †467.3
Arenigian468
ArenigFennian468.4 *
Early OrdovicianFloian470
Whitlandian471.1 *
Moridunian474.3 *
TremadocianTremadocMigneintianTremadocian477.7
Cressagian480.8 *
485 *
CambrianFurongianStage 10Datsonian485.4
Payntonian486.8 *
JiangshanianIverian489.5
PaibianIdamean494
MiaolingianGuzhangianMindyallan497
Boomerangian499
DrumianUndillan500.5
Floran503
WuliuanTempletonian504.5
Ordian507.8 *
Series 2Stage 4509
510.8 *