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
  • J. I. Raine, A. G. Beu, A. F. Boyes, H. J. Campbell, R. A. Cooper, J. S. Crampton, M. P. Crundwell, C. J. Hollis, and H. E. G. Morgans. 2015. Revised Calibration of the New Zealand Geological Timescale: NZGT2015/1. GNS Science Report 2012(39) 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

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 127731 collections

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International Chronostratigraphic TimescaleOrdovician of the BalticSilurian of North AmericaObsolete Carboniferous Ages of ChinaPermian-Jurassic of New ZealandDevonian of CzechoslovakiaAmmonite Chrons of Northwest EuropePermian of Western EuropeCambrian of North AmericaCarboniferous of North AmericaDevonian of Germany
JurassicLate JurassicTithonianOtekePuaroan145
Kimmeridgian149.2
KawhiaOhauan150
Heterian154.5
Oxfordian154.8
Middle JurassicCallovian161.5
Temaikan164.3
Bathonian165.3
BajocianParkinsoni/Garantiana/Subfurcatum/Sauzei/Laeviuscula/Discites168.2
Humphresianum168.4
AalenianConcavum/Murchisonae/Opalinum170.9
Early JurassicToarcianLevesquei/Variabilis/BifronsThouarsense174.7
HerangiUruroan176
180.1
Serpentinum/Falciferum/Tenuicostatum182
PliensbachianSpinatum/Margaritatus/Davoei/Ibex/Jamesoni184.2
Aratauran188.9
SinemurianRaricostatum/Oxynotum/Obtusum/Turneri/Semicostatum/Bucklandi192.9
HettangianAngulata/Liasicus/Planorbis199.5
TriassicLate TriassicRhaetianBalfourOtapirian201.4
NorianWarepan208.5
Otamitan217
Oretian221
Carnian227
GoreKaihikuan227.5
Middle TriassicLadinian237
Etalian238
Anisian242
Malakovian246
Early TriassicOlenekian247.2
Nelsonian249
Induan251.2
DUrvilleMakarewan251.5
PermianLopingianChanghsingian251.902
Waiitian253.2
WuchiapingianZechstein254.14
Puruhauan254.2
GuadalupianCapitanianAparimaFlettianRotliegendes259.51
Wordian264.28
Barettian266
Roadian266.9
CisuralianKungurian273.01
Mangapirian276
ArtinskianAutunian283.5
Telfordian285
288.5
Sakmarian290.1
AsselianBursumian †293.52
CarboniferousPennsylvanianGzhelianMapingian †Virgilian298.9
KasimovianMissourian303.7
Desmoinesian305.9 *
Moscovian307
Atokan312.7 *
Bashkirian315.2
Morrowan318.4 *
MississippianSerpukhovianChesterian323.2
Visean330.9
Meramecian335.8 *
Osagean343.1 *
Tournaisian346.7
Kinderhookian351.9 *
DevonianLate DevonianFamennianWocklum/Dasberg/Hemberg/Nehden358.9
FrasnianAdorf372.2
Middle DevonianGivetianSrbskoGivetian382.7
EifelianChotecEifelian387.7
Early DevonianEmsianDaleje/ZlichovianEmsian393.3
PragianPragianSiegen407.6
LochkovianLochkovianGedinnine410.8
SilurianPridoliCayugan419.2
Niagaran422.5 *
LudlowLudfordian423
Gorstian425.6
WenlockHomerianLockportian427.4
Sheinwoodian430.5
LlandoveryTelychianOntarian433.4
Aeronian438.5
Alexandrian438.7 *
MedinanClinton440.1 *
440.7 *
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianHarjuPorkuni443.8
KatianPirgu445.2
Vormsi449.6 *
NabalaJohvi †450 *
ViruRakvere450.6 *
Oandu452 *
SandbianKeilaIdavere †453
Haljala453.9
Kukruse456.4 *
UhakuAluoja †457.5 *
Middle OrdovicianDarriwilian458.4
Lasnamagi458.9 *
Aseri460.4 *
OelandKunda462.9 *
Valaste †/Hunderum464.3 *
VolkhovLangevoja †/Vaana/Saka467.1 *
Dapingian467.3
Billingen469.3 *
Early OrdovicianFloian470
Latorp †470.1 *
Hunneberg473.7 *
Tremadocian477.7
Varangu481.3 *
Pakerort482.2 *
CambrianFurongianStage 10Franconian †/Dresbachian/Millardan485.4
486.3 *
486.5
Sunwaptan487.5
Jiangshanian489.5
Steptoean493 *
Paibian494
MiaolingianGuzhangianMarjumianAlbertian †497
Drumian500.5
WuliuanTopazan504.5
Delamaran506.5
Series 2Stage 4Waucoban †509
Dyeran511 *
Stage 3514
Montezuman514.8 *
Begadean519.9 *
TerreneuvianStage 2521
Fortunian529
538.8