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
  • 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
  • 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
  • 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 126734 collections

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International Chronostratigraphic TimescaleTen Million Year BinsAmmonite Chrons of Northwest EuropeAmmonite Chrons of North America
JurassicLate JurassicTithonianJurassic 6145
KimmeridgianJurassic 5149.2
Oxfordian154.8
Middle JurassicCallovian161.5
BathonianJurassic 4165.3
BajocianParkinsoni/Garantiana/Subfurcatum/Sauzei/Laeviuscula/DiscitesEpizigzagiceras168.2
HumphresianumRotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense168.4
AalenianJurassic 3Concavum/Murchisonae/OpalinumHowelli/Scissum/Westermanni170.9
Early JurassicToarcianLevesquei/Variabilis/BifronsThouarsenseYakounensis/Hillebrandti/Crassicosta174.7
Planulata179.3 *
Arnioceras arnouldi179.8 *
180.1
Kanense181.3 *
Serpentinum/Falciferum/Tenuicostatum182
Carlottense182.3 *
Kunae183.5 *
PliensbachianJurassic 2Spinatum/Margaritatus/Davoei/Ibex/Jamesoni184.2
Freboldi185.1 *
Whiteavesi/ImlayiTetraspidoceras186.2 *
189.2 *
Plesechioceras harbledownense/Asteroceras varians/CoronicerasCanadensis190.3 *
SinemurianJurassic 1Raricostatum/Oxynotum/Obtusum/Turneri/Semicostatum/Bucklandi192.9
PseudaetomocerasPsiloceras196.4 *
Franziceras/Euphyllites196.5 *
HettangianAngulata/Liasicus/Planorbis199.5
201.4