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
  • M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
  • J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 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
  • J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 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
  • F. M. Gradstein, F. P. Agterberg, J. G. Ogg, J. Hardenbol, P. Van Veen, J. Thierry, and Z. Huang. 1995. A Triassic, Jurassic, and Cretaceous time scale. SEPM Special Publication 54 view
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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
  • J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 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 126654 collections

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International Chronostratigraphic TimescaleNorth American Mammal Subages/ZonesObsolete Names for ICS UnitsCretaceous-Cenozoic of New ZealandPaleogene Mammal Ages of Asia
2.58
18.5
21.7
PaleogeneOligoceneChattianlate Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonianTertiary †LandonWaitakianTabenbulakianHsandagolian23.03
Monroecreekian23.1 *
Geringian24.7 *
Duntroonian25.2
Whaingaroan27.3
RupelianKekeamuan27.82
29.5
EocenePriabonianLate Chadronian/Middle Chadronian/Early ChadronianHouldjinian/Ergilian/Ulangochuian33.9
ArnoldRunangan34.6
Kaiatan36.7
37
BartonianSharamurunian/Irdinmanhan/Arshantan37.71
Bortonian39.1
Late Uintan/Early Uintan39.7
Lutetian41.2
DannevirkePorangan42.6
Heretaungan45.7
Twinbuttean/Blacksforkian/Gardnerbuttian46.2
YpresianBumbanian47.8
Mangaorapan48.9
Lostcabinian/Lysitean/Graybullian/Sandcouleean50.5
Waipawan52
Cf3/Cf2/Cf154.9
PaleoceneThanetianTeurianGashatan56
Ti6/Ti5/Ti4/Ti3/Ti2/Ti156.2
Selandian59.2
To3/To2/To160.9
Danian61.6
Pu3/Pu2/Pu163.8
66