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
  • 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
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • A. D. Barnosky, M. Holmes, R. Kirchholtes, E. Lindsey, K.C. Maguire, A.W. Poust, M.A. Stegner, J. Sunseri, B. Swartz, J. Swift, N.A. Villavicencio and G. Wogan. 2014. Prelude to the Anthropocene: Two new North American Land Mammal Ages (NALMAs). The Anthropocene Review I(3):225-242 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.

This timescale is used in the definition of 126699 collections

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International Chronostratigraphic TimescaleCenozoic SubepochsNorth American Land Mammal AgesPaleogene Mammal Ages of Asia
18.5
PaleogeneOligoceneChattianLate OligoceneArikareeanTabenbulakianHsandagolian23.03
RupelianEarly OligoceneKekeamuan27.82
Whitneyan29.5
Orellan31.8
EocenePriabonianLate EoceneChadronianHouldjinian/Ergilian/Ulangochuian33.9
Duchesnean37
BartonianMiddle EoceneSharamurunian/Irdinmanhan/Arshantan37.71
Uintan39.7
Lutetian41.2
Bridgerian46.2
YpresianEarly EoceneBumbanian47.8
Wasatchian50.5
Clarkforkian54.9
PaleoceneThanetianLate PaleoceneGashatan56
Tiffanian56.2
SelandianMiddle Paleocene59.2
Torrejonian60.9
DanianEarly Paleocene61.6
Puercan63.8
66