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, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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
  • 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
  • Z.-X. Qiu and Z.-D. Qiu. 1995. Chronological sequence and subdivision of Chinese Neogene mammalian faunas. Palaeogeography, Palaeoclimatology, Palaeoecology 116(1-2):41-70 view
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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 126585 collections

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International Chronostratigraphic TimescaleNorth American Land Mammal AgesCenozoic Subepochs
18.5
PaleogeneOligoceneChattianArikareeanLate Oligocene23.03
RupelianEarly Oligocene27.82
Whitneyan29.5
Orellan31.8
EocenePriabonianChadronianLate Eocene33.9
Duchesnean37
BartonianMiddle Eocene37.71
Uintan39.7
Lutetian41.2
Bridgerian46.2
YpresianEarly Eocene47.8
Wasatchian50.5
Clarkforkian54.9
PaleoceneThanetianLate Paleocene56
Tiffanian56.2
SelandianMiddle Paleocene59.2
Torrejonian60.9
DanianEarly Paleocene61.6
Puercan63.8
66