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
  • P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 view
  • M. Freudenthal. 2006. Mammal Paleogene zones. personal communication 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.

This timescale is used in the definition of 125945 collections

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International Chronostratigraphic TimescaleTen Million Year BinsMammal Paleogene ZonesCenozoic Subepochs
PaleogeneOligoceneChattianCenozoic 4MP 30/MP 29/MP 28/MP 27/MP 26MP 25Late Oligocene23.03
RupelianMP 24/MP 23/MP 22/MP 21Early Oligocene27.82
EocenePriabonianCenozoic 3MP 20/MP 19/MP 18/MP 17B/MP 17ALate Eocene33.9
BartonianMP 16Middle Eocene37.71
LutetianCenozoic 2MP 15/MP 14/MP 13/MP 12/MP 1141.2
YpresianMP 10/MP 8 + 9/MP 7Early Eocene47.8
PaleoceneThanetianCenozoic 1MP 6MP 1 - 5Late Paleocene56
SelandianMiddle Paleocene59.2
DanianEarly Paleocene61.6
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