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. J. Prevosti, C. O. Romano, A. M. Forasiepi, S. Hemming, R. Bonini, A. M. Candela, E. Cerdeño, M. C. Madozzo Jaén, P. E. Ortiz, F. Pujos, L. Rasia, G. I. Schmidt, M. Taglioretti, R. D. E. MacPhee, and U. F. J. Pardiñas. 2021. New radiometric 40Ar–39Ar dates and faunistic analyses refine evolutionary dynamics of Neogene vertebrate assemblages in southern South America. Scientific Reports 2021(11):9830 view
  • J. J. Flynn and C. C. Swisher, III. 1995. Cenozoic South American Land Mammal Ages: correlation to global geochronology. Geochronology Time Scales and Global Stratigraphic Correlation, SEPM Special Publication 54:317-333 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, 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
  • 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.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 126536 collections

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International Chronostratigraphic TimescaleSouth American Land Mammal AgesMammal Paleogene ZonesCenozoic Subepochs
20.9
PaleogeneOligoceneChattianDeseadanMP 30/MP 29/MP 28/MP 27/MP 26MP 25Late Oligocene23.03 *
RupelianMP 24/MP 23/MP 22/MP 21Early Oligocene27.82
Tinguirirican28.9 *
EocenePriabonianMP 20/MP 19/MP 18/MP 17B/MP 17ALate Eocene33.9
Divisaderan35.9 *
BartonianMP 16Middle Eocene37.71
LutetianMP 15/MP 14/MP 13/MP 12/MP 1141.2
Mustersan41.9 *
YpresianMP 10/MP 8 + 9/MP 7Early Eocene47.8
Casamayoran47.9 *
PaleoceneThanetianRiochicanMP 6MP 1 - 5Late Paleocene56
Itaboraian56.9 *
Peligran58.9 *
SelandianMiddle Paleocene59.2
DanianEarly Paleocene61.6
Tiupampan62.4 *
66