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
  • 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
  • M. Harzhauser and W. E. Piller. 2004. Integrated stratigraphy of the Sarmatian (Upper Middle Miocene) in the western Central Paratethys. Stratigraphy 1(1):65-86 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

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 127403 collections

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International Chronostratigraphic TimescaleNorth American Mammal Subages/ZonesMammal Paleogene ZonesTen Million Year BinsNorth American Land Mammal Ages
18.5
PaleogeneOligoceneChattianlate Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonianMP 30/MP 29/MP 28/MP 27/MP 26MP 25Cenozoic 4Arikareean23.03
Monroecreekian23.1 *
Geringian24.7 *
RupelianMP 24/MP 23/MP 22/MP 2127.82
Whitneyan29.5
Orellan31.8
EocenePriabonianLate Chadronian/Middle Chadronian/Early ChadronianMP 20/MP 19/MP 18/MP 17B/MP 17ACenozoic 3Chadronian33.9
Duchesnean37
BartonianMP 1637.71
Late Uintan/Early UintanUintan39.7
LutetianMP 15/MP 14/MP 13/MP 12/MP 11Cenozoic 241.2
Twinbuttean/Blacksforkian/GardnerbuttianBridgerian46.2
YpresianMP 10/MP 8 + 9/MP 747.8
Lostcabinian/Lysitean/Graybullian/SandcouleeanWasatchian50.5
Cf3/Cf2/Cf1Clarkforkian54.9
PaleoceneThanetianMP 6MP 1 - 5Cenozoic 156
Ti6/Ti5/Ti4/Ti3/Ti2/Ti1Tiffanian56.2
Selandian59.2
To3/To2/To1Torrejonian60.9
Danian61.6
Pu3/Pu2/Pu1Puercan63.8
66