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
  • 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
  • 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
  • M. Freudenthal. 2006. Mammal Paleogene zones. personal communication 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 TimescaleCenozoic SubepochsNorth American Mammal Subages/ZonesMammal Paleogene Zones
18.5
PaleogeneOligoceneChattianLate Oligocenelate Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonianMP 30/MP 29/MP 28/MP 27/MP 26MP 2523.03
Monroecreekian23.1 *
Geringian24.7 *
RupelianEarly OligoceneMP 24/MP 23/MP 22/MP 2127.82
29.5
EocenePriabonianLate EoceneLate Chadronian/Middle Chadronian/Early ChadronianMP 20/MP 19/MP 18/MP 17B/MP 17A33.9
37
BartonianMiddle EoceneMP 1637.71
Late Uintan/Early Uintan39.7
LutetianMP 15/MP 14/MP 13/MP 12/MP 1141.2
Twinbuttean/Blacksforkian/Gardnerbuttian46.2
YpresianEarly EoceneMP 10/MP 8 + 9/MP 747.8
Lostcabinian/Lysitean/Graybullian/Sandcouleean50.5
Cf3/Cf2/Cf154.9
PaleoceneThanetianLate PaleoceneMP 6MP 1 - 556
Ti6/Ti5/Ti4/Ti3/Ti2/Ti156.2
SelandianMiddle Paleocene59.2
To3/To2/To160.9
DanianEarly Paleocene61.6
Pu3/Pu2/Pu163.8
66