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
  • 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
  • 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
  • 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. 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
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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
  • J. I. Raine, A. G. Beu, A. F. Boyes, H. J. Campbell, R. A. Cooper, J. S. Crampton, M. P. Crundwell, C. J. Hollis, and H. E. G. Morgans. 2015. Revised Calibration of the New Zealand Geological Timescale: NZGT2015/1. GNS Science Report 2012(39) view
  • J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 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 126610 collections

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International Chronostratigraphic TimescaleNorth American Land Mammal AgesSouth American Land Mammal AgesNorth American Mammal Subages/ZonesPaleogene Mammal Ages of Asia
18.5
20.9
PaleogeneOligoceneChattianArikareeanDeseadanlate Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonianTabenbulakianHsandagolian23.03 *
Monroecreekian23.1 *
Geringian24.7 *
RupelianKekeamuan27.82
Tinguirirican28.9 *
Whitneyan29.5
Orellan31.8
EocenePriabonianChadronianLate Chadronian/Middle Chadronian/Early ChadronianHouldjinian/Ergilian/Ulangochuian33.9
Divisaderan35.9 *
Duchesnean37
BartonianSharamurunian/Irdinmanhan/Arshantan37.71
UintanLate Uintan/Early Uintan39.7
Lutetian41.2
Mustersan41.9 *
BridgerianTwinbuttean/Blacksforkian/Gardnerbuttian46.2
YpresianBumbanian47.8
Casamayoran47.9 *
WasatchianLostcabinian/Lysitean/Graybullian/Sandcouleean50.5
ClarkforkianCf3/Cf2/Cf154.9
PaleoceneThanetianRiochicanGashatan56
TiffanianTi6/Ti5/Ti4/Ti3/Ti2/Ti156.2
Itaboraian56.9 *
Peligran58.9 *
Selandian59.2
TorrejonianTo3/To2/To160.9
Danian61.6
Tiupampan62.4 *
PuercanPu3/Pu2/Pu163.8
66