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. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • J. Meng and M. C. McKenna. 1998. Faunal turnovers of Paleogene mammals from the Mongolian Plateau. Nature 394:364-367 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

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 126133 collections

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International Chronostratigraphic TimescaleTen Million Year BinsCambrian of KazakhstanPaleogene Mammal Ages of AsiaCambrian of West AvaloniaNorth American Mammal Subages/ZonesPermian of the Salt RangeOrdovician of Ibero-BohemiaObsolete Names for ICS Units
QuaternaryHoloceneMeghalayanCenozoic 60
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate PleistoceneSheridanian0.0117
Chibanian0.129
Cudahyan/Sappan0.21
Calabrian0.774
Senecan/Rexroadian1.4
Gelasian1.8
NeogenePliocenePiacenzianTertiary †2.58
Zanclean3.6
Late Hemphillian/late Early Hemphillian/early Early Hemphillian4.7
MioceneMessinian5.333
Tortonian7.246
Late Clarendonian/Early Clarendonian9.4
SerravallianCenozoic 511.63
late Late Barstovian/early Late Barstovian/Early Barstovian12.5
Langhian13.82
Burdigalian15.98
Late Hemingfordian/Early Hemingfordian16.3
late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonian18.5
Aquitanian20.44
PaleogeneOligoceneChattianCenozoic 4TabenbulakianHsandagolian23.03
Monroecreekian23.1 *
Geringian24.7 *
RupelianKekeamuan27.82
29.5
EocenePriabonianCenozoic 3Houldjinian/Ergilian/UlangochuianLate Chadronian/Middle Chadronian/Early Chadronian33.9
37
BartonianSharamurunian/Irdinmanhan/Arshantan37.71
Late Uintan/Early Uintan39.7
LutetianCenozoic 241.2
Twinbuttean/Blacksforkian/Gardnerbuttian46.2
YpresianBumbanian47.8
Lostcabinian/Lysitean/Graybullian/Sandcouleean50.5
Cf3/Cf2/Cf154.9
PaleoceneThanetianCenozoic 1Gashatan56
Ti6/Ti5/Ti4/Ti3/Ti2/Ti156.2
Selandian59.2
To3/To2/To160.9
Danian61.6
Pu3/Pu2/Pu163.8
CretaceousLate CretaceousMaastrichtianCretaceous 866
CampanianCretaceous 772.1
SantonianCretaceous 683.6
Coniacian86.3
Turonian89.8
CenomanianCretaceous 593.9
Early CretaceousAlbianCretaceous 4100.5
AptianCretaceous 3113
BarremianCretaceous 2121.4
Hauterivian125.77
ValanginianCretaceous 1132.6
Berriasian139.8
JurassicLate JurassicTithonianJurassic 6145
KimmeridgianJurassic 5149.2
Oxfordian154.8
Middle JurassicCallovian161.5
BathonianJurassic 4165.3
Bajocian168.2
AalenianJurassic 3170.9
Early JurassicToarcian174.7
PliensbachianJurassic 2184.2
SinemurianJurassic 1192.9
Hettangian199.5
TriassicLate TriassicRhaetianTriassic 4201.4
Norian208.5
CarnianTriassic 3227
Middle TriassicLadinianTriassic 2237
Anisian242
Early TriassicOlenekianTriassic 1247.2
Induan251.2
Kathwai251.5 *
PermianLopingianChanghsingianPermian 4251.902
252.4 *
Chhidru252.9 *
WuchiapingianLongtanian †254.14
Kalabagh255 *
Wargal256 *
GuadalupianCapitanian259.51
Wordian264.28
265.3 *
Amb266.1 *
RoadianPermian 3266.9
270.7 *
CisuralianKungurianPermian 2273.01
Artinskian283.5
Sakmarian290.1
AsselianPermian 1293.52
CarboniferousPennsylvanianGzhelianCarboniferous 5298.9
Kasimovian303.7
MoscovianCarboniferous 4307
Bashkirian315.2
MississippianSerpukhovianCarboniferous 3323.2
ViseanCarboniferous 2330.9
TournaisianCarboniferous 1346.7
DevonianLate DevonianFamennianDevonian 5358.9
FrasnianDevonian 4372.2
Middle DevonianGivetianDevonian 3382.7
Eifelian387.7
Early DevonianEmsianDevonian 2393.3
PragianDevonian 1407.6
Lochkovian410.8
SilurianPridoliSilurian 2419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychianSilurian 1433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianOrdovician 5Kosovian443.8
KatianKralodvorianBohdalec †445.2
Berounian449.7 *
SandbianOrdovician 4453
Zahorany †/ViniceLetna †456.2 *
Liben †458 *
Middle OrdovicianDarriwilianOrdovician 3458.4
Dobrotivian458.5 *
Oretanian459.7 *
Sarka †461.7 *
DapingianOrdovician 2Klabava †467.3
Arenigian468
Early OrdovicianFloian470
TremadocianOrdovician 1UngurianTremadocian477.7
CambrianFurongianStage 10Cambrian 5Batyrbaian485.4
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Paibian494
MiaolingianGuzhangianCambrian 4AyusokkanianSeries 3 †497
Arcadian498.4
499.5
DrumianZhanaarykian500.5
Tuesaian503
WuliuanCambrian 3Stage 5 †504.5
505.3
Series 2Stage 4Branchian509
Toyonian510 *
Botomian512.5 *
Stage 3Cambrian 2514
Atdabanian515.6 *
Placentian517.1
TerreneuvianStage 2Tommotian521
525.5
FortunianCambrian 1529
538.8