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, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • D. H. Erwin and S. A. Bowring. 2004. Cambrian time scale. view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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.

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

This timescale is used in the definition of 126884 collections

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International Chronostratigraphic TimescaleObsolete Names for ICS UnitsPermian of ChinaCambrian of SiberiaTen Million Year BinsCambrian of West AvaloniaCambrian of KazakhstanSilurian of the BalticCarbo-Permian of the Russian PlatformNorth American Mammal Subages/ZonesMammal Paleogene Zones
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 4MP 30/MP 29/MP 28/MP 27/MP 26MP 2523.03
Monroecreekian23.1 *
Geringian24.7 *
RupelianMP 24/MP 23/MP 22/MP 2127.82
29.5
EocenePriabonianCenozoic 3Late Chadronian/Middle Chadronian/Early ChadronianMP 20/MP 19/MP 18/MP 17B/MP 17A33.9
37
BartonianMP 1637.71
Late Uintan/Early Uintan39.7
LutetianCenozoic 2MP 15/MP 14/MP 13/MP 12/MP 1141.2
Twinbuttean/Blacksforkian/Gardnerbuttian46.2
YpresianMP 10/MP 8 + 9/MP 747.8
Lostcabinian/Lysitean/Graybullian/Sandcouleean50.5
Cf3/Cf2/Cf154.9
PaleoceneThanetianCenozoic 1MP 6MP 1 - 556
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
PermianLopingianChanghsingianMeishanianPermian 4Melekhovian251.902
Baoqingian253.4 *
WuchiapingianLongtanian †Laoshanian254.14
Laibinian257.7 *
GuadalupianCapitanianLengwuan259.51
WordianKuhfengian264.28
Noginskian264.9 *
RoadianPermian 3266.9
CisuralianKungurianLuodianianPermian 2273.01
Pavlovoposadian276.8 *
Artinskian283.5
Longlinian285.4 *
Rusavkinian287.6 *
Sakmarian290.1
AsselianZisongianPermian 1293.52
CarboniferousPennsylvanianGzhelianCarboniferous 5298.9
300.1
KasimovianDorogomilovian303.7
Khamovnikian304.8
Krevyakinian305.8 *
MoscovianCarboniferous 4Myachkovian307
Podolskian308.9 *
Kashirian311.4 *
Vereian313.8
Melekessian314.8
Bashkirian315.2
Cheremshanian316.9 *
Prikamian318.6 *
Severokeltmian319.9 *
Krasnopolyanian321.2 *
Voznesenian321.9 *
MississippianSerpukhovianCarboniferous 3Zapaltjubian323.2
Protvian324.4 *
Steshevian326.8 *
Tarusian329 *
ViseanCarboniferous 2Venevian330.9
Mikhailovian331.9 *
Aleksinian333.7 *
Tulian335.8 *
Bobrikian339.9 *
Radaevkian343.4 *
TournaisianCarboniferous 1Kosvian346.7
Kizelian350.7 *
Cherepetian351.9 *
Karakubian354.4 *
Upinian356.3 *
Malevkian357.6 *
Gumerovian358 *
DevonianLate DevonianFamennianDevonian 5358.9
FrasnianDevonian 4372.2
Middle DevonianGivetianDevonian 3382.7
Eifelian387.7
Early DevonianEmsianDevonian 2393.3
PragianDevonian 1407.6
Lochkovian410.8
SilurianPridoliSilurian 2Ohesaare419.2
Kaugetuma421.7 *
LudlowLudfordianKuressaare423
Paadla423.4 *
Gorstian425.6
WenlockHomerianRootsikula427.4
Jaagarahu429.2 *
Sheinwoodian430.5
Jaani431.8 *
LlandoveryTelychianSilurian 1433.4
Adavere434 *
Aeronian438.5
Raikkula439.4 *
Rhuddanian440.8
Juuru441.4 *
OrdovicianLate OrdovicianHirnantianOrdovician 5443.8
Katian445.2
SandbianOrdovician 4453
Middle OrdovicianDarriwilianOrdovician 3458.4
DapingianOrdovician 2467.3
Early OrdovicianFloian470
TremadocianOrdovician 1Ungurian477.7
Mansian †483.55 *
CambrianFurongianStage 10BatyrbaianTavgian †Ketyan †/YurakianCambrian 5Batyrbaian485.4
Jiangshanian489.5
AksaianAksaian490.7 *
SakianSakian492.2 *
Paibian494
Ensyan †/Maduan/Nganasanian494.7 *
MiaolingianGuzhangianSeries 3 †AyusokkanianCambrian 4Ayusokkanian497
Arcadian498.4
Mayan/Menevian499.5
DrumianZhanaarykian500.5
Tuesaian503
WuliuanStage 5 †Amgan/SolvanCambrian 3504.5
505.3
Series 2Stage 4Branchian509
ToyonianLenian †Toyonian510 *
BotomianBotomian512.5 *
Stage 3Cambrian 2514
AtdabanianAtdabanian515.6 *
Placentian517.1
TerreneuvianStage 2TommotianTommotian521
Nemakit-Daldynian525.5
FortunianManykaian †Cambrian 1529
538.8