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, F. P. Agterberg, J. G. Ogg, J. Hardenbol, P. Van Veen, J. Thierry, and Z. Huang. 1995. A Triassic, Jurassic, and Cretaceous time scale. SEPM Special Publication 54 view
  • F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • J. Palfy, P. L. Smith, and J. K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time scale for the Jurassic. Canadian Journal of Earth Sciences 37(6):923-944 view
  • F. F. Steininger, W. A. Berggren, D. V. Kent, R. L. Bernor, S. Sen and J. Agusti. 1996. Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units. The Evolution of Western Eurasian Neogene Mammal Faunas (eds. R. L. Bernor, V. Fahlbusch, and H.-W. Mittmann) view
  • Z.-X. Qiu and Z.-D. Qiu. 1995. Chronological sequence and subdivision of Chinese Neogene mammalian faunas. Palaeogeography, Palaeoclimatology, Palaeoecology 116(1-2):41-70 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
  • P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 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

Show more time

Show linear time

International Chronostratigraphic TimescaleMesozoic SubagesTen Million Year BinsEuropean Faunal UnitsNeogene Mammal Ages of ChinaOrdovician of AustraliaPermian of the Salt RangeSilurian of North AmericaCenozoic Subepochs of Southern EuropeObsolete Names for ICS Units
QuaternaryHoloceneMeghalayanCenozoic 60
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate PleistoceneNihewanianTarantian0.0117
ChibanianIonian0.129
Calabrian0.774
Gelasian1.8
NeogenePliocenePiacenzianVillanyianYusheanTertiary †2.58
Ruscinian3.1 *
Zanclean3.6
Baodean4.9
MioceneMessinianTurolian5.333
Tortonian7.246
Vallesian8.7
Tunggurian11.1
SerravallianCenozoic 5Astaracian11.63
LanghianShanwangian13.82
BurdigalianOrleanian15.98
Xiejiaan16.9
Agenian20
Aquitanian20.44
PaleogeneOligoceneChattianCenozoic 423.03
Rupelian27.82
EocenePriabonianCenozoic 333.9
Bartonian37.71
LutetianCenozoic 241.2
Ypresian47.8
PaleoceneThanetianCenozoic 156
Selandian59.2
Danian61.6
CretaceousLate CretaceousMaastrichtianLate Maastrichtian/Early MaastrichtianCretaceous 866
CampanianLate Campanian/Middle Campanian/Early CampanianCretaceous 772.1
SantonianLate Santonian/Middle Santonian/Early SantonianCretaceous 683.6
ConiacianLate Coniacian/Middle Coniacian/Early Coniacian86.3
TuronianLate Turonian/Middle Turonian/Early Turonian89.8
CenomanianLate Cenomanian/Middle Cenomanian/Early CenomanianCretaceous 593.9
Early CretaceousAlbianLate AlbianCretaceous 4100.5
Middle Albian106.2 *
Early Albian109.9 *
AptianLate AptianCretaceous 3113
Early Aptian119.5 *
BarremianLate Barremian/Early BarremianCretaceous 2121.4
HauterivianLate Hauterivian/Early Hauterivian125.77
ValanginianLate Valanginian/Early ValanginianCretaceous 1132.6
BerriasianLate Berriasian139.8
Middle Berriasian140.6 *
Early Berriasian142.7 *
JurassicLate JurassicTithonianLate TithonianMiddle TithonianJurassic 6145
Early Tithonian146.3 *
KimmeridgianLate KimmeridgianJurassic 5149.2
Early Kimmeridgian152.2 *
OxfordianLate OxfordianMiddle Oxfordian/Early Oxfordian154.8
157.9 *
Middle JurassicCallovianLate Callovian/Middle Callovian/Early Callovian161.5
BathonianLate Bathonian/Middle Bathonian/Early BathonianJurassic 4165.3
BajocianLate Bajocian168.2
Early Bajocian168.6 *
AalenianLate Aalenian/Middle Aalenian/Early AalenianJurassic 3170.9
Early JurassicToarcianLate Toarcian174.7
Middle Toarcian180.4 *
Early Toarcian182.9 *
PliensbachianLate Pliensbachian/Early PliensbachianJurassic 2184.2
SinemurianLate Sinemurian/Early SinemurianJurassic 1192.9
HettangianLate Hettangian/Middle Hettangian/Early Hettangian199.5
TriassicLate TriassicRhaetianTriassic 4201.4
NorianSevatian208.5
Alaunian213.2 *
Lacian216.7 *
CarnianTuvalianTriassic 3227
Julian233.4 *
Middle TriassicLadinianLongobardianTriassic 2237
Fassanian239.7 *
AnisianIllyrian242
Pelsonian243.8 *
Bithynian244.7 *
Aegean245.5 *
Early TriassicOlenekianSpathianTriassic 1247.2
Smithian248.9 *
InduanDienerian251.2
Griesbachian251.4 *
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 2Cayugan419.2
Niagaran422.5 *
LudlowLudfordian423
Gorstian425.6
WenlockHomerianLockportian427.4
Sheinwoodian430.5
LlandoveryTelychianSilurian 1Ontarian433.4
Aeronian438.5
Alexandrian438.7 *
MedinanClinton440.1 *
440.7 *
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianOrdovician 5Bolindian443.8
Katian445.2
Eastonian449 *
Gisbornian452 *
SandbianOrdovician 4453
Middle OrdovicianDarriwilianOrdovician 3Darriwilian458.4
DapingianOrdovician 2Yapeenian467.3
Castlemainian468.5 *
Early OrdovicianFloianChewtonian470
Bendigonian471.8 *
Lancefieldian473.5 *
TremadocianOrdovician 1477.7
Warendian482.8 *
CambrianFurongianStage 10Cambrian 5485.4
Jiangshanian489.5
Paibian494
MiaolingianGuzhangianCambrian 4Series 3 †497
Drumian500.5
WuliuanCambrian 3Stage 5 †504.5
Series 2Stage 4509
Stage 3Cambrian 2514
TerreneuvianStage 2521
FortunianCambrian 1529
538.8