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
  • 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
  • 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
  • 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
  • M. Freudenthal. 2006. Mammal Paleogene zones. personal communication 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

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 126662 collections

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International Chronostratigraphic TimescaleDevonian SubagesMesozoic SubagesCambrian of KazakhstanOrdovician of Ibero-BohemiaSilurian of the BalticMammal Paleogene ZonesNorth American Land Mammal AgesObsolete Names for ICS Units
QuaternaryHoloceneMeghalayanSaintaugustinean0
Santarosean0.0004
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate Pleistocene0.0117
Rancholabrean0.014
Chibanian0.129
Irvingtonian0.21
Calabrian0.774
Blancan1.4
Gelasian1.8
NeogenePliocenePiacenzianTertiary †2.58
Zanclean3.6
Hemphillian4.7
MioceneMessinian5.333
Tortonian7.246
Clarendonian9.4
Serravallian11.63
Barstovian12.5
Langhian13.82
Burdigalian15.98
Hemingfordian16.3
Arikareean18.5
Aquitanian20.44
PaleogeneOligoceneChattianMP 30/MP 29/MP 28/MP 27/MP 26MP 2523.03
RupelianMP 24/MP 23/MP 22/MP 2127.82
Whitneyan29.5
Orellan31.8
EocenePriabonianMP 20/MP 19/MP 18/MP 17B/MP 17AChadronian33.9
Duchesnean37
BartonianMP 1637.71
Uintan39.7
LutetianMP 15/MP 14/MP 13/MP 12/MP 1141.2
Bridgerian46.2
YpresianMP 10/MP 8 + 9/MP 747.8
Wasatchian50.5
Clarkforkian54.9
PaleoceneThanetianMP 6MP 1 - 556
Tiffanian56.2
Selandian59.2
Torrejonian60.9
Danian61.6
Puercan63.8
CretaceousLate CretaceousMaastrichtianLate Maastrichtian/Early Maastrichtian66
CampanianLate Campanian/Middle Campanian/Early Campanian72.1
SantonianLate Santonian/Middle Santonian/Early Santonian83.6
ConiacianLate Coniacian/Middle Coniacian/Early Coniacian86.3
TuronianLate Turonian/Middle Turonian/Early Turonian89.8
CenomanianLate Cenomanian/Middle Cenomanian/Early Cenomanian93.9
Early CretaceousAlbianLate Albian100.5
Middle Albian106.2 *
Early Albian109.9 *
AptianLate Aptian113
Early Aptian119.5 *
BarremianLate Barremian/Early Barremian121.4
HauterivianLate Hauterivian/Early Hauterivian125.77
ValanginianLate Valanginian/Early Valanginian132.6
BerriasianLate Berriasian139.8
Middle Berriasian140.6 *
Early Berriasian142.7 *
JurassicLate JurassicTithonianLate TithonianMiddle Tithonian145
Early Tithonian146.3 *
KimmeridgianLate Kimmeridgian149.2
Early Kimmeridgian152.2 *
OxfordianLate OxfordianMiddle Oxfordian/Early Oxfordian154.8
157.9 *
Middle JurassicCallovianLate Callovian/Middle Callovian/Early Callovian161.5
BathonianLate Bathonian/Middle Bathonian/Early Bathonian165.3
BajocianLate Bajocian168.2
Early Bajocian168.6 *
AalenianLate Aalenian/Middle Aalenian/Early Aalenian170.9
Early JurassicToarcianLate Toarcian174.7
Middle Toarcian180.4 *
Early Toarcian182.9 *
PliensbachianLate Pliensbachian/Early Pliensbachian184.2
SinemurianLate Sinemurian/Early Sinemurian192.9
HettangianLate Hettangian/Middle Hettangian/Early Hettangian199.5
TriassicLate TriassicRhaetian201.4
NorianSevatian208.5
Alaunian213.2 *
Lacian216.7 *
CarnianTuvalian227
Julian233.4 *
Middle TriassicLadinianLongobardian237
Fassanian239.7 *
AnisianIllyrian242
Pelsonian243.8 *
Bithynian244.7 *
Aegean245.5 *
Early TriassicOlenekianSpathian247.2
Smithian248.9 *
InduanDienerian251.2
Griesbachian251.4 *
PermianLopingianChanghsingian251.902
WuchiapingianLongtanian †254.14
GuadalupianCapitanian259.51
Wordian264.28
Roadian266.9
CisuralianKungurian273.01
Artinskian283.5
Sakmarian290.1
Asselian293.52
CarboniferousPennsylvanianGzhelian298.9
Kasimovian303.7
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennianLate Famennian358.9
Middle Famennian365.3 *
Early Famennian368.5 *
FrasnianLate Frasnian372.2
Middle Frasnian375.4 *
Early Frasnian379.3 *
Middle DevonianGivetianLate Givetian382.7
Middle Givetian383.7 *
Early Givetian385.9 *
EifelianLate Eifelian387.7
Early Eifelian390.3 *
Early DevonianEmsianLate Emsian393.3
Early Emsian398.3 *
PragianPragian407.6
LochkovianLate Lochkovian410.8
Middle Lochkovian412.8 *
Early Lochkovian415.6 *
SilurianPridoliOhesaare419.2
Kaugetuma421.7 *
LudlowLudfordianKuressaare423
Paadla423.4 *
Gorstian425.6
WenlockHomerianRootsikula427.4
Jaagarahu429.2 *
Sheinwoodian430.5
Jaani431.8 *
LlandoveryTelychian433.4
Adavere434 *
Aeronian438.5
Raikkula439.4 *
Rhuddanian440.8
Juuru441.4 *
OrdovicianLate OrdovicianHirnantianKosovian443.8
KatianKralodvorianBohdalec †445.2
Berounian449.7 *
Sandbian453
Zahorany †/ViniceLetna †456.2 *
Liben †458 *
Middle OrdovicianDarriwilian458.4
Dobrotivian458.5 *
Oretanian459.7 *
Sarka †461.7 *
DapingianKlabava †467.3
Arenigian468
Early OrdovicianFloian470
TremadocianUngurianTremadocian477.7
CambrianFurongianStage 10Batyrbaian485.4
Jiangshanian489.5
Aksaian490.7 *
Sakian492.2 *
Paibian494
MiaolingianGuzhangianAyusokkanianSeries 3 †497
499.5
DrumianZhanaarykian500.5
Tuesaian503
WuliuanStage 5 †504.5
505.3
Series 2Stage 4509
Toyonian510 *
Botomian512.5 *
Stage 3514
Atdabanian515.6 *
TerreneuvianStage 2Tommotian521
525.5