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
  • M. Freudenthal. 2006. Mammal Paleogene zones. personal communication 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. 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
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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 126175 collections

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International Chronostratigraphic TimescaleMesozoic SubagesMammal Paleogene ZonesTen Million Year BinsObsolete Precambrian AgesPermian of Western EuropeDevonian SubagesNorth American Mammal Subages/ZonesCretaceous SubepochsCarboniferous SubepochsObsolete Names for ICS Units
PhanerozoicCenozoicQuaternaryHoloceneMeghalayanCenozoic 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
PaleogeneOligoceneChattianMP 30/MP 29/MP 28/MP 27/MP 26MP 25Cenozoic 423.03
Monroecreekian23.1 *
Geringian24.7 *
RupelianMP 24/MP 23/MP 22/MP 2127.82
29.5
EocenePriabonianMP 20/MP 19/MP 18/MP 17B/MP 17ACenozoic 3Late Chadronian/Middle Chadronian/Early Chadronian33.9
37
BartonianMP 1637.71
Late Uintan/Early Uintan39.7
LutetianMP 15/MP 14/MP 13/MP 12/MP 11Cenozoic 241.2
Twinbuttean/Blacksforkian/Gardnerbuttian46.2
YpresianMP 10/MP 8 + 9/MP 747.8
Lostcabinian/Lysitean/Graybullian/Sandcouleean50.5
Cf3/Cf2/Cf154.9
PaleoceneThanetianMP 6MP 1 - 5Cenozoic 156
Ti6/Ti5/Ti4/Ti3/Ti2/Ti156.2
Selandian59.2
To3/To2/To160.9
Danian61.6
Pu3/Pu2/Pu163.8
MesozoicCretaceousLate CretaceousMaastrichtianLate Maastrichtian/Early MaastrichtianCretaceous 8Senonian66
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 4Gallic100.5
Middle Albian106.2 *
Early Albian109.9 *
AptianLate AptianCretaceous 3113
Early Aptian119.5 *
BarremianLate Barremian/Early BarremianCretaceous 2121.4
HauterivianLate Hauterivian/Early HauterivianNeocomian125.77
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 *
PaleozoicPermianLopingianChanghsingianPermian 4251.902
WuchiapingianZechsteinLongtanian †254.14
GuadalupianCapitanianRotliegendes259.51
Wordian264.28
RoadianPermian 3266.9
CisuralianKungurianPermian 2273.01
ArtinskianAutunian283.5
Sakmarian290.1
AsselianPermian 1293.52
CarboniferousPennsylvanianGzhelianCarboniferous 5Late Pennsylvanian298.9
Kasimovian303.7
MoscovianCarboniferous 4Middle Pennsylvanian307
BashkirianEarly Pennsylvanian315.2
MississippianSerpukhovianCarboniferous 3Late Mississippian323.2
ViseanCarboniferous 2Middle Mississippian330.9
TournaisianCarboniferous 1Early Mississippian346.7
DevonianLate DevonianFamennianDevonian 5Late Famennian358.9
Middle Famennian365.3 *
Early Famennian368.5 *
FrasnianDevonian 4Late Frasnian372.2
Middle Frasnian375.4 *
Early Frasnian379.3 *
Middle DevonianGivetianDevonian 3Late Givetian382.7
Middle Givetian383.7 *
Early Givetian385.9 *
EifelianLate Eifelian387.7
Early Eifelian390.3 *
Early DevonianEmsianDevonian 2Late Emsian393.3
Early Emsian398.3 *
PragianDevonian 1Pragian407.6
LochkovianLate Lochkovian410.8
Middle Lochkovian412.8 *
Early Lochkovian415.6 *
SilurianPridoliSilurian 2419.2
LudlowLudfordian423
Gorstian425.6
WenlockHomerian427.4
Sheinwoodian430.5
LlandoveryTelychianSilurian 1433.4
Aeronian438.5
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianOrdovician 5443.8
Katian445.2
SandbianOrdovician 4453
Middle OrdovicianDarriwilianOrdovician 3458.4
DapingianOrdovician 2467.3
Early OrdovicianFloian470
TremadocianOrdovician 1477.7
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
ProterozoicNeoproterozoicEdiacaranVendian †Poundian †538.8
Wonokan †571.7 *
635