Obsolete Names for ICS Units

The interval definitions in this timescale are derived from the following sources:

  • 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
  • K. M. Cohen, S.C. Finney, P.L. Gibbard and J.-X. Fan. 2023. The ICS International Chronostratigraphic Chart v2023/09. 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, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
  • B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
  • F. J. Prevosti, C. O. Romano, A. M. Forasiepi, S. Hemming, R. Bonini, A. M. Candela, E. Cerdeño, M. C. Madozzo Jaén, P. E. Ortiz, F. Pujos, L. Rasia, G. I. Schmidt, M. Taglioretti, R. D. E. MacPhee, and U. F. J. Pardiñas. 2021. New radiometric 40Ar–39Ar dates and faunistic analyses refine evolutionary dynamics of Neogene vertebrate assemblages in southern South America. Scientific Reports 2021(11):9830 view
  • J. J. Flynn and C. C. Swisher, III. 1995. Cenozoic South American Land Mammal Ages: correlation to global geochronology. Geochronology Time Scales and Global Stratigraphic Correlation, SEPM Special Publication 54:317-333 view
  • J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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

There are 55 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 92 collections

Show more time

Show linear time

International Chronostratigraphic TimescaleObsolete Names for ICS UnitsNorth American Mammal Subages/ZonesOrdovician of the BalticSouth American Land Mammal AgesPermian of the Salt RangeSilurian of EnglandCretaceous North American Land-Mammal AgesCambrian EpochsAmmonite Chrons of North AmericaOrdovician of Britain
QuaternaryPleistoceneLate PleistoceneSheridanianLujanian0.0117
Chibanian0.129
Cudahyan/Sappan0.21
Ensenadan0.3 *
Calabrian0.774
Senecan/Rexroadian1.4
SanandresianUquian †1.7 *
Gelasian1.8
NeogenePliocenePiacenzianTertiary †Vorohuean2.58
Chapadmalalan2.9 *
Zanclean3.6
Montehermosan3.7 *
Late Hemphillian/late Early Hemphillian/early Early Hemphillian4.7
Huayquerian4.9 *
MioceneMessinian5.333
Tortonian7.246
Chasicoan7.9 *
Late Clarendonian/Early Clarendonian9.4
Mayoan9.9 *
Laventan10.9 *
Serravallian11.63
late Late Barstovian/early Late Barstovian/Early Barstovian12.5
Colloncuran13.7 *
Langhian13.82
Friasian15.4 *
Burdigalian15.98
Santacrucian16.2 *
Late Hemingfordian/Early Hemingfordian16.3
Colhuehuapian17.4 *
late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonian18.5
Aquitanian20.44
Deseadan20.9 *
PaleogeneOligoceneChattian23.03
Monroecreekian23.1 *
Geringian24.7 *
Rupelian27.82
Tinguirirican28.9 *
29.5
EocenePriabonianLate Chadronian/Middle Chadronian/Early Chadronian33.9
Divisaderan35.9 *
37
Bartonian37.71
Late Uintan/Early Uintan39.7
Lutetian41.2
Mustersan41.9 *
Twinbuttean/Blacksforkian/Gardnerbuttian46.2
Ypresian47.8
Casamayoran47.9 *
Lostcabinian/Lysitean/Graybullian/Sandcouleean50.5
Cf3/Cf2/Cf154.9
PaleoceneThanetianRiochican56
Ti6/Ti5/Ti4/Ti3/Ti2/Ti156.2
Itaboraian56.9 *
Peligran58.9 *
Selandian59.2
To3/To2/To160.9
Danian61.6
Tiupampan62.4 *
Pu3/Pu2/Pu163.8
CretaceousLate CretaceousMaastrichtianLancian/Edmontonian66
CampanianJudithian/Aquilan72.1
Santonian83.6
Coniacian86.3
Turonian89.8
Cenomanian93.9
Early CretaceousAlbian100.5
Aptian113
Barremian121.4
Hauterivian125.77
Valanginian132.6
Berriasian139.8
JurassicLate JurassicTithonian145
Kimmeridgian149.2
Oxfordian154.8
Middle JurassicCallovian161.5
Bathonian165.3
BajocianEpizigzagiceras168.2
Rotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense168.4
AalenianHowelli/Scissum/Westermanni170.9
Early JurassicToarcianYakounensis/Hillebrandti/Crassicosta174.7
Planulata179.3 *
Arnioceras arnouldi179.8 *
Kanense181.3 *
Carlottense182.3 *
Kunae183.5 *
Pliensbachian184.2
Freboldi185.1 *
Whiteavesi/ImlayiTetraspidoceras186.2 *
189.2 *
Plesechioceras harbledownense/Asteroceras varians/CoronicerasCanadensis190.3 *
Sinemurian192.9
PseudaetomocerasPsiloceras196.4 *
Franziceras/Euphyllites196.5 *
Hettangian199.5
TriassicLate TriassicRhaetian201.4
Norian208.5
Carnian227
Middle TriassicLadinian237
Anisian242
Early TriassicOlenekian247.2
Induan251.2
Kathwai251.5 *
PermianLopingianChanghsingian251.902
252.4 *
Chhidru252.9 *
WuchiapingianLongtanian †254.14
Kalabagh255 *
Wargal256 *
GuadalupianCapitanian259.51
Wordian264.28
265.3 *
Amb266.1 *
Roadian266.9
270.7 *
CisuralianKungurian273.01
Artinskian283.5
Sakmarian290.1
Asselian293.52
CarboniferousPennsylvanianGzhelian298.9
Kasimovian303.7
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennian358.9
Frasnian372.2
Middle DevonianGivetian382.7
Eifelian387.7
Early DevonianEmsian393.3
Pragian407.6
Lochkovian410.8
SilurianPridoliRed Downtonian/Temeside Shales/Downton CastleWhitcliffe/Leintwardine419.2
Bringewood/Elton421.3
LudlowLudfordianCoalbrookdaleWenlock (England)/Tickwood423
Gorstian425.6
Buildwas426.4 *
WenlockHomerian427.4
WychWoolhope428.4 *
Sheinwoodian430.5
LlandoveryTelychian433.4
436.3 *
Aeronian438.5
Cowleigh Park439.3 *
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianHarjuPorkuniAshgillHirnantian443.8
KatianPirguRawtheyan445.2
Cautleyan448.9 *
Pusgillian449.3 *
VormsiCaradocStreffordianOnnian †449.6 *
NabalaJohvi †450 *
ViruRakvere450.6 *
Cheneyan451.5 *
Oandu452 *
Burrellian452.7 *
SandbianKeilaIdavere †453
Actonian †453.2 *
Haljala453.9
Marshbrookian †Woolstonian †454.2 *
Longvillian †455.2 *
Kukruse456.4 *
Aurelucian456.8 *
Soudleyan †/Harnagian/Costonian457.4 *
UhakuAluoja †457.5 *
Middle OrdovicianDarriwilianLlanvirnLlandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn458.4
Lasnamagi458.9 *
Aseri460.4 *
Abereiddian/Early Llanvirn461.3 *
OelandKunda462.9 *
Valaste †/Hunderum464.3 *
VolkhovLangevoja †/Vaana/Saka467.1 *
Dapingian467.3
ArenigFennian468.4 *
Billingen469.3 *
Early OrdovicianFloian470
Latorp †470.1 *
Whitlandian471.1 *
Hunneberg473.7 *
Moridunian474.3 *
TremadocianTremadocMigneintian477.7
Cressagian480.8 *
Varangu481.3 *
Pakerort482.2 *
485 *
CambrianFurongianStage 10Late Cambrian485.4
486.3 *
486.5
Jiangshanian489.5
Paibian494
MiaolingianGuzhangianSeries 3 †Middle Cambrian497
Drumian500.5
WuliuanStage 5 †504.5
Series 2Stage 4Early Cambrian509
Stage 3514
TerreneuvianStage 2521
Fortunian529
538.8