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

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International Chronostratigraphic TimescaleObsolete Names for ICS UnitsSilurian of North AmericaOrdovician of Ibero-BohemiaOrdovician of BritainOrdovician of the BalticPermian of the Russian PlatformOrdovician of ChinaDevonian of CzechoslovakiaMammal Paleogene Zones
NeogenePliocenePiacenzianTertiary †2.58
Zanclean3.6
MioceneMessinian5.333
Tortonian7.246
Serravallian11.63
Langhian13.82
Burdigalian15.98
Aquitanian20.44
PaleogeneOligoceneChattianMP 30/MP 29/MP 28/MP 27/MP 26MP 2523.03
RupelianMP 24/MP 23/MP 22/MP 2127.82
EocenePriabonianMP 20/MP 19/MP 18/MP 17B/MP 17A33.9
BartonianMP 1637.71
LutetianMP 15/MP 14/MP 13/MP 12/MP 1141.2
YpresianMP 10/MP 8 + 9/MP 747.8
PaleoceneThanetianMP 6MP 1 - 556
Selandian59.2
Danian61.6
CretaceousLate CretaceousMaastrichtian66
Campanian72.1
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
Bajocian168.2
Aalenian170.9
Early JurassicToarcian174.7
Pliensbachian184.2
Sinemurian192.9
Hettangian199.5
TriassicLate TriassicRhaetian201.4
Norian208.5
Carnian227
Middle TriassicLadinian237
Anisian242
Early TriassicOlenekian247.2
Induan251.2
PermianLopingianChanghsingian251.902
WuchiapingianLongtanian †254.14
TatarianVyatkian256.8 *
GuadalupianCapitanianSeverodvinian259.51
WordianUrzhumian264.28
RoadianKazanianPovolzhian266.9
Sokian270.7 *
CisuralianKungurianKungurianIrenian/Ufimian273.01
Filipovian276.5 *
Saraninian280.1 *
ArtinskianArtinskianSarginian283.5
Irginian285.9 *
Burtsevian287.8 *
SakmarianSakmarianSterlitamakian290.1
Tastubian291.7 *
AsselianAsselianShikhanian293.52
Uskalykian294.8
Surenian297.5
CarboniferousPennsylvanianGzhelian298.9
Kasimovian303.7
Moscovian307
Bashkirian315.2
MississippianSerpukhovian323.2
Visean330.9
Tournaisian346.7
DevonianLate DevonianFamennian358.9
Frasnian372.2
Middle DevonianGivetianSrbsko382.7
EifelianChotec387.7
Early DevonianEmsianDaleje/Zlichovian393.3
PragianPragian407.6
LochkovianLochkovian410.8
SilurianPridoliCayugan419.2
Niagaran422.5 *
LudlowLudfordian423
Gorstian425.6
WenlockHomerianLockportian427.4
Sheinwoodian430.5
LlandoveryTelychianOntarian433.4
Aeronian438.5
Alexandrian438.7 *
MedinanClinton440.1 *
440.7 *
Rhuddanian440.8
OrdovicianLate OrdovicianHirnantianKosovianAshgillHirnantianHarjuPorkuniHirnantianXiaoxita †/ShikouWufeng †443.8
KatianKralodvorianBohdalec †RawtheyanPirguChientangkiangian445.2
Cautleyan448.9 *
Pusgillian449.3 *
Neichianshanian/Hanjiang449.5
CaradocStreffordianOnnian †Vormsi449.6 *
Berounian449.7 *
NabalaJohvi †450 *
ViruRakvere450.6 *
Cheneyan451.5 *
Oandu452 *
Burrellian452.7 *
SandbianKeilaIdavere †453
Actonian †453.2 *
Haljala453.9
Marshbrookian †Woolstonian †454.2 *
Longvillian †455.2 *
Zahorany †/ViniceLetna †456.2 *
Kukruse456.4 *
Aurelucian456.8 *
Soudleyan †/Harnagian/Costonian457.4 *
UhakuAluoja †457.5 *
Liben †458 *
Middle OrdovicianDarriwilianLlanvirnLlandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late LlanvirnDarriwilianGuniu †/Hulo458.4
Dobrotivian458.5 *
Lasnamagi458.9 *
Oretanian459.7 *
Aseri460.4 *
Abereiddian/Early Llanvirn461.3 *
Sarka †461.7 *
OelandKunda462.9 *
Valaste †/Hunderum464.3 *
Hunjiang †Dawan †/Daobaowan/Ningkuo466.3 *
VolkhovLangevoja †/Vaana/Saka467.1 *
DapingianKlabava †Dapingian467.3
Arenigian468
ArenigFennian468.4 *
Billingen469.3 *
Early OrdovicianFloianYiyangian470
Latorp †470.1 *
Whitlandian471.1 *
Hunneberg473.7 *
Moridunian474.3 *
TremadocianTremadocianTremadocMigneintianXinchangian477.7
Lianghekou †477.9 *
Cressagian480.8 *
Varangu481.3 *
Pakerort482.2 *
485 *
CambrianFurongianStage 10485.4
486.3 *
486.5
Jiangshanian489.5
Paibian494
MiaolingianGuzhangianSeries 3 †497
Drumian500.5
WuliuanStage 5 †504.5
509