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
  • B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 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
  • J. I. Raine, A. G. Beu, A. F. Boyes, H. J. Campbell, R. A. Cooper, J. S. Crampton, M. P. Crundwell, C. J. Hollis, and H. E. G. Morgans. 2015. Revised Calibration of the New Zealand Geological Timescale: NZGT2015/1. GNS Science Report 2012(39) view
  • F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 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. Harzhauser and W. E. Piller. 2004. Integrated stratigraphy of the Sarmatian (Upper Middle Miocene) in the western Central Paratethys. Stratigraphy 1(1):65-86 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 TimescaleOrdovician of ChinaOrdovician of the BalticOrdovician of Ibero-Bohemia
OrdovicianLate OrdovicianHirnantianHirnantianXiaoxita †/ShikouWufeng †HarjuPorkuniKosovian443.8
KatianChientangkiangianPirguKralodvorianBohdalec †445.2
Neichianshanian/Hanjiang449.5
Vormsi449.6 *
Berounian449.7 *
NabalaJohvi †450 *
ViruRakvere450.6 *
Oandu452 *
SandbianKeilaIdavere †453
Haljala453.9
Zahorany †/ViniceLetna †456.2 *
Kukruse456.4 *
UhakuAluoja †457.5 *
Liben †458 *
Middle OrdovicianDarriwilianDarriwilianGuniu †/Hulo458.4
Dobrotivian458.5 *
Lasnamagi458.9 *
Oretanian459.7 *
Aseri460.4 *
Sarka †461.7 *
OelandKunda462.9 *
Valaste †/Hunderum464.3 *
Hunjiang †Dawan †/Daobaowan/Ningkuo466.3 *
VolkhovLangevoja †/Vaana/Saka467.1 *
DapingianDapingianKlabava †467.3
Arenigian468
Billingen469.3 *
Early OrdovicianFloianYiyangian470
Latorp †470.1 *
Hunneberg473.7 *
TremadocianXinchangianTremadocian477.7
Lianghekou †477.9 *
Varangu481.3 *
Pakerort482.2 *
485.4 *
486.3
486.5