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
- 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
- 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
- M. Kretzoi. 1942. Necroteuthis n. g. (Ceph. Dibr., Necroteuthidae N. F.) aus dem Oligozän von Budapest und das system der Dibranchiata. Földtani Közlöny 72:125-238 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
| International Chronostratigraphic Timescale | Ordovician of Australia | Ordovician of China | Ordovician of North America | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ordovician | Late Ordovician | Hirnantian | Bolindian | Hirnantian | Xiaoxita †/Shikou | Wufeng † | Cincinnatian | Gamachian | 443.8 | |||||||||
| Katian | Chientangkiangian | 445.2 | ||||||||||||||||
| Richmondian | 446 * | |||||||||||||||||
| Eastonian | 449 * | |||||||||||||||||
| Neichianshanian/Hanjiang | 449.5 | |||||||||||||||||
| Maysvillian | Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian | 449.8 * | ||||||||||||||||
| Edenian | 450.4 * | |||||||||||||||||
| Mohawkian | Chatfieldian | 451.1 * | ||||||||||||||||
| Gisbornian | 452 * | |||||||||||||||||
| Sandbian | 453 | |||||||||||||||||
| Turinian | 453.7 * | |||||||||||||||||
| Whiterockian | Canadian † | Chazyan †/Marmor | 457 * | |||||||||||||||
| Middle Ordovician | Darriwilian | Darriwilian | Darriwilian | Guniu †/Hulo | 458.4 | |||||||||||||
| Hunjiang † | Dawan †/Daobaowan/Ningkuo | 466.3 * | ||||||||||||||||
| Dapingian | Yapeenian | Dapingian | 467.3 | |||||||||||||||
| Castlemainian | 468.5 * | |||||||||||||||||
| Rangerian | 469.1 * | |||||||||||||||||
| Early Ordovician | Floian | Chewtonian | Yiyangian | Ibexian | Blackhillsian | Jeffersonian † | Cassinian † | 470 | ||||||||||
| Bendigonian | 471.8 * | |||||||||||||||||
| Lancefieldian | 473.5 * | |||||||||||||||||
| Tulean | 473.9 * | |||||||||||||||||
| Tremadocian | Xinchangian | 477.7 | ||||||||||||||||
| Lianghekou † | 477.9 * | |||||||||||||||||
| Stairsian | 480.3 * | |||||||||||||||||
| Skullrockian/Demingian | 482 * | |||||||||||||||||
| Warendian | 482.8 * | |||||||||||||||||
| 485.4 | ||||||||||||||||||
| 487.5 | ||||||||||||||||||