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
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 126585 collections
| International Chronostratigraphic Timescale | Ordovician of Britain | Ten Million Year Bins | Ordovician of Ibero-Bohemia | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ordovician | Late Ordovician | Hirnantian | Ashgill | Hirnantian | Ordovician 5 | Kosovian | 443.8 | |||||||||
| Katian | Rawtheyan | Kralodvorian | Bohdalec † | 445.2 | ||||||||||||
| Cautleyan | 448.9 * | |||||||||||||||
| Pusgillian | 449.3 * | |||||||||||||||
| Caradoc | Streffordian | Onnian † | 449.6 * | |||||||||||||
| Berounian | 449.7 * | |||||||||||||||
| Cheneyan | 451.5 * | |||||||||||||||
| Burrellian | 452.7 * | |||||||||||||||
| Sandbian | Ordovician 4 | 453 | ||||||||||||||
| Actonian † | 453.2 * | |||||||||||||||
| Marshbrookian † | Woolstonian † | 454.2 * | ||||||||||||||
| Longvillian † | 455.2 * | |||||||||||||||
| Zahorany †/Vinice | Letna † | 456.2 * | ||||||||||||||
| Aurelucian | 456.8 * | |||||||||||||||
| Soudleyan †/Harnagian/Costonian | 457.4 * | |||||||||||||||
| Liben † | 458 * | |||||||||||||||
| Middle Ordovician | Darriwilian | Llanvirn | Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn | Ordovician 3 | 458.4 | |||||||||||
| Dobrotivian | 458.5 * | |||||||||||||||
| Oretanian | 459.7 * | |||||||||||||||
| Abereiddian/Early Llanvirn | 461.3 * | |||||||||||||||
| Sarka † | 461.7 * | |||||||||||||||
| Dapingian | Ordovician 2 | Klabava † | 467.3 | |||||||||||||
| Arenigian | 468 | |||||||||||||||
| Arenig | Fennian | 468.4 * | ||||||||||||||
| Early Ordovician | Floian | 470 | ||||||||||||||
| Whitlandian | 471.1 * | |||||||||||||||
| Moridunian | 474.3 * | |||||||||||||||
| Tremadocian | Tremadoc | Migneintian | Ordovician 1 | Tremadocian | 477.7 | |||||||||||
| Cressagian | 480.8 * | |||||||||||||||
| 485 * | ||||||||||||||||
| 485.4 | ||||||||||||||||