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
- 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
- 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
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 126755 collections
| International Chronostratigraphic Timescale | Ordovician of North America | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Ordovician | Late Ordovician | Hirnantian | Cincinnatian | Gamachian | 443.8 | ||||
| Katian | 445.2 | ||||||||
| Richmondian | 446 * | ||||||||
| Maysvillian | Rocklandian †/Shermanian/Ashbyan/Kirkfieldian/Blackriveran/Wildernessian/Trentonian/Franklinian | 449.8 * | |||||||
| Edenian | 450.4 * | ||||||||
| Mohawkian | Chatfieldian | 451.1 * | |||||||
| Sandbian | 453 | ||||||||
| Turinian | 453.7 * | ||||||||
| Whiterockian | Canadian † | Chazyan †/Marmor | 457 * | ||||||
| Middle Ordovician | Darriwilian | 458.4 | |||||||
| Dapingian | 467.3 | ||||||||
| Rangerian | 469.1 * | ||||||||
| Early Ordovician | Floian | Ibexian | Blackhillsian | Jeffersonian † | Cassinian † | 470 | |||
| Tulean | 473.9 * | ||||||||
| Tremadocian | 477.7 | ||||||||
| Stairsian | 480.3 * | ||||||||
| Skullrockian/Demingian | 482 * | ||||||||
| 485.4 | |||||||||
| 487.5 | |||||||||