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
- 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
- J. Palfy, P. L. Smith, and J. K. Mortensen. 2000. A U-Pb and 40Ar/39Ar time scale for the Jurassic. Canadian Journal of Earth Sciences 37(6):923-944 view
- M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
- J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 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.
This timescale is used in the definition of 127245 collections
| International Chronostratigraphic Timescale | Ammonite Chrons of North America | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Jurassic | Late Jurassic | Tithonian | 145 | |||||||
| Kimmeridgian | 149.2 | |||||||||
| Oxfordian | 154.8 | |||||||||
| Middle Jurassic | Callovian | 161.5 | ||||||||
| Bathonian | 165.3 | |||||||||
| Bajocian | Epizigzagiceras | 168.2 | ||||||||
| Rotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense | 168.4 | |||||||||
| Aalenian | Howelli/Scissum/Westermanni | 170.9 | ||||||||
| Early Jurassic | Toarcian | Yakounensis/Hillebrandti/Crassicosta | 174.7 | |||||||
| Planulata | 179.3 * | |||||||||
| Arnioceras arnouldi | 179.8 * | |||||||||
| Kanense | 181.3 * | |||||||||
| Carlottense | 182.3 * | |||||||||
| Kunae | 183.5 * | |||||||||
| Pliensbachian | 184.2 | |||||||||
| Freboldi | 185.1 * | |||||||||
| Whiteavesi/Imlayi | Tetraspidoceras | 186.2 * | ||||||||
| 189.2 * | ||||||||||
| Plesechioceras harbledownense/Asteroceras varians/Coroniceras | Canadensis | 190.3 * | ||||||||
| Sinemurian | 192.9 | |||||||||
| Pseudaetomoceras | Psiloceras | 196.4 * | ||||||||
| Franziceras/Euphyllites | 196.5 * | |||||||||
| Hettangian | 199.5 | |||||||||
| 201.4 | ||||||||||