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, F. P. Agterberg, J. G. Ogg, J. Hardenbol, P. Van Veen, J. Thierry, and Z. Huang. 1995. A Triassic, Jurassic, and Cretaceous time scale. SEPM Special Publication 54 view
- F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 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
- 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. 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 | Mesozoic Subages | Ammonite Chrons of North America | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Jurassic | Late Jurassic | Tithonian | Late Tithonian | Middle Tithonian | 145 | |||||||
| Early Tithonian | 146.3 * | |||||||||||
| Kimmeridgian | Late Kimmeridgian | 149.2 | ||||||||||
| Early Kimmeridgian | 152.2 * | |||||||||||
| Oxfordian | Late Oxfordian | Middle Oxfordian/Early Oxfordian | 154.8 | |||||||||
| 157.9 * | ||||||||||||
| Middle Jurassic | Callovian | Late Callovian/Middle Callovian/Early Callovian | 161.5 | |||||||||
| Bathonian | Late Bathonian/Middle Bathonian/Early Bathonian | 165.3 | ||||||||||
| Bajocian | Late Bajocian | Epizigzagiceras | 168.2 | |||||||||
| Rotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense | 168.4 | |||||||||||
| Early Bajocian | 168.6 * | |||||||||||
| Aalenian | Late Aalenian/Middle Aalenian/Early Aalenian | Howelli/Scissum/Westermanni | 170.9 | |||||||||
| Early Jurassic | Toarcian | Late Toarcian | Yakounensis/Hillebrandti/Crassicosta | 174.7 | ||||||||
| Planulata | 179.3 * | |||||||||||
| Arnioceras arnouldi | 179.8 * | |||||||||||
| Middle Toarcian | 180.4 * | |||||||||||
| Kanense | 181.3 * | |||||||||||
| Carlottense | 182.3 * | |||||||||||
| Early Toarcian | 182.9 * | |||||||||||
| Kunae | 183.5 * | |||||||||||
| Pliensbachian | Late Pliensbachian/Early Pliensbachian | 184.2 | ||||||||||
| Freboldi | 185.1 * | |||||||||||
| Whiteavesi/Imlayi | Tetraspidoceras | 186.2 * | ||||||||||
| 189.2 * | ||||||||||||
| Plesechioceras harbledownense/Asteroceras varians/Coroniceras | Canadensis | 190.3 * | ||||||||||
| Sinemurian | Late Sinemurian/Early Sinemurian | 192.9 | ||||||||||
| Pseudaetomoceras | Psiloceras | 196.4 * | ||||||||||
| Franziceras/Euphyllites | 196.5 * | |||||||||||
| Hettangian | Late Hettangian/Middle Hettangian/Early Hettangian | 199.5 | ||||||||||
| 201.4 | ||||||||||||