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
- J. A. Lillegraven and M. C. McKenna. 1986. Fossil mammals from the "Mesaverde" Formation (Late Cretaceous, Judithian) of the Bighorn and Wind River basins, Wyoming, with definitions of Late Cretaceous North American Land-Mammal "Ages". American Museum Novitates 2840:1-68 view
- Z.-X. Qiu and Z.-D. Qiu. 1995. Chronological sequence and subdivision of Chinese Neogene mammalian faunas. Palaeogeography, Palaeoclimatology, Palaeoecology 116(1-2):41-70 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
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 | Ten Million Year Bins | Ammonite Chrons of North America | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Jurassic | Late Jurassic | Tithonian | Jurassic 6 | 145 | ||||||
| Kimmeridgian | Jurassic 5 | 149.2 | ||||||||
| Oxfordian | 154.8 | |||||||||
| Middle Jurassic | Callovian | 161.5 | ||||||||
| Bathonian | Jurassic 4 | 165.3 | ||||||||
| Bajocian | Epizigzagiceras | 168.2 | ||||||||
| Rotundum/Oblatum/Kirschneri/Crassicostatus/Widebayense | 168.4 | |||||||||
| Aalenian | Jurassic 3 | 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 | Jurassic 2 | 184.2 | ||||||||
| Freboldi | 185.1 * | |||||||||
| Whiteavesi/Imlayi | Tetraspidoceras | 186.2 * | ||||||||
| 189.2 * | ||||||||||
| Plesechioceras harbledownense/Asteroceras varians/Coroniceras | Canadensis | 190.3 * | ||||||||
| Sinemurian | Jurassic 1 | 192.9 | ||||||||
| Pseudaetomoceras | Psiloceras | 196.4 * | ||||||||
| Franziceras/Euphyllites | 196.5 * | |||||||||
| Hettangian | 199.5 | |||||||||
| 201.4 | ||||||||||