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
- 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. Freudenthal. 2006. Mammal Paleogene zones. personal communication view
- F. F. Steininger, W. A. Berggren, D. V. Kent, R. L. Bernor, S. Sen and J. Agusti. 1996. Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units. The Evolution of Western Eurasian Neogene Mammal Faunas (eds. R. L. Bernor, V. Fahlbusch, and H.-W. Mittmann) 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.
Interval names marked with † are no longer in current use.
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 | ||||||||||