Chadronian age - Orellan age
| International Chronostratigraphic Timescale | North American Land Mammal Ages | |||
|---|---|---|---|---|
| 18.5 | ||||
| Paleogene | Oligocene | Chattian | Arikareean | 23.03 |
| Rupelian | 27.82 | |||
| Whitneyan | 29.5 | |||
| Orellan | 31.8 | |||
| Eocene | Priabonian | Chadronian | 33.9 | |
| Duchesnean | 37 | |||
| Bartonian | 37.71 | |||
| Uintan | 39.7 | |||
| Lutetian | 41.2 | |||
| Bridgerian | 46.2 | |||
| Ypresian | 47.8 | |||
| Wasatchian | 50.5 | |||
| Clarkforkian | 54.9 | |||
| Paleocene | Thanetian | 56 | ||
| Tiffanian | 56.2 | |||
| Selandian | 59.2 | |||
| Torrejonian | 60.9 | |||
| Danian | 61.6 | |||
| Puercan | 63.8 | |||
| 66 | ||||