Duchesnean age - Chadronian age
| International Chronostratigraphic Timescale | North American Land Mammal Ages | |||
|---|---|---|---|---|
| 18.5 | ||||
| Paleogene | Oligocene | Chattian | Arikareean | 23.04 |
| Rupelian | 27.3 | |||
| Whitneyan | 29.5 | |||
| Orellan | 31.8 | |||
| Eocene | Priabonian | Chadronian | 33.9 | |
| Duchesnean | 37 | |||
| Bartonian | 37.71 | |||
| Uintan | 39.7 | |||
| Lutetian | 41.03 | |||
| Bridgerian | 45.9 | |||
| Ypresian | 48.07 | |||
| Wasatchian | 51.1 | |||
| Paleocene | Thanetian | Clarkforkian | 56 | |
| Tiffanian | 57.5 | |||
| Selandian | 59.24 | |||
| Torrejonian | 60.9 | |||
| Danian | 61.66 | |||
| Puercan | 63.4 | |||
| 66 | ||||