Geologic Time
| Type | Start (million yrs ago) | End (million yrs ago) | Total yrs (millions) | |
| Precambrian | 4600 | 542 | 4058 | |
| Hadeon | Eon | 4600 | 3800 | 800 |
| Archean | Eon | 3800 | 2500 | 1300 |
| Proterozoic | Eon | 2500 | 542 | 1958 |
| Phanerozoic | Eon | 542 | 251 | 291 |
| Cambrian | Period | 542 | 488 | 54 |
| Ordovician | Period | 488 | 443 | 45 |
| Silurian | Period | 443 | 416 | 27 |
| Devonian | Period | 416 | 359 | 57 |
| Carboniferous | Period | 359 | 299 | 60 |
| Permian | Period | 299 | 251 | 48 |
| Mesozoic | Era | 251 | 65.5 | 185.5 |
| Triassic | Period | 251 | 199 | 52 |
| Jurassic | Period | 199 | 145 | 54 |
| Cretaceous | Period | 145 | 65.5 | 79.5 |
| Cenozoic | Era | 65.5 | 0 | 65.5 |
| Paleogene | Period | 65.5 | 23 | 42.5 |
| Paleocene | Epoch | 65.5 | 55.8 | 9.7 |
| Eocene | Epoch | 55.8 | 33.9 | 21.9 |
| Oligocene | Epoch | 33.9 | 23 | 10.9 |
| Neogene | Period | 23 | 0 | 23 |
| Miocene | Epoch | 23 | 5.3 | 17.7 |
| Pliocene | Epoch | 5.3 | 1.8 | 3.5 |
| Pleistocene | Epoch | 1.8 | 0.018 | 1.782 |
| Holocene | Epoch | 0.012 | 0 | 0.012 |
