Figure 1. Typical classification by contemporary geologists. After Henry Faul, pp. 69-71.
| Era
| System or Period |
Series or Epoch |
Estimated Radiometric |
|
| |
|
Ages of Time Boundaries in |
|
| |
|
Millions of Years |
| Cenozoic |
|
Recent |
|
| Quaternary |
Pleistocene |
2 ± 1 |
|
Pliocene |
7 ± 1 |
|
Miocene |
26 ± 1 |
| Tertiary |
Oligocene |
38 ± 2 |
|
Eocene |
55 ± 2 |
|
Paleocene |
65 ± 2 |
| Mesozoic |
Cretaceous |
|
135 ± 5 |
| Jurassic |
|
190 ± 5 |
| Triassic |
|
225 ± 5 |
|
Permian |
|
270 ± 5 |
| Carboniferous |
Pennsylvanian |
|
320 ± 10 |
|
Mississippian |
|
340 ± 10 |
| Paleozoic |
Devonian |
|
400 ± 10 |
|
Silurian |
|
430 ± 10 |
|
Ordovician |
|
500 (?) |
|
Cambrian |
|
600 (?) |
| Precambrian |
|
|
|