Geological Time Scale
This table contains the geological time periods of the past 2.5 billion years on Earth to aid in understanding age immense age of these fossils.
(Ma = Mega-annum = 1,000,000 years)| EON | ERA | PERIOD | EXTENT (Ma) | DURATION (Ma) |
|---|---|---|---|---|
| Phanerozoic | Cenozoic | Quaternary | 2.588–Present | 2.588+ |
| Neogene | 23.03–2.588 | 20.4 | ||
| Paleogene | 66.0–23.03 | 42.9 | ||
| Mesozoic | Cretaceous | 145.5–66.0 | 79.5 | |
| Jurassic | 201.3–145.0 | 56.3 | ||
| Triassic | 252.17–201.3 | 50.9 | ||
| Paleozoic | Permian | 298.9–252.17 | 46.7 | |
| Carboniferous | 358.9–298.9 | 60 | ||
| Devonian | 419.2–358.9 | 60.3 | ||
| Silurian | 443.4–419.2 | 24.2 | ||
| Ordovician | 485.4–443.4 | 42 | ||
| Cambrian | 541.0–485.4 | 55.6 | ||
| Proterozoic | Neoproterozoic | Ediacaran | 635.0–541.0 | 94 |
| Cryogenian | 850–635 | 215 | ||
| Tonian | 1,000–850 | 150 | ||
| Mesoproterozoic | Stenian | 1,200–1,000 | 200 | |
| Ectasian | 1,400–1,200 | 200 | ||
| Calymmian | 1,600–1,400 | 200 | ||
| Paleoproterozoic | Statherian | 1,800–1,600 | 200 | |
| Orosirian | 2,050–1,800 | 250 | ||
| Rhyacian | 2,300–2,050 | 250 | ||
| Siderian | 2,500–2,300 | 200 | ||