Time Scales
Eon/Eonothem | Era/Erathem | Sub‐era | Period/System | Epoch/Series | Starting Ma |
---|---|---|---|---|---|
PHANEROZOIC | Cenozoic | Quaternary | Pleistogene | Holocene | 0.01 |
Pleistocene | 1.8 | ||||
Tertiary | Neogene | Pliocene | 5.2 | ||
Miocene | 23.3 | ||||
Palaeogene | Oligocene | 35.4 | |||
Eocene | 56.5 | ||||
Palaeocene | 65 | ||||
Mesozoic | Cretaceous | 145.6 | |||
Jurassic | 208 | ||||
Triassic | 245 | ||||
Palaeozoic | Upper Palaeozoic | Permian | 290 | ||
Carboniferous | 362.5 | ||||
Devonian | 408.5 | ||||
Lower Palaeozoic | Silurian | 439 | |||
Ordovician | 510 | ||||
Cambrian | 570 | ||||
PROTEROZOIC | 2500 | ||||
ARCHAEAN | 4000 | ||||
PRISCOAN | 4600 | ||||
(After Harland et al., 1989) |
Eon/Eonothem | Era/Erathem | Sub‐era | Period/System | Epoch/Series | Starting Ma |
---|---|---|---|---|---|
PHANEROZOIC | Cenozoic | Quaternary | Pleistogene | Holocene | 0.01 |
Pleistocene | 1.64 | ||||
Tertiary | Neogene | Pliocene | 5.2 | ||
Miocene | 23.3 | ||||
Palaeogene | Oligocene | 35.4 | |||
Eocene | 56.5 | ||||
Palaeocene | 65 | ||||
Mesozoic | Cretaceous | 145.6 | |||
Jurassic | 208 | ||||
Triassic | 245 | ||||
Palaeozoic | Upper Palaeozoic | Permian | 290 | ||
Carboniferous | 362.5 | ||||
Devonian | 408.5 | ||||
Lower Palaeozoic | Silurian | 439 | |||
Ordovician | 510 | ||||
Cambrian | 570 | ||||
PROTEROZOIC | 2500 | ||||
ARCHAEAN | 4000 | ||||
PRISCOAN | 4600 | ||||
(After Harland et al., 1989) |
Stratigraphic mapping of the lunar surface has established the following Systems, in order of increasing age: | |
---|---|
System | Events |
The crystallization of the anorthositic lunar highland crust has been dated at 4.44 billion years. This event closely followed the formation of the Moon. | |
Copernican | Young ray craters (younger than about one billion years) |
Eratosthenian | Older post‐mare craters (about 1–3 billion years) |
Imbrian | Main mare basalt flooding, preceded by formation of the Imbrium and Orientale basins (3–3.85 billion years) |
Pre‐Imbrian: Nectarian | Formation of 11 major impact basins preceded by the Nectaris basin (3.85–3.92 billion years) |
Pre‐Nectarian | Formation of about 30 impact basins preceded by the Procellarum basin (before 3.92–4.2? billion years) |