EON
ERA
PERIOD
Ma
CENOZOIC
Quaternary, Neogene & Paleogene
66
MESOZOIC
Cretaceous
145
Jurassic
200
Triassic
251
PALEOZOIC
Permian
299
Carboniferous
359
Devonian
416
Silurian
444
Ordovician
488
Cambrian
542
