Eon	Era Period Epoch
Phaenerozoic 0 - 0.57 Gy	Cenozoic   Quaternary 0 - 2.5 Ma      Holocene 0-10 Ka Pleistocene 10 Ka - 2.5 Ma   Tertiary 2.5 - 65 Ma          Africa, India & Asia collide Mesozoic  Cretaceous144-65 Ma       Gondwana breaks up Jurassic 213-144 Ma N. & S. America separate     Triassic 248-213 Ma Pangea forms Paleozoic  Permian 286-248 Ma Major Glaciation Carboniferous 360-286 Ma Coal Formation Devonian 408-360 Ma Laurasia Forms Silurian 438-408 Ma Plants invade land Ordovician 505-438 Ma Gondwana drifts over S.pole Cambrian 570-505 Ma Gondwanaland Forms
Proterozoic 0.57 - 2.5 Gy
Archean 2.5 - 3.8 Gy
Hadean 3.8 - 4.5 Gy

ERA	SYSTEM      SERIES       STAGE
Cenozoic	Neogene Holocene 0-10ka Pleistocene .01-1.8ma Upper Middle Lower Pliocene 1.8-5.3ma Upper Middle Lower Miocene 5.3-23.8ma Gelasian Piancenzian Zanclean Q U A T Paleogene Oligocene 23.8-33.7 ma Eocene 33.7-54.8 ma Paleocene 54.8-65 ma