Unformatted text preview: ~ 570 Ma Proterozoic _______________________________________________ ~ 2.5 Ga Archean _______________________________________________ ~ 3.8 ? Ga Pre-Archean _______________________________________________ 4.5 Ga Please Note: There is some disagreement as the placement of the Quaternary – Tertiary boundary. Some propose to move it back to the first appearance of widespread glaciation, which occur at about 2.5 Ma...
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- Fall '09
- Geologic Time Scale, Gondwana, Pliocene Cenozoic Tertiary Miocene Oligocene Eocene Paleocene, Permian Pennsylvanian Paleozoic Mississippian Devonian Silurian Ordovician Cambrian, Pliocene Cenozoic Tertiary