Geologic Time Scale

Pre-Cambrian

Era, 4600mya-541may

Phanerozoic

Eon, 541mya-0.01mya

Paleozoic

Era, 541mya-251.9mya, within Phanerozoic

Mesozoic

Era, 251.9mya-66may, within Phanerozoic

Cenozoic

Era, 66may-present, within Phanerozoic

Cambrian

1st period, within Paleozoic, followed by ordovician

Ordovician

2nd period, within Paleozoic, between Cambrian and Silurian

Silurian

3rd period, within Paleozoic, between Ordovician and Devonian

Devonian

4th period, within Paleozoic, between Silurian and Mississippian

Mississippian

5th period, within Paleozoic, between Devonian and Pennsylivanian

Pennsylvanian

6th period, within Paleozoic, between Mississippian and Permian

Permian

6th period, within Paleozoic, between Pennsylvanian and Triassic

Triassic

7th period, within Mesozoic, between Permian and Jurassic

Jurassic

8th period, within Mesozoic, between Triassic and Cretaceous

Cretaceous

9th period, within Mesozoic, between Jurassic and tertiary

Tertiary

10th period, within Cenozoic, between Cretaceous and Quaternary

Quaternary

11th period, within Cenozoic, after Tertiary

Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Tertiary, Quanternary

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