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Socials g9 geography
geologic time
Question | Answer |
---|---|
name the 4 eras for geologic time? | cenozoic, mesozoic, paleozoic and precambrian. |
Explain the dates time and the 3 major events of the cenozoic era? | 66 million years. ice sheets covered most of N. America continents take on present shape and the completion of the rocky mountains. |
Explain the dates time and 3 major events of the mesozoic era? | 66-245 million years. start of rocky mountain formation, innuation mountains formed and shallow seas in N. American interior. |
Explain the dates time and the 2 major events of the paleozoic era? | 245-570 million years. large portions of N. America covered by shallow seas and appalachians mountains formed. |
Explain the dates time and the major event of the precambrian era? | 570-4600 million years.precambrian shields formed(african shield and laurentian shield) |