Get ready for a journey through Geologic Time from the Precambrian era to the Cenozoic Era
But first lets teach you some thing you need to know before we start.
What is Geologic Time?
Geologic time is the whole history of earth it started when the earth is formed.A geologic time scale is different from geologic time geologic time scale help scientist classify events in geologic time.
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Fossils and fossil records used as evidence to explain theories fossils an fossils records are used as windows to look into the past and tell what lived in that era.
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law of superposition is that the oldest rock is on the bottom of the rock and the youngest is on the top an every thing between has been lied after the oldest rock and before the new rock and new rock pusses the old rock down.
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How scientist decide when a era ends and a new era begins. Scientist decide when eras end a new eras start when a mass extinction occurs a mass extinction is when many species die forever it happens from when the land changes and climates change the most famous mass extinction the mesozoic mass extinction when the dinosaurs became extinct.