1. North America’s Geologic History
Geologic history is broken down into 4 major time periods (eras):
Precambrian (earliest life)
Paleozoic (ancient life)
Mesozoic (middle life)
Cenozoic (recent life)

2. Precambrian (earliest life)

3. Paleozoic (ancient life)

4. Mesozoic (middle life)

5. Cenozoic (recent life)

6. Let’s read about North America’s Geologic History together
Textbook pages

7. Earth is estimated to be 4.6 billion years old.
How old is Earth?
Earth is estimated to be 4.6 billion years old.
How many times would the length of your life fit into Earth’s lifespan of years?
/ 15 = times.

8. Which era has so far been the longest?
The Precambrian Era (earliest life)
Began 4, 600 million years ago and ended
570 million years ago. This era lasted just over
4, 000 million years. (4, 030 to be exact)

9. What is the name of the era in which we live?
We live in the Cenozoic Era.

10. Major Geological Events Chart
Quietly complete the chart using p. 119 Monday Quiz – what to review: -Alfred Wegener’s theory (continental drift/plate tectonics theory) -North America’s Geological History **Answer questions #1-6 on p.118