1. Plate Tectonics
SPI Recognize that lithospheric plates continually move at rates of centimeters per year.
SPI Describe the relationship between plate movements and earthquakes, mountain building, volcanoes, and sea floor spreading.

2. Introductory Video Clip-
-Plate Tectonics Introduction UJI

3. Academic Vocabulary Pangaea - theory that “all land” was once joined.
Continental Drift - idea that land masses move apart over time.
Seafloor Spreading – continents are moving apart at a rate of 1cm per year.
Convergent Boundary - boundary where two plates collide.
Divergent Boundary - boundary where two plates move away from each other
Transform Boundary - boundary where plates slide past one another
Harry Hess – known for the idea of seafloor spreading
Alfred Wegner – developed the theory of Pangaea

4. 3 Plate Boundaries Convergent Boundary-where two plates COLLIDE.
Divergent Boundary-where two plates move apart…DIVIDE.
Transform Boundary-where two plates SLIDE against each other.

5. Convergent Boundary = Collide
Mountain ranges often form where tectonic plates push against each other.

6. Convergent = Subduction Zone
A subduction zone is where one tectonic plate sinks under the other. Hint…the prefix “sub” means under

7. Video Clip - Convergent Boundary

8. Divergent Boundary = Divide

9. Divergent = “Seafloor spreading”
Harry Hess—
This theory put forth by Harry Hess says that there are cracks in the sea floor and the two plates are actually being pulled apart…Dividing. Is this plate movement convergent or divergent??? 9

10. Video Clip - Divergent Boundary

11. Continental Drift 1cm per year. Why?
The theory of continental drift says that the continents have slowly moved apart.
1cm per year. Why?
“Pangaea” - Alfred Wegner’s proposed theory that all land was joined together in the past.
Pangaea = “all land”

12. Transform Boundary= Slide
Where two plates slide past each other, earthquakes are known to occur.

13. Transform Boundary - Transform Boundary

14. Earth’s Plate Boundaries
What do you think all the dark black lines represent?

15. Video Clip- Layers of the Earth Rap

16. Bell Ringer #1
Scientists theorize that the Atlantic Ocean is slowly increasing in width. Which is the best approximation of the rate at which lithospheric plates beneath the Atlantic Ocean are moving?
a. 2 millimeters per year
b. 2 meters per year
c. 2 centimeters per year
d. 2 kilometers per year

17. Bell Ringer #2
The Andes Mountains of South America were gradually formed when the Nazca and South American tectonic plates collided. Which of these caused this collision?
a. convection currents in Earth’s mantle
b. volcanic activity in Earth’s crust
c. movement of material within Earth’s core
d. changes in Earth’s magnetic field

18. Fossil Clues???
How do fossil clues support Wegner’s idea of Pangaea? Where??