1. Plate Tectonics
Geography of Canada

2. Ice Age – Scrat’s Continental Crack Up

3. Pangaea = Supercontinent

6. Alfred Wegener
In 1915, Alfred Wegener, a German scientist, suggested the theory of Continental Drift (moving of the continents)
Although Wegener was somewhat correct, he was unable to explain “HOW” the continents were moving. In other words, what was the driving force behind the movement of the continents?

7. Wegener’s Points of Proof
He saw the jigsaw fit between South America and Africa
He found fossils of the same plants and animals on separate continents (Africa and S. America)
He found mountains of similar age and structure on both sides of the Atlantic Ocean
He found evidence of ice sheets once covering parts of Africa, India, Australia and S. America

8. Continental Drift

9. Today ………..

10. Alfred Wegener’s Idea of Continental Drift

11. Tectonic Plates Today
Major plates today…. around 13

12. Convection Currents The Atlantic Ocean getting bigger
The plates are pulled apart by convection currents in the mantle below
Caused by heat released from natural radioactive processes
At the mid-Atlantic ridge molten rock from below rises up to fill the gap with new igneous rock
It’s like dumping a box of Kraft Dinner into a pot of boiling water on the stove…
Plate Tectonics and Convention Currents

16. So the Earth must be growing?
Dense heavy oceanic crust is subducted below less denser continental crust.
The friction melts rock
This magma rises through the crust to form new volcanoes
This is happening in South America (The Andes)

17. Continents Collide
Eventually when plates move together the continental crust collides
The heat and pressure make metamorphic rock
It also pushes and folds the rocks into high mountains
The Himalayas rise to 8848m and are still growing today

18. Processes Where Plates Meet

19. When Plates Separate Divergence
2 or more plates are pulling away from each other (new crust is created)
Ex) Mid Atlantic Ridge

20. Divergence

21. When Plates Collide Convergence
-1 plate dives under the other (Subduction)
- Crust is destroyed and recycled back into the interior of the earth
- Mountain creation and volcanoes
Convergent Boundaries

22. Convergence

23. When Plates Slide Transform
2 plates are sliding horizontally past each other
Ex) The San Andreas Fault, California
(1300 km long)
Associated with Earthquakes

24. Transform Faults

25. Earthquakes

26. Earthquakes – mainly along plate boundaries

27. Earthquakes in Canada?!

28. Using your text books…. Read pages 114-116
Make sure you take a look at the visuals of Wegener’s Points of Proof (Fig. 11-5)
When you’re finished, use Fig (pg. 116) to complete the tectonic plates map provided by your teacher