1. Theory of Plate Tectonics

2. What Wegner knew… Continents fit together like a puzzle
Similar fossils found on different continents
A continent has gone through climate changes due to its location on Earth
Similar rock formations on different continents

3. What Wegner Couldn’t Prove…
Cause or force that moved massive continents apart and together
Areas where new crust was formed and old crust destroyed
Edges of Plates  Where are they?

4. Objectives
Identify and explain the force that drives plate motion…and pretty much everything else in the universe
Describe the 3 different types of plate boundaries AND the landforms associated with each
Describe seafloor spreading
Know the special case of hot spots

5. Review from Yesterday

6. What are 5 layers of the Earth?
Inner Core
Outer Core
Mantle
Asthenosphere
Lithosphere

7. What are the two types of crust (lithosphere)?
Continental Crust
Oceanic Crust

8. The Driving Force
Demo

10. Why does anything hot Rise?
Molecules or materials become LESS dense when they are hotter. Why?
Higher Temperatures  More energy of Molecules  Molecules are spread out = LOWER DENSITY
Vice Versa
Lower density materials float on higher density materials = warmer materials will ALWAYS float on cooler materials

11. What is Convection?
Transfer of Heat Energy from Hot  Cold when materials are in contact with each other
Cool Magma Sink
Cooled Magma
Reheats
Hot Magma Rises
Earth’s Core

13. 3 - Types Plate Boundaries
Convergent = Collision of Plates
Divergent = Plates Moving Apart
Transform = Plates Slipping Past Each Other

14. Convergent Boundary

15. 2 Effects of Convergent Boundaries
Mountain Building
A) Oceanic to Oceanic Crust Collision
B) Continental to Continental Crust Collision
Subduction Zone with Volcanic Mountain Chains
Oceanic to Continental Crust Collision
*Crust is being destroyed at convergent boundaries*

17. Subduction Zone

18. Divergent Boundary Sea Floor Spreading

19. Divergent Boundary Rift Valley

20. 2 Outcomes of Divergent Boundary
Sea-Floor Spreading/Mid-Ocean Ridges
Crust is being Formed
Rift Valleys
Depression or Gap in Crust is Formed

23. Transform Boundary

25. Outcomes of Transform Boundaries
Crust is not being destroyed or created
Crust is being deformed  metamorphic rock
No Associated Landforms

27. Case of Seafloor Spreading
Rocks Closest to Ridge is youngest; vice versa

28. Case of Hawaii
Hot Spots = where magma bubbles up forming volcanoes

29. Earthquake and Volcano Pattern

30. Evidence for Plate Tectonics
Continents fit together like a Puzzle
Similar Fossils on different continents
A continent may have gone through several climates due to its changing position on surface
Similar Rock formations on different climates
Seafloor Spreading/Mid-Ocean Ridges/Subduction Zones
Plate Boundaries  Earthquake and Volcano Patterns
Heat generated inside drives Convection Current

31. In Review Plates Move due to Convection Landforms Mountains Trenches
Mid-Ocean Ridges
Rift Valleys
Volcanoes
3 types of boundaries
Earth’s Crust gets recycled
Earthquakes
Hot Spots

32. At this point… Evidence used for Continental Drift and Plate Tectonics
Structure of Earth
Continental vs Oceanic Crust
How Convection Works
Why Convection Works Like It Does
Describe the 3 types of plate boundaries
Landforms associated with each boundary