1. Plates Move

2. Plates move Plates are what move They move what is on top of them
Crust is on top of the plates
Continental Crust- The crust that makes up continents/land
Oceanic Crust- The crust that makes up the oceans

3. Divergent Boundary Plates move apart Most are found in the ocean
Mid-ocean ridges are found where this happens
In the ocean they move apart and riff valleys form
This is how continents split apart
New crust is formed

4. Process 1. Hot material rises from the mantle
2. The heat causes the crust to bulge upward
3. The crust cracks, and a riff valley is formed
4. Magma rises, the continent splits apart

5. Transform Boundaries
Plates move past each other in opposite directions
Crust is not formed or destroyed
Occur mostly at the sea floor but can form on land too
San Andreas Fault

6. Convergent Boundary Plates push together 3 different types
Continental-continental collision
Oceanic-oceanic collision
Oceanic- continental collision
Crust is destroyed or folded

7. Continental- Continental Collisions
Two continental plates collide
Each plate is the same density
No plates can sink, so it has to collide
Mountains are made when the two plates run into one another
EX: Rocky Mts.

8. Oceanic- Continental Collision
A piece of oceanic crust runs into a piece of continental crust
Oceanic crust sinks
Deep-ocean trenches
Costal mountains
EX: Andes Mts.

9. Oceanic-Oceanic Collision
2 plates run into one another
The older plate will sink under the newer plate
Subduction- When one plate sinks beneath another
The plate moves into earth, and melts
Forms
Deep ocean trenches- deep canyons on the ocean floor
Island arcs- volcanic islands
EX: Hawaii

10. Hot Spot Heated rock rise in plumes, are thin columns from the mantle
The magma eventually hardens
The magma could have risen so high that it peaks out of the water
More islands will form in an arc, this shows how the plate is moving
EX: Hawaii

11. Review In what direction do plates move in convergent boundaries?
A. Towards each other
B. Away from each other
C. Depends on stress
D. Past each other

12. Review In what direction do plates move in transform boundaries
A. Towards each other
B. Away from each other
C. Depends on stress
D. Past each other

13. Review In what direction do plates move in divergent boundaries
A. Towards each other
B. Away from each other
C. Depends on stress
D. Past each other

14. Review What feature occurs at a divergent boundry A. Island arc
B. Riff valley
C. Mountains
D. surface fault

15. Review
The Andes Mountains in South America occur at what type of boundary?
A. Continent-continent convergent boundary
B. Continent-oceanic convergent boundary
C. Divergent boundary
D. Transform boundary