1. Plate Tectonics The theory of plate tectonics is based on the theory that plate tectonics explain the formation, movement, and subduction of Earth’s plates. Movement occurs along three type of plate boundaries. 1. Convergent boundaries 2. Divergent plate boundaries 3. Transform boundaries

2. There are about 18 plates making up our world

4. What drives the plates? Convection currents

5. Divergent Plate Boundary A place where two plates diverge, or pull apart. This happens along the mid-ocean ridge, or at a rift valley. Sea-floor spreading at the mid-ocean ridge

6. Divergent plate boundary

7. Convergent plate boundary The place where two plates come together or converge. This causes a collision. A collision may cause subduction, or mountain formation, depending on the density of the crusts colliding.

8. Convergent plate boundary

9. Transform plate boundary A place where two plates slide past each other, or move in opposite directions.

10. Transform plate boundary

11. Convergent plate boundary Divergent plate boundary