1. PLATE TECTONICS

2. Plate Tectonics  Earths crust and mantle are separated into sections called plates that move  How?

3. The Layers  The crust and upper mantle  Solid, rigid, brittle  10 km thick  The lower mantle  Solid, but can flow  700 km thick LithosphereAsthenosphere

5. Lithospheric Plates  The rigid lithosphere moves around on top of the asthenosphere  The planet is divided into sections or plates (like rafts that float on the asthenosphere)

6. How do they move?  Convection cells  Utilizing the following terminology, describe how you think a convec- tion cell might work: convection cell, heat, cool, density

7. Convection Cells

8.  Convection is the transfer of heat as material circulates.  The heat causes the lower mantle to expand  The heated material rises  Runs along the lithosphere  It cools and goes back down to the core

9. How do they move?  Subduction zones  Utilizing the following terms, describe how you think subduction may work: lithospheric plates, meet, dense

10. Subduction Zone

11. Subduction Zones  Two lithospheric plates meet  The denser plate subducts underneath the less dense plate

12. Plate Boundaries  Whenever two plates meet they form boundaries