1. I. Theory 9.2 Plate Tectonics  A) Surface of Earth is broken into 20 plates (LITHOSPHERIC PLATES) Lithosphere Asthenosphere 1) Lithosphere riding on top of the Asthenosphere

2. B) A tectonic or lithospheric plate is one of numerous rigid sections of the lithosphere that move as a unit over the material of the asthenosphere.

3. 9.2 Plate Tectonics  A) Divergent boundaries (also called spreading centers)  2 plates move apart.  B) Convergent boundaries  2 plates move together.  C) Transform fault boundaries margins where 2 plates grind past each other w/out the creating or destroying the lithosphere. II. Plate Boundaries