2. Structure of the Earth Crust = solid outermost layer Mantle = middle layer Core = inner layer outer core = liquid inner core = solid

3. Why do we have continental drift? Internal Heat Drives Geological Activity Convection: hot rock rises, cool rock falls.

4. Why do we have continental drift? Earth has molten center Convection current form in mantle The crust moves with these currents Internal Heat Drives Geological Activity Convection: hot rock rises, cool rock falls & the solid surface of the Earth moves

5. Surface of Earth Divided into Pieces called "Plates"

6. Figure 1-21 Surface of Earth Divided into Pieces called "Plates"

7. Most Volcanoes form at plate boundaries

8. Most Earthquakes occur at plate boundaries

9. Types of Plate Boundaries Transform boundaries Figure 1-30

10. Transform boundary Example: San Andreas Fault in CA

11. Transform boundary Example: San Andreas Fault in CA

12. Types of Plate Boundaries Divergent boundaries Figure 1-25

13. Types of Plate Boundaries Divergent boundaries Example: Mid ocean ridge

14. Types of Plate Boundaries Continental collision Figure 1-27 Convergent boundaries continental collision

15. Types of Plate Boundaries Subduction Convergent boundaries

16. Hawaii = Hot spot

17. What kind of plate boundaries are there off Washington’s coast?

18. Cascadia subduction zone in side view http://en.wikipedia.org/wiki/Image:Subduction.jpg

19. http://www.nps.gov/archive/olym/geology/accretion.htm