1. Theory of Plate Tectonics Theory that pieces of lithosphere move around on top of the asthenosphere

2. Plate Boundaries The edges of different pieces of The lithosphere meet at lines called plate boundaries

3. Plate Boundaries Plate Videos

4. So the plates move. Now What? As the plates move, they produce changes in Earth’s surface, including volcanoes, earthquakes, mountain ranges, and deep- ocean trenches.

5. 3 Types of Plate Boundaries Divergent Convergent Transform Divergent Transform

6. 3 Types of Boundaries Divergent boundary= two plates move apart Magma rises and creates new crust or seafloor Causes: mid- ocean ridges, rift valleys, new crust, volcanoes

7. Divergent Boundaries © All Rights Reserved. Diverging Africa

8. Diverging Iceland

9. 3 Types of Boundaries Convergent= when two tectonic plates push into one another.

10. Convergent Boundaries Continental vs. Continental Continental vs. Oceanic Oceanic vs. Oceanic

11. Continental vs. Continental When two continental crustal plates collide, the continents buckle upward and form mountains. Himalayas- Asia

13. Oceanic vs. Continental The oceanic plate slides under the continental plate. The continental crust crumbles and forms new mountains.

14. Oceanic vs. Continental Ex: Andes mtn in S. America Cascade Mtns. in N. America- Mt. St. HelensMt. St. Helens

15. Oceanic vs. Oceanic Two oceanic plates collide, one of the oceanic plates slides under the other. oceanic plates slides also called a subduction zone subduction zone

16. Hawaiian Islands Oceanic vs. Oceanic

17. Transform boundary When two tectonic plates slide past each other horizontally Produces? Earthquakes

18. San Andreas Fault

19. New Madrid Fault

20. How do the plates move? CONVECTION CURRENTS Hot material rises while cooler material near the surface sinks Convection example

21. How do the plates move? CONVECTION CURRENTS Hot material from deep within the Earth rises while cooler material near the surface sinks

23. Convection currents

24. How do we know? Sea-floor spreading =new ocean floor is created as two lithospheric plates pull away from one another.

25. Seafloor spreading

26. The Plates Move… So what now? Which way? 50 million years