1. Boundary Notes EQ #1 What happens along plate boundaries?

2. Motion in the Earth https://www.youtube.com/watch?v=0 mWQs1_L3fA https://www.youtube.com/watch?v=0 mWQs1_L3fA https://www.youtube.com/watch?v=0 mWQs1_L3fA https://www.youtube.com/watch?v=0 mWQs1_L3fA

3. Plate tectonics There are 19 tectonic plates that make up earths crust (lithosphere) There are 19 tectonic plates that make up earths crust (lithosphere) The edges of these plates are identified by earthquakes, rift valleys, volcanoes and mountain ranges The edges of these plates are identified by earthquakes, rift valleys, volcanoes and mountain ranges These are called SEISMIC ACTIVITY These are called SEISMIC ACTIVITY

4. Divergent Boundaries Move apart from each other As they separate, lava flows up and forms new crust. The form ridges and Rift valleys.

5. Divergent Boundaries Ex: Mid-Atlantic ridge and Great African Rift Valley

6. Divergent Boundaries

8. Convergent Boundaries Move toward each other Features depend on types of crust colliding

9. Convergent Boundaries Oceanic - Oceanic One plate SUBDUCTS the other, forming a TRENCH Forms an ISLAND ARC OF VOLCANOES

10. Convergent Boundaries Example: Marianas Trench and Marianas Islands Might have volcanoes

11. Convergent Boundaries O - O

12. Convergent Boundaries Oceanic - Continental Oceanic plate SUBDUCTS Continental Sinking plate melts and forms VOLCANIC MOUNTAINS

13. Convergent Boundaries Example: Mt. St Helens, Andes Mountains

14. Convergent Boundaries O-C

16. Convergent Boundaries Continental - Continental NO Subduction Huge Folded mountains form

17. Convergent Boundaries Example: Himalayan Mountains

18. Convergent Boundaries C-C

20. Transform Boundaries Slide past one another. Slide past one another. Crust is fractured and many faults form. Crust is fractured and many faults form. Example : San Andreas Fault in California Example : San Andreas Fault in California

21. Transform Boundaries

22. Driving force for plate tectonics Convection Currents in the asthenosphere Convection Currents in the asthenosphere

23. Driving force for plate tectonics