Tuesday, October 23 rd

1. Tuesday, October 23rd How do convection currents form? a. heated mantle material is less dense and rises to the top of the asthenosphere b. mantle material cools under the lithosphere, becomes more dense, and sinks c. seismic waves act like a big spoon and stir up mantle material d. both a and b are correct

2. Corny Joke of the Day What did one mountain say to the other after the earthquake? “It isn’t my fault”

3. Tier 2 PT= Tomorrow

4. Quiz Answers 10 pts Each

5. Project Grades Individual and Group

6. Welcome to Ms. Evans Cheer Camp

7. When I say transform you say Slide

8. Transform

9. Transform

10. When I say Divergent you say Apart

11. Divergent

12. Divergent

13. When I say convergent you say Collide

14. Convergent

15. Convergent

16. Review Plate Tectonics #2Convergent Boundaries

17. A convergent boundary is where two plates come together, or converge. The result of the plates hitting together is called a collision.

18. There are three combinations of how earth's crust can come together. a. Continental crust to continental b. Continental crust to oceanic c. Oceanic crust to oceanic

19. a. Continentalcrust to continentalcrust Before collision MOUNTAINS Example: India-Asia (Himalayas) After collision from: http://www.geo.lsa.umich.edu/~crlb/COURSES/270

21. Eurasian plate Indian plate Indian plate (continental crust) running into Eurasian plate (continental crust)

22. Himalaya Mountains From space

23. Even the Appalachian Mountains!

24. Folded mountains – notice the rock layers

25. b. Continental &Oceanic SUBDUCTION

26. The process by which the ocean floor sinks beneath a deep-ocean trench and back into the mantle is called Subduction

27. Why Does the Oceanic Crust sink below the Continental Crust? Oceanic crust is MORE DENSE than Continental!

28. Because one plate gets pushed under another, it is called subduction. • This is where volcanoes and trenchesform! all from: http://www.geo.lsa.umich.edu/~crlb/COURSES/270

29. Volcanoes form where a convergent boundary occurs between oceanic crust and continental crust.

30. South American plate (continental crust) running into Nazca plate (oceanic crust)

31. Andes Mts. From space View looking south – ocean to continental

33. c. Oceanic &Oceanic SUBDUCTION

35. Volcanoes also form where a convergent boundary occurs between oceanic crust and oceanic crust.

36. Aleutian islands of Alaska are volcanoes formed by oceanic crust converging with oceanic crust

37. Following volcanic islands in the Pacific Ocean can show us where oceanic crust is being subducted by oceanic crust.

38. Review Plate Tectonics #3Divergent Boundaries

39. The place where two plates move apart or diverge is called a divergent boundary.

40. #1 Sea floor spreading Can you explain this diagram!?

41. What causes sea floor spreading?

42. This is a model of sea floor spreading at a divergentboundaryis called a mid ocean ridge.

43. Oceanic crust diverging from oceanic crust

44. : www.ocean.udel.edu Did you know that the Earth’s longest mountain range is underwater and is called the mid-ocean ridge? The Mid-Ocean Ridge system, shown above snaking its way between the continents, is more than 56,000 kilometers (35,000 mi) long. It circles the earth like the stitching on a baseball!

45. Divergence can also occur in continental crust! Continental crust diverging from continental

47. African rift valley

48. Iceland’s rift valley

49. Review Plate Tectonics #4Transform Boundaries

50. Plates can also slide past each other. A transform boundary is a place where two plates slip past each other, moving in opposite directions.