Plate Tectonics Notes SheetName:
Directions: answer the following questions.
1. What is plate tectonics?
2. Identify the 4 plates that are moving apart (use page 480).
a.b.
3. Identify 4 plates moving together or colliding (use page 480).
a.b.
4. Identify 2 plates that are sliding past each other (use page 480).
a.b.
5. Name the layers of the Earth’s crust..
6. What is the lithosphere?
7. How are the composition and density of continental crust different than the rest of the lithosphere?
8. Where is the asthenosphere?
9. What is the major property of the asthenosphere?
10. How do the lithospheric plates move where convection currents are rising?
11. How do the lithospheric plates move where convection currents are sinking?
12. What is the theory of continental drift?
13. List 3 pieces of evidence that Alfred Wegener used to support the theory of continental drift.
a.
b.
c.
14. Why do earthquakes and volcanoes occur at plate boundaries?
15. Where is the largest belt of active earthquakes and volcanoes located?
16. Name 3 volcanoes that occur in this belt.
a.
b.
c.
17. Describe Earth’s magnetic polarity when the magnetic poles are reversed.
18. What is the pattern of polarity reversals at spreading plate boundaries.
19. Describe the age of rocks of the ocean floor relative to spreading plate boundaries.
20. What are spreading centers?
21. What occurs at spreading centers?
22. What is heat flow?
23. What is the relationship between heat flow and distance from spreading center?
24. How are the plates moving at a mid-ocean ridge?
25. What 2 features occur at mid-ocean ridges?
a.
b
26. Name and locate 2 mid-ocean ridges.
a.
b.
27. How are the plates moving at a transform boundary?
28. Give an example of a transform boundary.
29. What is a converging boundary?
30. What surface feature occurs at converging boundaries?
31. What is happening to the plates at a subduction zone?
32. What is a divergent boundary?
33. What features are characteristic of the collision of an oceanic plate and a continental plate?
34. Give an example of 2 oceanic plates colliding.
35. How are subduction boundaries related to mid-ocean ridges?
36. List 3 kinds of material that can become part of a continent.
a.
b.
c.
Answers:
1. study of the formation & movement of lithospheric plates
2. a. North American & Eurasian, b. South American & African
3. a. Indian & Eurasian, b. South American & Nazca
4. North American & Pacific
5. consists of crust & upper mantle
6. it is rigid & approx. 100 km thick
7. made of granite, rather than basalt, it is less dense
8. below the lithosphere
9. able to flow
10. they move apart
11. they move together
12. a large continent made from Africa & S. A. broke & moved apart
13. a. shape of coastline, b. fossils, c. distinctive rocks
14. plate movements cause stress
15. around the Pacific Ocean
16. a. Mt. St. Helens – Washington, b. Fujiyama – Japan, c. Pinatubo – Philippines
17. present north becomes South and South becomes North
18. they are in bands parallel to & on opposite sides of plate boundaries
19. they’re older further away from the boundary
20. area between spreading plate boundaries
21. new rocks form and pushes away older rocks
22. the measure of the amount of heat leaving rocks of the lithosphere
23. highest at center, decreases in temp. away from center
24. they are moving apart
25. a. rift valley, b. fracture zones
26. a. Mid-Atlantic Ridge - between N.A. & Eurasian plates; S.A. & African plates, b. East Pacific Rise - between Pacific & N.A. plates
27. they slide past each other
28. San Andreas Faults
29. 2 plates colliding
30. mountains
31. one plate is pulling down under another plate
32. where 2 plates are moving apart
33. trenches & mountain chains
34. fast-moving Pacific Plate against the slower moving Philippine Plate
35. the subduction plate is pulled further down than at other plate boundaries
36. lithosphere forms at ridges & disappears at trenches in subduction zones
37. a. deep-sea sediment, b. volcanic rock, c. continental sediments