Download Indicate the answer choice that best completes the statement or

Name: Class: Date: Ch 9 - Plate Tectonics Review
Indicate the answer choice that best completes the statement or answers the question.
1. Seafloor spreading occurs because _____.
a. new material is being added to the asthenosphere
b. earthquakes break apart the ocean floor
c. sediments accumulate at the area of spreading
d. molten material beneath Earth's crust rises to the surface
2. While studying the ocean floor, scientists found ____ bands of magnetism.
a. plastic
b. alternating
c. no
d. rectangular
3. Active volcanoes are most likely to form at _____.
a. transform boundaries
b. divergent boundaries
c. the center of continents
d. convergent oceanic–continental boundaries
4. A fossil plant that helps support the theory of continental drift is ____.
a. Mesosaurus
b. Glossopteris
c. Glomar
d. Pangaea
5. The magnetic pattern of ocean-floor rocks on one side of an ocean ridge is ____.
a. a mirror image of that of the other side
b. younger than on the other side
c. much different from the magnetic pattern found in rocks on land
d. at right angles to the ocean ridge
6. Matching ____ on different continents are evidence for continental drift.
a. river systems
b. rock structures
c. weather patterns
d. wind systems
7. A ____ is a sensitive device used to detect magnetic fields on the seafloor.
a. seismometer
b. geologist's compass
c. Glomar
d. magnetometer
8. Folds form instead of faults where which of the following happens?
a. rocks are very hot
b. rocks are under enough pressure
c. continental plates collide
d. all of the above
9. The Great Rift Valley in Africa is a _____.
a. mid-ocean ridge
b. divergent boundary
c. convergent boundary
d. transform boundary
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Name: Class: Date: Ch 9 - Plate Tectonics Review
10. The presence of the same ____ on several continents supports the hypothesis of continental drift.
a. fossils
b. rocks
c. neither a nor b
d. both a and b
11. _____ are formed when two continental plates collide.
a. Volcanoes
b. Strike-slip faults
c. Mountain ranges
d. Rift valleys
12. The existence of coal beds in Antarctica indicates that the continent once had ____.
a. been part of Africa
b. a temperate, rainy climate
c. a cold, dry climate
d. been farther from the equator
13. The hypothesis that continents have slowly moved to their current locations is called ____.
a. continental drift
b. continental slope
c. magnetic reversal
d. convection
14. Astronauts in the distant future land on a planet that is far from Earth, hoping to build a settlement there. The
mountains in Area A are rugged. The mountains in Area B are rounded. The astronauts want to avoid any area
that might have earthquakes. Where should they settle? Why?
a. Area A, because of their mass, high rugged mountains are very stable
b. Area B, rounded mountains only exist at divergent boundaries and earthquakes only occur at convergent
boundaries.
c. Area B, rounded mountains are old and have stopped growing, indicating that the forces that caused the
mountains have become inactive.
d. Area A, rugged mountains are old and have stopped growing, indicating that the forces that caused the
mountains have become inactive.
15. What type of mountains are formed when molten rock erupts onto Earth’s surface and hardens?
a. uplifted mountains
b. fold mountains
c. volcanic mountains
d. fault-block mountains
16. Seafloor spreading occurs because ____.
a. new material is being added to the asthenosphere
b. earthquakes break apart the ocean floor
c. sediments accumulate at the area of spreading
d. molten material beneath Earth's crust rises to the surface
17. The youngest rocks on the ocean floor are located _____.
a. near continents
b. at mid-ocean ridges
c. far from mid-ocean ridges
d. near Asia
18. A lack of explanation for continental drift prevented many scientists from accepting that a single supercontinent
called ____ once existed.
a. Glomar
b. Glossopteris
c. Pangaea
d. Wegener
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Name: Class: Date: Ch 9 - Plate Tectonics Review
19. The _____ is (are) an example of a transform boundary.
a. Appalachian Mountains
b. Himalayas
c. Mid-Atlantic Ridge
d. San Andreas Fault
20. Why would the mountains shown in the diagram below stop increasing in size?
a. The two continents that collided to form them have formed a new single continent.
b. Erosion works at the exact same pace as the amount the mountains are still rising.
c. There is more action at the plate boundary than there has been previously.
d. The continental crust is too thin.
21. The Appalachian Mountains in the eastern United States are rounded and have soil where trees can grow. The
Rocky Mountains in the western United States are rugged and have much rock exposed. Which of the following
statements is true?
a. The Appalachian Mountains are younger, and have experienced more erosion.
b. The Rocky Mountains are younger, and have experienced less erosion.
c. The Appalachian Mountains are older, and have experienced less weathering.
d. The Rocky Mountains are older and have experienced more erosion.
22. Scientists have observed that the plates move at rates ranging from 1 cm to 12 cm per _____.
a. century
b. decade
c. day
d. year
23. A vast, underwater mountain chain is called a(n) _________.
a. deep-sea trench
b. oceanic crust
c. ocean ridge
d. ocean floor sediment
24. Bands of rock on the seafloor showing alternating magnetic orientation indicate Earth's magnetic field has ____.
a. reversed itself in the past
b. weakened
c. become stronger
d. remained the same
25. The youngest part of the ocean floor is found ____.
a. along deep sea trenches
b. where ocean sediments are thickest
c. near ocean ridges
d. where Earth’s magnetic field changes polarity
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Name: Class: Date: Ch 9 - Plate Tectonics Review
26. The youngest rocks on the ocean floor are located ____.
a. near continents
b. at mid-ocean ridges
c. far from mid-ocean ridges
d. near Asia
27. The alignment of iron minerals in rocks when they are formed reflects the fact that Earth's ____ has reversed
itself several times in the past.
a. magnetic field
b. core
c. asthenosphere
d. gravity
28. Continental drift was not widely accepted when it was first proposed because ____.
a. Wegener couldn’t explain why or how the continents moved
b. continental landmasses were too big to move slowly over Earth’s surface
c. magnetic and sonar data proved that Wegener’s hypothesis was incorrect
d. mantle convection currents weren’t in motion at that time
29. Fault-block mountains occur where _____.
a. compression squeezes the crust
b. tension pulls the crust apart
c. tension squeezes the crust
d. compression pulls the crust apart
30. ____ is a fossil fern that helped support Wegener’s hypothesis of continental drift.
a. Gondwanaland
b. Kannemeyerid
c. Mesosaurus
d. Glossopteris
31. Plates move apart at _____ boundaries.
a. convergent
b. stable
c. divergent
d. transform
32. A _____ forms where two oceanic plates collide.
a. hot spot
b. subduction zone
c. transform boundary
d. rift valley
33. Many early mapmakers thought Earth’s continents had moved based on ____.
a. plate boundary locations
b. fossil evidence
c. climatic data
d. matching coastlines
34. Wegener believed that the continents were assembled as part of a supercontinent about ____ years ago.
a. 250 million
b. 300 million
c. 400 million
d. 500 million
35. Continental drift states that continents have moved ____ to their current location.
a. vertically
b. slowly
c. quickly
d. very little
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Name: Class: Date: Ch 9 - Plate Tectonics Review
Answer Key
1. d
2. b
3. d
4. b
5. a
6. b
7. d
8. d
9. b
10. d
11. c
12. b
13. a
14. c
15. c
16. d
17. b
18. c
19. d
20. a
21. b
22. d
23. c
24. a
25. c
26. b
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Name: Class: Date: Ch 9 - Plate Tectonics Review
27. a
28. a
29. b
30. d
31. c
32. b
33. d
34. a
35. b
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