Practice Sheet: Plate Tectonics

PRACTICE SHEET: PLATE TECTONICS

STUDY THE LABELED PARTS OF THE DIAGRAM:

USE THE FOLLOWING TERMS FOR THE DIAGRAM ABOVE. MATCH THE TERM WITH THE LETTER. ocean floor rift valley continent mid-ocean ridge trench molten rock becomes new ocean floor convection current old ocean floor becomes molten rock volcanic mountain range

A. volcanic mountain range G. ocean floor

B. trench H. convection current

C. mid-ocean ridge I. convection current

D. rift valley J. convection current

E. continent K. molten rock becomes new ocean floor

F. ocean floor L. old ocean floor becomes molten rock

1. The plunging of the ocean crust back into the mantle is called subduction .

2. Movement of the plates across the surface of the earth is due to convection currents within the mantle.

3. A chain of volcanic islands in a curved shape is called an island arc .

4. A deep V-shaped canyon on the ocean floor is called a trench .

5. Oceanic crust is made up of basalt and is more dense than continental crust. Continental crust is made up of granite and is less dense than oceanic crust. STUDY THE DIAGRAMS BELOW. MATCH THE DESCRIPTIONS WITH THE CORRECT LETTER. LETTERS MAY BE USED MORE THAN ONCE.

A 1. two ocean plates moving apart C 8. destroying ocean floor A 2. ocean floor spreading A 9. making new ocean floor D 3. transform plate boundary C 10. Andes Mountains A 4. Mid-Atlantic Ridge B 11. Himalaya Mountains C 5. subduction of oceanic plate A 12. mid-ocean ridge B 6. two continental plates colliding C 13. trench D 7. San Andreas Fault A 14. rift valley A 15. Iceland

IN EACH SET OF TERMS BELOW, CIRCLE THE ONE THAT DOES NOT BELONG.

1. Alfred Wegener / Pangaea / Plate Tectonics / Continental Drift

2. mid-ocean ridge / Granite / Basalt / ocean-floor spreading / new ocean floor

3. old rocks / new rocks / trench / subduction

4. Mid-Atlantic Ridge / Iceland / rift valley / trench

5. Iceland / subduction / trench / Andes Mountains

6. folded mountains / volcanoes / continental plates / Himalayas

7. Hawaii / hot spot / island arc

8. trench / island arc / Hawaii / subduction / Aleutian Islands / Aleutian Trench