Name _______________________________Class __________________ Date __________________
Direct Reading 10.2
Section: The Theory of Plate Tectonics
Fill in the blank. (The answer is in the FISRT paragraph) Page 267
1. ______________ is the theory that explains why continents move.
HOW CONTINENTS MOVE
In the space provided, write the letter of the definition that best matches the term or phrase.
____ 2.oceanic crust(p.267)
_3.continental crust(p.267)
____ 4.tectonic plates(p.267)
______ 5.
lithosphere(p.267)
____ 6.asthenosphere(P.267)
a. the solid outer layer of Earth, which consists of the crust and the rigid
upper part of the mantle
b. dense crust made of rock that is rich in iron and magnesium
c. blocks of Earth’s shell that ride on a deformable layer of the mantle
d. solid, plastic layer of the mantle beneath the lithosphere
e. low-density crust made of silica-rich rock
TECTONIC PLATES
Word Bank: 15, earthquake, two or more plates
7. Scientists have identified __________major tectonic plates and many smaller plates. (Page 268)
8. A sudden movement along the boundary of a tectonic plate is a(n)________________. (Page 268)
9. Frequent earthquakes in a given zone are evidence that________________ may meet in that area. (Page 268)
TYPES OF PLATE BOUNDARIES
DRAW A LINE TO MATCH THE WORD WITH THE BOUNDARY PICTURE
10. DIVERGENT(P. 269)
11. CONVERGENT (P.270)
12. TRANSFORM (P. 271)
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Plate Tectonics
Name _______________________________Class __________________ Date __________________
Match In the space provided, write the letter of the definition that best matches the term
or phrase.
___ 13.mid-ocean ridg(p.269)
___ 14.subduction zone(p.270)
______15. fracture zone(p.271)
b. region where one plate moves under another
d. undersea mountain range
e. short segments of a mid-ocean ridge that are connected by transform
boundaries
Word Bank: rift valley, sinks, volcanic mountain
16. A narrow valley that forms where the plates separate at a divergent boundary is called a _________.(p.269)
17. When oceanic lithosphere collides with continental lithosphere, the oceanic lithosphere is less dense than
the continental lithosphere, so it subducts, or __________.(p. 270)
18. The magma rises to the surface and forms a_____________.(p. 270)
CAUSES OF PLATE MOTION
______19. The movement of heated material due to differences in density is called (p.272)
a. convection.
c. radioactivity.
c. plate motion.
______20. Earth’s mantle is heated by energy generated by (p.272)
a. Earth’s core and radioactivity.
b. boiling water.
c. cool, dense mantle material.
______21. What causes tectonic plate movement? (p.272)
a. Lack of a convection cell causes plates to rise.
b. As the mantle material moves, the overlying tectonic plates move along with it.
c. Divergent boundaries come together.
WRITE THE CORRECT ANSWERS
22. What three mechanisms of Earth’s convecting system work together to cause plate motions? (P.274)
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Original content Copyright © Holt McDougal. All rights reserved. Additions and changes to the original content are the responsibility of the instructor.
Holt McDougal Earth Science
14
Plate Tectonics