Download 2.1 Reinforcing Key Concepts

SECTION
EARTHQUAKES OCCUR ALONG FAULTS.
2.1 Reinforcing Key Concepts
BIG IDEA Earthquakes
KEY CONCEPT
release stress that has built up in rocks.
Earthquakes occur along faults.
faults are located along tectonic plate boundaries. The map
below shows the locations of moderate or stronger earthquakes around the world. Each black
dot represents where an earthquake has occurred. According to the map, what are three areas
in which there have been no earthquakes strong enough to be shown on the map? Why do
you think these areas have not been affected by significant earthquakes?
CHAPTER 2
Earthquakes
1. Rocks move along faults. Most
2. Faults are classified by how rocks move. A
fault forms a plane that extends
horizontally and vertically. During an earthquake, blocks of rock move along these planes.
A fault can be a normal fault, a reverse fault, or a strike-slip fault. Label each of the three
pictures below showing these three kinds of faults and describe the type of movement—
mainly vertical or horizontal—of each fault.
fault plane
direction rocks move
direction rocks move
Copyright © by McDougal Littell, a division of Houghton Mifflin Company
Earthquake
Plate boundary
Uncertain plate boundary
direction rocks move
A.
B.
C.
92 THE CHANGING EARTH, CHAPTER 2, REINFORCING KEY CONCEPTS
092-092-sean-urb-b0201-rkc 92
3/10/04, 4:19:07 PM