Download Earth`s Waters Section 1–1 Review and Reinforce (p. 17) 1

Inside Earth
Chapter 2
Earthquakes
Review and Reinforce Worksheet
Answer Keys
Section 2-1 Review and Reinforce
(p. 49)
1 a. reverse fault b. compression c. hanging wall
moves up
2 a. normal fault b. tension
c. hanging wall
moves down
3 a. strike-slip fault b. shearing
c. blocks move sideways in opposite directions
4. Any change in the volume or shape of the crust.
5. A mountain formed when normal faults uplift a block of
rock.
6. A rock fold that bends downward in the middle to form a
bowl.
7. The shaking and trembling that results from the
movement of rock along a fault beneath Earth’s surface.
8. A force that acts on rock to change its shape or volume.
9. A rock fold that bends upward into an arch.
10. A large area of flat land elevated high above sea level.
Section 2-2 Review and Reinforce (p. 53)
1. Seismic waves are vibrations that travel through Earth carrying the energy
released during an earthquake.
2. P waves travel fastest, so they would arrive first, followed by S waves, then
surface waves.
3. Surface waves
4. The moment magnitude scale provides an estimate of the total energy
released by an earthquake. It can be used to rate earthquakes of all sizes,
regardless of whether they occur close by or far away.
5. Geologists measure the difference between the arrival times of the P waves
and S waves at three or more seismographs. Using these differences, they
determine the distance of the epicenter from each seismograph and plot the
distances as circles on a map. The epicenter is located where the three circles
intersect.
6. c
7. e
8. b
9. a
10. d
Section 2-3 Review and Reinforce (p. 57)
1. Earthquakes can damage or destroy buildings, bridges, and other structures,
topple utility poles, fracture gas and water mains, and trigger
landslides, avalanches, and tsunamis.
2. Seismic waves transfer energy from hard, dense rock to loosely packed soil.
The loose soil shakes more violently than the surrounding
rock. The thicker the layer of soil, the more violent the shaking. Buildings
constructed on solid rock will shake less and suffer less damage than buildings
constructed on loose soil.
3. The buildings may have been weakened in the large earthquake and may
collapse during an aftershock.
4. When tsunamis reach the shallower water near land, their wavelength
decreases, causing their wave height to increase.
5. Drop, cover, and hold; crouch under a protective object such as a table or
desk or against an inner wall, and cover your head and neck with your arms;
avoid the outer walls, glass objects, wall hangings, and furniture that might fall
over.
6. After an earthquake, people may be injured and without water, power, and
food sources.
7. A base-isolated building; the pads or springs in the building’s foundation act
like shock absorbers, reducing the amount of energy that reaches the building
during an earthquake so it sways back and forth gently instead of shaking
violently.
8. tsunamis
9. liquefaction
10. aftershock
Section 2-4 Review and Reinforce (p. 61)
1. Fault-monitoring instruments measure changes in Earth’s crust along
faults. These changes may signal an earthquake is about to occur.
2. The locations of active faults and the locations of past earthquakes
3a. Any three: Seattle, San Francisco, Los Angeles, Salt Lake City,
Charleston, Boston
b. Phoenix, St. Louis, Atlanta
c. Any three: Denver, Minneapolis, Chicago, New Orleans, Cleveland,
New York, Philadelphia
4. Creep meter, laser-ranging device, tiltmeter, satellite
5. Creep meter: A wire stretched across a fault measures horizontal
movement of the ground.
Laser-ranging device: A laser beam bounced off the ground detects
slight fault movements.
Tiltmeter: Detects tilting of the ground along a fault by measuring the
depth of liquid in two connected bulbs.
Satellite: Bounces radio waves off the ground to detect small changes
in elevation along faults.