Geology 110: Earth and Space Science
Chapter 5 (Earthquakes) Homework
SELF-REFLECTION AND COMPREHENSION SURVEYS
Checkpoint 5.1, p. 109
#1: The map shows the locations of 15 of the world’s largest urban areas. Compare it
with a map of plate boundaries from Chapter 4. On the basis of their locations relative to
plate boundaries, which six cities are most likely to experience an earthquake?
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Your list of six cities:
Checkpoint 5.2, p. 109
#2: Using the map in Checkpoint 5.1, which of the groups of cities below are most likely to
experience subduction zone earthquakes?
a) Istanbul, Los Angeles, Sydney
c) Beijing, Tokyo, Calcutta
b) New York, Rio de Janeiro, Buenos Aires
d) Jakarta, Mexico City, Lima
Checkpoint 5.3, p. 109
#3: The discovery of the potential for mega-earthquakes on the Cascadia subduction zone is an
example of how scientific explanations are developed. Briefly explain how the development of
this hypothesis illustrated the following characteristics of scientific explanations.
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1. It was provisional (tentative).
2. It was based on observations.
3. It was predictable and testable.
4. It offered natural causes for natural events.
Checkpoint 5.5, p. 111
#4: An earthquake occurred on the Erie fault 5 kilometers (3 miles) beneath San Gabriel.
Damage from the earthquake was greatest in nearby Fremont. The farthest report of
shaking was recorded in Stockton. Where was the earthquake’s epicenter?
a. The Erie Fault b. San Gabriel c. Fremont d. Stockton
Checkpoint 5.6, p. 112
#5: Examine the following images.
Photo (a) was taken following the Izmit earthquake in Turkey in 1999. On the basis of
your observation of the picture, locate the approximate position of the fault (draw the
position on the photograph) and classify the fault type. Cite the reasons, data and
inferences supporting your answer.
Photo (b) was taken in the Grand Teton mountain range of northwestern Wyoming.
Which location represents a fault scarp in the picture? a) 1 b) 2 c) 3 d) 4
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Checkpoint 5.9, p. 119
#6:
Examine the following cutaway view of a section of Earth’s crust containing a fault.
Answer the questions that follow, assuming that an earthquake originated at the focus
shown on the fault surface.
Which location represents the epicenter of this earthquake?
a) A and B only
b) C and D only
c) E only
locations
d) none of these
Which location(s) would experience both body waves and surface waves?
a) A and B only b) C and D only
c) E only
d) A,B,C,D and E
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Checkpoint 5.10, p. 120
#7: Examine the following seismogram, which shows a 26-minute-long record of the
seismic waves from the 1906 San Francisco earthquake as received by a seismograph
station in Germany, over 14,000 kilometers (8,700 miles) away. Then answer the
questions that follow.
Which letter represents the arrival of the first S waves?
a) a
b) b
c) c
d) d
e) e
f) f
Approximately how much time elapsed between the arrival of the first P and S waves?
a) 60 seconds
b) 4 minutes
c) 10 minutes
d) 60 minutes
See section 5.5 for question below:
#8:How much would ground motion (amplitude) increase between magnitude 4.5 and 5.5
earthquakes?
a) No increase
c) 10 times as much
b) 5 times as much
d) 30 times as much
Checkpoint 5.12, page 121
#9: Place the numbers corresponding to the following phrases in the appropriate locations
in the seismic wave Venn diagram provided (please reproduce diagram from page 121):
1. Most damaging
7. Second arrival
2. First arrival
8. Love wave
3. Last arrival
9. 2-3 km/s in crust
4. Body waves
10. In Earth’s interior
5. Rayleigh wave
11. On Earth’s surface
6. 4-6 km/s in crust
12. Determines magnitude
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Checkpoint 5.14, p. 124
#10: Three sites (L1, L2, L3) record earthquake magnitude and earthquake intensity for
the same earthquake. L1 is located closest to the focus and L3 is farthest away. Where is
the intensity greatest and what happens to the earthquake magnitude calculated at the
different sites?
a) Intensity is greatest at L1; calculated magnitude is the same at each site.
b) Intensity is greatest at L3; calculated magnitude is the same for each site.
c) Intensity is greatest at L1; calculated magnitude decreases with distance from the
focus.
d) Intensity is greatest at L3; calculated magnitude decreases with distance from the
focus.
Checkpoint 5.18, page 129
#11: Imagine that two inland cities of the same population experience two identical
earthquakes (same magnitude, same focal depth, and same location relative to city). One
city is devastated; the other suffers only light damage. Using only information from this
section of the chapter, suggest two contrasting scenarios to explain why one city might be
heavily damaged while the other escapes relatively unharmed.
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