Seismology
Geo 12
Name______________
Indicate the correct response for the multiple choice questions below. The answer may require you to
do further research.
1. When seismic waves travel through materials having different properties, their direction of travel
changes. This phenomenon is termed wave:
a) homogeneity
b) energy dissipation c) refraction
d) deflection e) density
2. Which of the following is true of P-waves?
a) travel through solids only
b) greatest velocity
d) a and c
e) b and c
c) compression/expansion waves
3. Which is true of S-waves?
a) travel through solids only
d) a and c
e) b and c
c) compression/expansion waves
b) greatest velocity
4. The velocity of seismic waves increases with:
a) decreasing distance from the earthquake
b) increasing density of the medium
c) decreasing density of the medium
d) increasing temperature of the medium
e) b and d
5. The seismic wave shadow zone refers to:
a) the transition from crust to mantle(Moho) b) the region where wither no P or no S-waves are
recorded at seismograph stations
c) the zone not facing solar radiation d) the region where no
P-waves but S-waves are recorded at seismograph stations
e) the refraction of both P and S-waves
within the Earth’s interior
6. Compare primary (P) waves and secondary (S) waves by completing the following table
Average speed
near Earth’s
surface
P-wave
S-wave
Style of movement
Medium through
which wave can
travel
Extent of shadow
zone
7. If the Earth was completely solid and had the same composition throughout:
a) how would P and S-waves behave as they travelled through Earth?
b) would either the S-wave or P-wave shadow zone exist?
Explain your reasoning.
8. Use the figure below to answer the following questions.
a) What is the speed of P-waves at a depth of 200 km?
b) What is the speed of P-waves at a depth of 2700 km?
c) Explain the reason for the differing answers for a) and b) using the terms velocity, material, depth,
and density
d) What is the speed of P-waves at a depth of 3000 km?
e) Explain the reason for the differing answers for d) and b) using the terms velocity, material, depth,
and density
9. The speed of seismic waves would be faster or slower in materials that are higher in temperature?
Explain your answer.