Weathering

## Multiple Choice Questions for Earthquakes - Chapter 16

Each chapter will include a few questions designed to test your knowledge of material covered in the chapter and in the Internet-based resources. Your answers are not being recorded. Try the following.

1. Which of the following describes the build up and release of stress during an earthquake?

the Modified Mercalli Scale
the elastic rebound theory
the principle of superposition
the travel time difference

2. The amount of ground displacement in a earthquake is called the _________ .

epicenter
dip
slip
focus

3. The point where movement occurred which triggered the earthquake is the _______ .

dip
epicenter
focus
strike

4. Which of the following sequences correctly lists the different arrivals from first to last?

P waves ... S waves .... Surface waves
Surface waves ... P waves .... S waves
P waves ... Surface waves ... S waves
S waves ... P waves .... Surface waves

5. How do rock particles move during the passage of a P wave through the rock?

back and forth parallel to the direction of wave travel
back and forth perpendicular to the direction of wave travel
in a rolling circular motion
the particles do not move

6. Detailed studies of what earthquake allowed researchers to develop the elastic rebound theory?.

the 1906 San Francisco earthquake
the 1964 Anchorage, Alaska earthquake
the 1755 Lisbon, Portugal earthquake
the 1985 Mexico CIty earthquake

7. How many seismograph stations are needed to locate the epicenter of an earthquake?

1
2
3
4

8. Earthquakes can occur with _________ faulting.

normal
reverse
thrust
all of these

9. Approximately what percentage of earthquakes occur at plate boundaries?

25%
50%
75%
90%

10. Which type of faulting would be least likely to occur along the mid-Atlantic ridge?

normal
reverse
transform
all of these could occur

11. How often do magnitude 8 earthquakes occur?

about 5 to 10 times per year
about once a year
about every 5 to 10 years
about every 50 to 100 years

12. The bulk modulus measures ______________.

the resistance to flow of a liquid
the resistance to change in color
the resistance to change in volume
the resistance to change in shape

13. The shear modulus measures _____________ .

the resistance to flow of a liquid
the resistance to change in shape
the resistance to change in volume of a liquid
the resistance to change in volume of a solid

14. If only density increases with increasing depth within the Earth, the velocity of a P wave should ___________ .

stay the same
increase
decrease

15. If a P wave were to go from a solid to a liquid - what would happen to its velocity?

stay the same
increase
decrease to 0.0
decrease

16. If an S wave were to go from a solid to a liquid - what would happen to its velocity?

stay the same
increase
decrease to 0.0
decrease

17. Which boundary marks a change from 100% solid to 100% liquid?

mantle ... outer core
lithosphere ... asthenosphere
crust ... mantle
none of these

18. Body waves consist of the:

P waves only
S waves only
P and S waves
Surface waves

19. With increasing travel time the difference in arrival times between the P and the S waves _________

increases
decreases
stays constant
none of the above

20. Earthquake A has a Richter magnitude of 7 as compared with earthquake B's 6. The amount of ground motion is one measure of earthquake intensity.

A is 10X more intense than B
A is 1000 more intense than B
Richter magnitude does not measure intensity
B is 0.01X as intense than A

21. In general, the most destructive earthquake waves are the __________ .

P waves
S waves
Surface waves
Q waves

22. Where is the focus with respect to the epicenter:

directly below the epicenter
directly above the epicenter
in the P wave shadow zone
in the S wave shadow zone

23. Point A, where slip initiated during the earthquake, is called the ________.

dip
epicenter
focus
scarp

24. Point B is called the earthquake ________.

dip
epicenter
focus
scarp

25. Point C is called the _________

epicenter
fault scarp
seismic wave
dip of the earthquake

26. What type of faulting is illustrated in this diagram?

normal
reverse
thrust
abnormal

27. What causes the up-and-down wiggles on the seismogram show above?

variations in air pressure
ground vibrations
tsunami waves
electromagnetic pulses

28. Which set of waves are probably the surface waves?

A
B
C
They are all surface waves

29. Which set of waves are the P waves?

A
B
C
They are all P waves

30. Which set of waves are the S waves?

A
B
C
They are all S waves

31. The difference in arrival times between which pair of waves can be used to determine the distance to the epicenter?

A and C
A and B
None of the above

32. How do rock particles move during the passage of a P wave through the rock?

back and forth parallel to the direction of wave travel
perpendicular to the direction of wave travel
in a rolling elliptical motion
in a rolling circular motion

33. How do rock particles move during the passage of a S wave through the rock?

back and forth parallel to the direction of wave travel
perpendicular to the direction of wave travel
in a rolling elliptical motion
in a rolling circular motion

34. Who developed the procedure used to measure the size of an earthquake?

Charles Richter
Edward Sheridan
James Hutton
Art Smith

35. The moment magnitude of an earthquake depends on all of the following except __.

the area of the fault break
the rigidity of the fault
the slip on the fault
the type of faulting

36. Which of the following measures an earthquake's intensity based on the observed effects on people and structures?

Richter scale
Modified Mercalli scale
the Centigrade scale
the moment magnitude scale

37. Shallow earthquakes, less than 20 km deep, are associated with _______.

convergent plate boundaries
divergent plate boundaries
transform plate boundaries
all of these

38. What type of faulting would be most likely to occur along transform faults?

normal faulting
reverse faulting
strike-slip faulting
all of these

39. What type of earthquakes would most likely occur at point A?

shallow-focus earthquakes caused by normal faulting
shallow-focus earthquakes caused by strike-slip faulting
shallow-focus earthquakes caused by thrust faulting
deep-focus earthquakes caused by thrust faulting

40. What type of earthquakes would most likely occur at point B?

shallow-focus earthquakes caused by normal faulting
shallow-focus earthquakes caused by strike-slip faulting
shallow-focus earthquakes caused by thrust faulting
deep-focus earthquakes caused by thrust faulting

41. Which of the following did not occur at a plate boundary?

New Madrid, Missouri, 1812
San Francisco, 1906
Anchorage, Alaska, 1964
Loma Prieta, California, 1989

42. Which of the following can be triggered by an earthquake?

tsunami
intense ground shaking
a landslide
all of these

43. Which of the following can trigger a tsunami?

undersea earthquakes
undersea landslides
the eruption of an oceanic volcano
all of these

44. Which of the following waves is the slowest?

P waves
S waves
Surface waves
tsunami

45. Which of the following statements is false?

Most earthquakes occur at plate boundaries
The time and location of most major earthquakes can be predicted several days in advance
Earthquakes can be caused by normal, reverse and strike-slip faulting
P waves travel faster than both S waves and Surface waves

46. Which of the following observations may indicate a forthcoming destructive earthquake?

An increase in the frequency of smaller earthquakes in the region
rapid tilting of the ground
rapid changes in water levels in wells
all of these

47. Which of the following statements best describes the state of earthquake prediction?

scientists can accurately predict the time and location of almost all earthquakes
scientists can accurately predict the time and location of about 50% of all earthquakes
scientists can accurately predict when an earthquake will occur, but not where
scientists can characterize the seismic risk of an area, but can not yet accurately predict most earthquakes

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