EXAM 2 – PRACTICE VERSION - KEY
GEOL 131-WINTER 2015
CHAPTER 5 – VOLCANISM
1. A magma with a high silica content and a low temperature will have a ________
viscosity.
a. High
b. Low
2. The two components of silica are
a. Silicon and iron
b. Calcium and oxygen
c. Silicon and oxygen
d. Silicon and calcium
3. Explosive eruptions are more violent than effusive eruptions because
a. Magmas associated with explosive eruptions are generated at greater depths
b. In explosive eruptions, there is more resistance to the expansion of
magma gases
c. Magmas associated with effusive eruptions are generated at greater depths
d. Magmas associated with explosive eruptions are hotter
e. Magmas associated with effusive eruptions are colder
For each of the eruptive materials below, indicate the eruptive style with which it is
associated. Mark “A” for explosive and “B” for effusive.
4.
5.
6.
7.
Blocks A
Ash
A
Low –viscosity lava B
Nuee ardente A
8. Magma chamber collapse forms which volcanic landform?
a. Composite cone
b. Cinder cone
c. Shield volcano
d. Basalt plateau
e. Caldera
Match each volcanic landform with the correct picture below.
9. Caldera
10. Composite cone
11. Shield volcano
12. Cinder cone
C
D
A
B
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C
13. Why are composite cones called composite?
a. They are made of only one type of volcanic material
b. They are made of more than one type of volcanic material
c. They are narrow and steep-sided
d. They have bases that are located below sea level
CHAPTER 6 – RUNNING WATER
14. A drainage divide is
a. The number of tributary streams in a drainage basin
b. The sum of a channel’s depth, width, and length
c. A boundary between adjacent drainage basins
d. A ridge separating first- and second-order streams within a drainage basin
15. The higher the velocity of a stream, the higher its discharge, all else being equal.
a. True
b. False
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16. What is the discharge of a stream with the following characteristics?
Channel width: 20 meters
Channel depth: 5 meters
Water velocity: 3 meters/second
a.
b.
c.
d.
300 m3/sec
28 m3/sec
12 m3/sec
33 m3/sec
32. Saltation is a rolling or sliding motion exhibited by sediment along a stream channel
bottom.
a. True
b. False
Match the meandering stream features listed below with the correct figures.
33. Oxbow lake
34. Point bar
35. Cut bank
36. Meander scar
B
D
C
A
A
Does not contain
water
B
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Contains water
C
37. Meander cutoff is a process by which
a. Oxbow lakes are created
b. Stream gradient increases
c. Meander loops are abandoned
d. All of the above
e. None of the above
38. Which of the following is a characteristic of braided streams?
a. Fine-grained sediment load
b. Deep channels
c. Variable discharge
d. Unchanging discharge
39. Which of the following is not a characteristic of braided streams?
a. Coarse-grained sediment load
b. Variable discharge
c. Typical of glaciated regions
d. Typical of tropical regions
40. Stream competence is
a. Maximum particle size a stream can carry
b. Maximum sediment volume a stream can carry
c. Maximum height a stream can reach during floods
d. Maximum velocity a stream can reach
41. Stream capacity is
a. Maximum particle size a stream can carry
b. Maximum sediment volume a stream can carry
c. Maximum height a stream can reach during floods
d. Maximum velocity a stream can reach
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42. A stream whose water has a muddy appearance probably has a high volume of
a. Bedload
b. Dissolved load
c. Suspended load
43. In a meander loop, where is the zone of maximum water velocity?
a. Around the inside of the loop
b. Around the outside of the loop
c. At the bottom of the channel
d. It varies from stream to stream
44. In order for a regional flood to occur, there must be heavy precipitation and/or higher than
normal volumes of snowmelt. There must also be
a. Saturated soils
b. Thunderstorms
c. Failed levees
d. A tsunami
CHAPTER 7 – GLACIERS
45. What is a glacier?
a. A mass of motionless ice
b. A mass of moving ice
c. An iceberg
d. A snowfield
46. Most of a glacier’s movement is accounted for by
a. Basal sliding
b. Surging
c. Melting
d. Internal flow/plastic flow
47. The ice within a glacier moves upslope when the glacier is in retreat.
a. True
b. False
48. Which of the following causes glaciers to lose mass? (Mark one answer.)
a. Calving
b. Snowfall
c. Tributary glaciers
d. All of the above cause glaciers to lose mass
Match each alpine glacial landform with the correct figure below (pictures continue on the
next page).
49. Tarn
E
50. Cirque
A
51. Hanging valley
B
52. Paternoster lakes D
53. Glacial trough
C
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54. The numerous gravel pits in southern Michigan are all mining what type of glacial
deposit?
a. Loess
b. Cirques
c. Till
d. Horns
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Match each continental glacial landform below with the correct letter on the figure below.
55. Esker
B
56. Drumlin
A
57. Moraine
D
58. Kettle
C
59. Why are variations in Earth’s orbit (eccentricity, obliquity, and precession) considered
likely causes of the “Ice Ages”?
a. They cause changes in the amount of solar energy heating the Earth
b. They cause changes in atmospheric thickness
c. They produce changes in the atomic structure of ice crystals
d. They alter Earth’s gravity, changing the likelihood that ice masses will begin
moving
60. Which of the following is an effect of the expansion of large continental ice sheets?
a. Changes in Earth’s orbital cycles
b. Depression of Earth’s crust
c. Rise in sea level
d. Rearrangement of continents
61. Pluvial lakes form during Ice Ages because
a. Climates are cooler and wetter, and lakes develop by accumulation of
rainfall
b. Glaciers fracture the Earth’s crust, allowing groundwater to seep onto the surface
c. Glacial meltwater fills in low-lying areas near the glacier
d. Ice sheets depress the crust below sea level, and ocean water floods low-lying
regions
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CHAPTER 8 – EARTHQUAKES
62. The following seismograms were taken from three stations located at different distances
from an earthquake’s epicenter. Which seismogram comes from the station located
farthest from the epicenter? C
63. How do you know your answer to the previous question is right?
a. Both wave types arrive sooner on this seismogram than on the others
b. The separation between the P and S waves is smallest on this seismogram
c. The P-waves are strongest on this seismogram
d. The S-waves are strongest on this seismogram
e. The separation between the P and S waves is largest on this seismogram
64. An earthquake occurs on the San Andreas Fault at a point 16 km below the Earth’s
surface. The city of San Jose, California is located directly above this point. The point on
the fault is the earthquake’s__________________ and San Jose is the earthquake’s
___________.
a. S-P interval; epicenter
b. Epicenter; focus
c. Focus; epicenter
d. Triangulation; seismograph
65. How do surface waves form?
a. They form when P or S-waves reach the Earth’s surface
b. They originate at the earthquake’s focus
c. They form when S-waves enter a fluid
d. They form by vibration within the mesosphere
66. Which seismic wave type always arrives second at a seismograph station?
a. P-waves
b. S-waves
c. Surface waves
d. None of the above
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67. Which of the following is not a difference between P- and S-waves?
a. Ability to propagate through a fluid
b. Velocity
c. Depth of origination
d. Vibration direction relative to direction of energy propagation
68. To determine Richter magnitude, seismologists use
a. Rock strength and S-P interval
b. Moment magnitude and rupture surface area
c. S-P interval and height of tallest peak on seismogram
d. S-P interval and rupture surface area
69. During earthquakes, witnesses have reported feeling a relatively small but noticeable
vibration under their feet, like a heavy truck passing nearby, before the main earthquake
struck. This vibration is caused by
a. P-waves
b. S-waves
c. Surface waves
d. All of the above
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