Ch.12 Earthquakes And Earth'S Interior Complete Test Bank

Exploring Geology, 5e (Reynolds)

Chapter 12 Earthquakes and Earth's Interior

1) The December 26, 2004 Indonesian earthquake occurred

A) on land.

B) from a large volcanic eruption.

C) from subduction of the Indian-Australian plate.

D) along the San Andreas fault.

2) Which area did NOT have casualties caused by the Indonesian earthquake of 2004?

A) Indonesia

B) India and Sri Lanka

C) Islands in the Indian Ocean

D) The eastern coast of Africa

E) All of these areas had casualties.

3) What was the main cause of death associated with the 2004 Indonesian earthquake?

A) poor construction of buildings

B) ground shaking that caused the soil to turn to a liquid

C) a large ocean wave or tsunami

D) massive fires along the coast

4) Which of the following types of faults does NOT generate earthquakes?

A) Normal fault

B) Reverse fault

C) Thrust fault

D) Strike-slip fault

E) All types of faults can generate earthquakes.

5) What do the two stars near the center of this block represent?

A) the location of the earthquake

B) the star at depth is the place where the earthquake is generated

C) the star at depth is the hypocenter

D) the star on the surface is the epicenter

E) All of these choices are correct.

6) An earthquake generated on this type of fault would most likely be associated with a

A) subduction zone.

B) divergent plate boundary.

C) rift.

D) caldera.

E) transform boundary.

7) What is true about the earthquakes on this figure (at points A and B)?

A) For each earthquake, the epicenter and hypocenter are located close together.

B) Neither earthquake is related to the volcano.

C) An eruption makes loud noises but not seismic waves.

D) Landslides cause death but not seismic waves.

8) The earthquake location shown as the red dot is generated on what type of fault?

A) Reverse fault

B) Normal fault

C) Thrust fault

D) Strike-slip fault

9) Which of the following is NOT a way that volcanoes and magma can cause earthquakes?

A) Volcanic explosions cause seismic waves.

B) Volcanoes can load the crust, causing faulting and earthquakes.

C) Many volcanoes have steep, unstable slopes that can cause landslides that shake the ground.

D) Moving magma within or below the volcano can cause earthquakes.

E) All of these are ways that volcanoes can cause earthquakes.

10) In what order will the seismic stations (#1 and #2) detect seismic waves generated by the earthquake shown in the image?

A) Station 1 will detect them first, followed by Station 2.

B) Station 2 will detect them first, followed by Station 1.

C) Stations 1 and 2 will detect the waves at the same time.

D) Only station 2 will detect waves because Station 1 is too close to the hypocenter.

11) Most earthquakes occur at depths of

A) less than 100 km.

B) greater than 100 km.

C) 100-700 km.

12) Earthquakes in subduction zones generally only occur at depths of

A) up to 700 km.

B) greater than 700 km.

C) 700-1000 km.

13) Which of the following may create earthquakes?

A) movement along faults

B) volcanic eruptions and magma movement

C) landslides

D) explosions and human activity

E) All these may create earthquakes.

14) As it grows, a fault rupture that began at depth

A) has an oval shape below the surface.

B) stops growing once any part of the rupture reaches the surface.

C) will grow until the seismic waves reach the surface.

D) will grow until it reaches the mantle.

15) When do rocks along a fault have the highest amount of stress and stored elastic strain?

A) right before an earthquake

B) right after an earthquake

C) several weeks or months after an earthquake

D) None of these because rocks cannot behave in an elastic manner.

16) The fault scarp in this photograph apparently formed

A) when an earthquake rupture offset the surface.

B) when the area beneath the scarp was dropped down relative to the area to the left.

C) more than 50 million years ago.

D) when material on the left was compacted.

E) All of these choices are correct.

17) What is illustrated by this figure?

A) Stress consistently increases through time.

B) Stress consistently decreases through time.

C) As stress increases, the fault strength increases.

D) Stress increases until it matches the strength of the fault, and then stress decreases.

18) Which of the following may indicate the presence of a fault scarp?

A) Break in a slope along a hill side

B) A "step" in the landscape

C) Freshly exposed, generally linear feature with little/no vegetation

D) All of these can indicate the presence of a fault scarp.

19) The image shows a surface expression of slip along a normal fault caused by an earthquake. What is the indicated feature?

A) Fault scarp

B) Hanging wall

C) Graben

D) Hypocenter

20) On this map of southeastern Asia and adjacent areas, which site would have earthquakes along a mid-ocean ridge?

A) 1, In the Indian Ocean

B) 2, In Tibet

C) 3, Near Japan

D) 4, Near the Tonga island arc

21) On this map of southeastern Asia and adjacent areas, which site would have earthquakes along a continental collision?

A) 1, In the Indian Ocean

B) 2, In Tibet

C) 3, Near Japan

D) 4, Near the Tonga island arc

22) On this map of southeastern Asia and adjacent areas, which site would have earthquakes along a subduction zone?

A) 1, In the Indian Ocean

B) 2, In Tibet

C) 3, Near Japan

D) 4, Near the Tonga island arc

E) 3 and 4

23) On this map of earthquakes near Japan, why do shallow earthquakes occur to the east and deeper earthquakes occur to the west?

A) The continental crust is thicker to the east.

B) The crust is hotter near Japan, closer to the volcanoes.

C) There is a continental collision to the east.

D) The subduction zone dips to the west.

24) On this map of South America and adjacent areas, which site would have earthquakes along a subduction zone?

A) 1, The oceanic trench

B) 2, Below the magmatic belt

C) 3, Along a passive margin

D) 4, In the middle of the Atlantic Ocean

E) Both 1 and 2

25) On this map of South America and adjacent areas, which site would have earthquakes related to plate divergence?

A) 1, The oceanic trench

B) 2, Below the magmatic belt

C) 3, Along a passive margin

D) 4, In the middle of the Atlantic Ocean

E) Both 1 and 2

26) On this map of South America and adjacent areas, which site would have the deepest earthquakes?

A) 1, The oceanic trench

B) 2, Below the magmatic belt

C) 3, Along a passive margin

D) 4, In the middle of the Atlantic Ocean

E) Both 1 and 2

27) If an area has shallow, intermediate, and deep earthquakes, what can you infer about the area?

A) It is near a subduction zone.

B) The shallow earthquakes will be closer to the trench than deeper ones.

C) The depth pattern of earthquakes can be used to determine which way the slab is inclined.

D) This area has the potential for large earthquakes.

E) All of these choices are correct.

28) Which of the following is true about where earthquakes occur?

A) Earthquakes are randomly distributed across most of Earth.

B) Earthquakes mostly occur away from plate boundaries.

C) Deep and intermediate-depth earthquakes occur near subduction zones.

D) Deep earthquakes are most common near rising mantle plumes.

29) Most earthquakes occur along

A) plate boundaries.

B) continental margins.

C) major rivers.

D) lines parallel with Earth's magnetic field.

30) The continental block shown in this figure has a transform boundary, a reverse fault, and a continental rift. What type of activity could cause an earthquake here?

A) Strike-slip faulting

B) Normal faulting

C) Reverse faulting

D) Movement of magma near the rift

E) All of these choices are correct.

31) Where do most earthquakes occur near mid-ocean ridges?

A) at great depths (more than 100 km)

B) along the axis of the ridge and on transform faults that connect ridge segments

C) in the asthenosphere where mantle undergoes decompression melting

D) on the boundary between the mantle and the oceanic crust

E) All of these choices are correct.

32) Most large earthquakes on subduction zones occur because of

A) warming of cold oceanic crust.

B) melting of cold oceanic crust.

C) melting of the mantle.

D) energy released in erupting volcanoes.

E) faulting along the plate boundary.

33) Which of the following is a major source of earthquakes associated with continental collisions?

A) thrust faults

B) slip along the plate boundary

C) faulting in a wide area adjacent to the collision zone

D) All of these choices are correct.

34) In which of the following ways may earthquakes be generated within a continental plate?

A) intrusions of magma

B) continental rifting and normal faulting

C) transform faults

D) movement of preexisting faults subjected to new stress

E) All of these choices are correct.

35) Which of the following is a characteristic of P-waves?

A) They compress and then expand the rock in the direction the wave travels.

B) They are generated near the surface and only compress the rock as they travel.

C) They travel slower than other seismic waves.

D) They displace the rock back and forth in a direction that is perpendicular to their travel direction.

E) They cannot be recorded on seismographs.

36) This diagram indicates that

A) S-waves are the first wave to arrive at station and then die out into P-waves.

B) S-waves are the last wave to arrive at the station.

C) P-waves arrive first, followed by S-waves.

D) surface waves arrive first, followed by S-waves and then P-waves.

E) surface waves cause the smallest vibrations.

37) What is NOT true about seismic waves?

A) Most seismic waves can be described as a series of repeating crests and troughs.

B) The material within the wave moves long distances along with the wave.

C) Some seismic waves travel on the surface and are called surface waves.

D) Some surface waves shuffle material side to side while others move material up and down.

E) Some seismic waves travel through the interior of Earth.

38) Which of the following is a characteristic of S-waves?

A) They cannot travel through liquids.

B) They shear rock from side to side or up and down.

C) They displace the rock in a direction that is perpendicular to their travel direction.

D) All of these choices are correct.

39) How would this diagram change if the seismic station was farther from the earthquake?

A) The P-waves would arrive later.

B) The S-waves would arrive later.

C) There would be a larger gap between the arrives of the P- and S-waves.

D) All of these choices are correct.

40) The time it takes for a complete wave to pass, is the

A) wave amplitude.

B) period.

C) wave height.

41) On this time-travel curve, if a large earthquake is 400 km away from the station, what can you say about the arrivals of the P- and S-waves?

A) The P-waves will arrive 40 seconds before the S-waves.

B) The P-waves will arrive 400 seconds before the S-waves.

C) No S-waves will arrive at this distance from the earthquake.

D) None of these choices are correct.

42) Using this nomogram, what is the magnitude of an earthquake that is 500 km from a seismic station and has an amplitude of 0.2 mm?

A) 2.0

B) 4.0

C) 6.0

D) 7.0

E) 10.2

43) The diagram below shows the record of one earthquake on seismograms at three different stations in a seismic network. These three seismograms show:

A) ISCO station is closest to the earthquake.

B) WUAZ station was right at the earthquake.

C) DUG station is farthest from the earthquake.

D) WUAZ is the closest station, followed by DUG, and then ISCO.

E) None of these choices are correct.

44) The diagram below shows data from a single earthquake plotted on a diagram that shows the mathematical relationship between distance, magnitude, and S-wave amplitude. What do these data show?

A) The distance between stations WUAZ and DUG is 680 km.

B) Station ISCO is 22 km from the earthquake epicenter.

C) The local magnitude of the earthquake recorded by these three stations is 4.1 MI.

D) Station DUG was closest to the earthquake.

45) The Modified Mercalli Intensity rating map below shows intensity values that range from more than X to less than III. What does this map show?

A) This earthquake had a Richter magnitude of 10 or 11 near the source.

B) This earthquake had a Richter magnitude of 3 or 6 along the East Coast.

C) The earthquake was not felt in southern Florida.

D) Shaking was felt only very near to the earthquake.

E) Building damage occurred in all of the zones that are shaded on this map.

46) How do we determine the location of a recent earthquake?

A) Measure the amplitude of surface waves in a single station.

B) Point video cameras at the landscape to record which way the surface moves.

C) Use seismic records from three or more stations.

D) Read old newspaper accounts of how the land moved.

E) None of these choices are correct.

47) Based on the three seismograms, which seismic station was closest to the epicenter of the earthquake?

A) ISCO

B) DUG

C) WUAZ

D) All stations were the same distance from the earthquake.

48) If three seismic stations have the following P–S intervals: DUG = 57 sec, WUAZ = 73 sec, ISCO = 14 sec, what is the order from closest station to the earthquake to the one farthest away?

A) ISCO-DUG-WUAZ

B) DUG-ISCO-WUAZ

C) WUAZ-DUG ISCO

D) ISCO-WUAZ-DUG

49) Which are true of "Richter" or "Local" magnitude calculations?

A) use maximum S-wave amplitude on a seismogram

B) use a nomograph to relate distance, magnitude, and amplitude

C) most commonly used

D) All of these are true.

50) Shaking during an earthquake can

A) liquefy unconsolidated sediments, causing destruction of buildings on top of them.

B) generate a tsunami.

C) trigger landslides.

D) cause rigid buildings to collapse.

E) All of these choices are correct.

51) Which of the following would NOT be a good idea in an area that has a high risk for earthquakes?

A) Have many new buildings be made of rigid concrete or masonry.

B) Keep 72 hours worth of food and water in an easily-carried backpack.

C) Have hospitals install computerized earthquake warning systems that will shut down natural gas systems and turn on back-up generators.

D) Require that new buildings be built to flex easily.

E) All of these would be a good idea.

52) Which of the following can cause extensive damage well after the ground shaking associated with an earthquake stops?

A) tsunami

B) fire

C) flooding from subsidence or failure of dams

D) All of these choices are correct.

53) Which of the following are potential sources of destruction that may be caused either directly or secondarily by earthquakes?

A) Landslides and rock falls

B) Tsunami

C) Aftershocks

D) Fires

E) All of these choices are correct.

54) Most deaths from earthquakes are caused by

A) collapse of structures.

B) flooding of coastal areas.

C) landslides.

D) fires due to ruptured natural gas lines.

55) The huge 1964 Alaskan earthquake, one of the largest earthquakes ever recorded, was caused by

A) rupture on a long segment of a strike-slip fault.

B) normal faulting on an ancient fault zone in the crust.

C) thrusting along a subduction zone (megathrust).

D) an underwater landslide that caused a tsunami.

E) a volcanic eruption on Augustine volcano.

56) What likely caused much of the damage shown in this photograph in the 1906 San Francisco earthquake?

A) a breakdown in the computerized warning system

B) a tsunami

C) fires that broke out after the earthquake

D) ground ruptures, cracks, and fissures

57) Which of the following places did NOT experience a major earthquake?

A) Northridge area of Los Angeles

B) Mexico City

C) Charleston, South Carolina

D) New Madrid, Missouri

E) All of these experienced major earthquakes.

58) Which of the following did NOT cause damage in the 1906 San Francisco earthquake?

A) ground shaking

B) a tsunami

C) fires that broke out after the earthquake

D) ground ruptures, cracks, and fissures

59) The shaded areas on this map have significant earthquake risks because

A) the area is near an active plate boundary.

B) the area is over a subduction zone.

C) there are many active strike-slip faults.

D) stress generated on far-off plate boundaries can reactivate ancient faults.

60) The image indicates that

A) two major zones exist for earthquake risk in the eastern United States.

B) the risk for earthquakes in extreme southeast Missouri is very low.

C) the eastern United States is under no risk for earthquakes.

D) Florida has the highest risk for earthquakes along the east coast.

61) The highest death tolls from earthquakes are generally due to

A) people living in areas with high risks for earthquakes.

B) high population densities.

C) substandard construction practices.

D) All of these choices are correct.

62) Which of the following resulted from the large 2011 Tohuku earthquake in Japan?

A) severe ground shaking that damaged buildings near the earthquake

B) a deadly tsunami

C) destruction of a nuclear power plant

D) All of these choices are correct.

63) What is the tectonic setting of the large 2011 Tohuku earthquake in Japan?

A) slip along a transform fault that cuts through Japan

B) slip along a transform fault that is just offshore to the north

C) rifting in the Sea of Japan, west of the island

D) slip along a subduction zone (megathrust)

64) Most deaths from the 2010 earthquake in Haiti were due to

A) a large tsunami that swept into the island from the north.

B) a large tsunami that swept into the island from the south.

C) a large landslide that buried the capital city.

D) collapse of buildings.

E) All of these choices are correct.

65) Why did the Christchurch earthquake (2011) in New Zealand cause much more damage than the larger Canterbury earthquake (2010)?

A) It was larger in magnitude and was deeper.

B) It was closer to a large city with buildings that had been damaged by the earlier earthquake.

C) A large landslide from the Southern Alps mountain range buried the capital city.

D) All of these choices are correct.

66) What are some of the reasons major recent earthquakes have had large death tolls?

A) structural collapse of poorly built structures

B) generation of damaging tsunami

C) location near high population densities

D) All of these choices are correct.

67) Sudden movement on a fault can cause a tsunami when

A) a hurricane or cyclone is occurring.

B) the fault suddenly uplifts or downdrops the seafloor.

C) hot water trapped below the seafloor is released.

D) a fault on land has a large displacement.

E) None of these choices are correct.

68) Landslides and volcanic eruptions can cause a tsunami by

A) causing ground shaking.

B) causing large winds and fast-moving pyroclastic flows.

C) causing a large mass of rock to catastrophically displace the water.

D) forming large gas bubbles under water.

E) heating up the water, causing it to expand.

69) Which of the following cannot cause a tsunami?

A) Faulting

B) An underwater landslide

C) A volcanic eruption

D) A strike-slip fault on land

E) All of these can cause a tsunami.

70) Which of the following is true about tsunamis?

A) In deep water they are slow enough that a boat can outrun them.

B) They form a high wall of water when still in deep water.

C) A tsunami can flood areas that are several kilometers inland.

D) All of these choices are correct.

E) None of these choices are correct.

71) In order to provide an early warning system, which of the following is LEAST helpful in trying to predict a tsunami?

A) world-wide seismic networks that broadcast warnings based on an earthquake's potential for generating a tsunami

B) deploying warning buoys to detect small changes in sea level

C) monitoring earthquakes on land

D) considering the tectonic setting and type of plate boundary that is nearby

72) On this map of South America and adjacent areas, which site would most likely generate a tsunami?

A) 1, The oceanic trench

B) 2, Below the magmatic belt

C) 3, Along a passive margin

D) 4, In the middle of the Atlantic Ocean

73) Earthquakes, landslides, and volcanic eruptions that occur beneath the sea may generate a large sea wave called a

A) tsunami.

B) tide.

C) P-wave.

D) rogue wave.

74) Tsunami may be generated by

A) earthquakes that cause the seafloor to shift.

B) landslides that displace large amounts of water.

C) activity associated with volcanic eruptions.

D) All of these may generate a tsunami.

75) Which feature might indicate that this area has relatively recent earthquakes?

A) a change in topography across the structure

B) the presence of a fault scarp

C) the bends in streams

D) the steam channels on the right side that no longer continue onto the left side

E) All of these choices are correct.

76) In the trench pictured below, the information most important to a geologist studying a prehistoric earthquake is

A) there are layers of sediment and soil.

B) the sediment is light colored.

C) there is a vertical crack in the trench wall.

D) the layers have been offset a measurable distance across a crack.

77) What types of information can be gained from trenches dug across a fault?

A) the offset of layers of sediment and soil

B) samples of charcoal to date by carbon-14

C) layers of carbon-rich peat, which can be dated by carbon-14

D) All of these choices are correct.

78) What feature suggests that this is a strike-slip fault rather than some other kind of fault?

A) the presence of a fault scarp

B) the soft appearance of the landscape

C) the horizontal offset of the drainage channel

D) differences in vegetation across the fault

E) the lack of human development

79) Prehistoric earthquakes may be studied by

A) digging trenches along a fault in order to map the offset of layers of sediment and soil to provide a timeline for interpreting when the fault moved.

B) using seismic recording stations to gather data about P-waves, S-waves, and surface waves so that earthquake magnitude can be determined.

C) looking at seismograms in order to measure P–S time to determine the epicenter of the earthquake.

D) using satellite data to create an interferogram and show how Earth deformed near the fault rupture.

80) Why is it important to study prehistoric earthquakes?

A) To determine the recurrence intervals and likely size of earthquakes to help people in a region plan for future seismic events.

B) There are no modern earthquakes to study, so prehistoric earthquakes are the only ones that may provide data to scientists.

C) They provide the most accurate data from seismometers and therefore the best seismographs.

D) Modern earthquakes are all much smaller than prehistoric earthquakes and cannot provide details about larger seismic events.

81) In the map below, areas of significant earthquake risk are shaded. Most high risk areas will be located

A) next to the oceans.

B) in mountainous areas.

C) near a boundary between tectonic plates.

D) near volcanoes.

E) in the center of continents.

82) Six large historical earthquakes occurred on the Parkfield segment of the San Andreas fault prior to 2004, with the last one of these occurring in 1966. The graph below plots the actual versus predicted dates of all the earthquakes on the Parkfield segment and shows

A) all the earthquakes before 1966 occurred exactly when predicted.

B) the 2004 earthquake occurred earlier than predicted.

C) the 2004 earthquake occurred later than predicted.

D) graphs like this are a precise way to predict earthquakes.

83) The top cross section below shows earthquakes along the San Andreas fault before October 17, 1989 and the one on the bottom shows earthquakes along the same fault after that date. These two cross sections illustrate that

A) one way to predict the locations of future earthquakes is to identify seismic gaps.

B) San Francisco is due for an earthquake.

C) the most dangerous part of a fault may be one that has not had recent earthquakes.

D) All of these choices are correct.

84) Short-term earthquake prediction

A) is complex, but techniques are still developing that hold promise.

B) relies entirely on historical records of earthquakes.

C) accurately pinpoints when an earthquake event will occur.

D) is reliable enough to enable evacuation of cities prior to large earthquakes.

85) Long-range earthquake forecasting

A) is based mainly on the knowledge of when and where earthquakes occurred in the past.

B) uses tectonic settings and historical records.

C) measures patterns of seismic activity along a fault to determine locations and recurrence intervals.

D) All of these choices are correct.

86) Why does the United States have such varying risks of seismic activity?

A) Some areas are near plate boundaries, while others are not.

B) Some regions in the continental interior have active fault systems.

C) Volcanic activity can cause seismic risk in some areas.

D) These are all reasons the United States has varying risks of seismic activity.

87) Which of the following is NOT true about some segments of the San Andreas fault?

A) Much of the northern San Andreas fault moved during the 1906 San Francisco earthquake.

B) Some segments of the fault creep slowly rather than storing up large amounts of energy.

C) Some segments of the fault produce moderate-sized earthquakes every couple of decades.

D) The fault has strike-slip motion, so the area west of the fault could fall into the sea.

E) One part of the fault has not moved for more than 100 years.

88) The southern San Andreas fault near Los Angeles is considered a candidate for a major earthquake because

A) it moved fairly recently during the Northridge earthquake and so is ready to move again.

B) it is a divergent plate boundary.

C) magma is rising along the fault and heating it up.

D) this segment of the fault has not moved for more than 100 years.

89) What features may be common along active faults, like the San Andreas?

A) Offset stream channel

B) Scarp

C) Linear ridge and/or valley

D) Drainage channels run parallel to fault

E) All of these are common features.

90) What features in the image help you identify the location of the fault?

A) Stream channel runs parallel with faults

B) Linear ridges and valley

C) Scarp

D) All of these choices are correct.

91) Which observations would tell you the most about the geometry of rock layers deep in the subsurface?

A) the mine shaft into granite (1)

B) a seismic reflection survey (2)

C) a shallow drill hole (3)

D) a magnetic survey (4)

E) gravity survey (5)

92) What location on the surface would provide easily gathered information about what is below the surface, without using expensive machines?

A) mine dump at A

B) mine dump at A and rocky hill at B

C) rocky hill at B and stream channel at C

D) mine dump at A and stream channel at C

E) None of these choices are correct.

93) The density profile across a buried streambed suggests that

A) materials in the streambed are less dense than underlying materials.

B) the uppermost layer in the streambed has the lowest density.

C) the channel has a steep side and a gentle side.

D) All of these choices are correct.

94) A seismic wave is refracted to a steeper angle when it

A) passes from a slower material into a faster one.

B) passes from a faster material into a slower one.

C) keeps going at the same speed but is getting deeper.

D) passes from a solid to a liquid.

95) What is one way that we determine the depth to the base of the crust?

A) drilling very deep wells along the San Andreas fault

B) observing the deeper parts of underground mines

C) observing whether seismic waves that travel through the crust arrived after those that traveled through the mantle

D) using P- and S-waves to locate boundaries between molten and solid rock

E) None of these choices are correct.

96) The refracted wave shown in the diagram has passed into a material that caused it to

A) slow down.

B) speed up.

C) travel the same speed but rise toward the surface.

D) rise toward the source of the earthquake.

97) Which of the following does NOT help explain why refraction causes some seismic waves to return toward Earth's surface?

A) Steeply descending rays get refracted to shallower angles as they encounter faster materials at depth.

B) Rising rays refract upward as they encounter slower and slower material.

C) The seismic waves encounter materials with different properties, including density.

D) Steeply descending rays encounter the liquid core and reflect back to the surface.

98) The cause of the P-wave shadow zone includes

A) P-waves are converted to S-waves, which cannot travel through the core.

B) some P-waves are refracted upward before they reach this zone.

C) some P-waves are refracted inward into the core, through which they cannot travel.

D) the P-waves travel curved paths and are prevented from reaching the core-mantle boundary.

E) All of these choices are correct.

99) The image, indicating the path of a seismic wave through a segment of the Earth, shows

A) refraction causes seismic waves to take curved paths through Earth.

B) seismic waves are refracted to shallower and shallower angles at depth.

C) waves are eventually bent back toward the surface.

D) The image shows all of these.

100) Based on the image, which of the following is true?

A) Since the seismic rays are straight, we can determine that the physical properties of the material do not change.

B) Since the seismic rays are straight, we can determine that the material is causing the seismic wave to slow at depth.

C) Since the seismic rays are straight, we can determine that the material is causing the seismic wave to speed up at depth.

D) The seismic wave is being refracted and reflected as it travels through the material in the image.

101) When a seismic wave hits an interface and some of the energy is sent back toward the surface, that wave is said to have been

A) reflected.

B) refracted.

C) deflected.

D) defracted.

102) When a seismic wave hits an interface and some of the energy is bent as it crosses that boundary, the wave has been

A) refracted.

B) reflected.

C) defracted.

D) deflected.

103) What is true of reflection versus refraction?

A) Both may happen to a seismic wave as it encounters boundaries between materials of different physical properties.

B) Reflection sends a portion of the wave energy back away from the encountered boundary.

C) Refraction bends a portion of the wave energy as the wave either slows or speeds up as it crosses the encountered boundary.

D) All of these are true.

104) Which factors influence the velocity of P-waves as they travel through the Earth?

A) How rigid the material is

B) The density of the material

C) How easily the rocks are compressed

D) All these factors influence the velocity of P-waves.

105) Overall, a P-wave increases in velocity with depth. This implies that

A) rocks are increasing in density with depth.

B) rocks are decreasing in density with depth.

C) rocks do not change density with depth.

D) the P-waves travel curved paths and are prevented from reaching the core-mantle boundary.

E) P-waves cannot travel through molten material.

106) How does the seismic tomography method work?

A) Large pieces of rock are put inside a medical device and x-rayed to see what is inside.

B) Large pieces of rock are put inside a medical device and subjected to seismic waves.

C) Some seismic waves coming from different directions arrive faster or slower than expected.

D) Seismic instruments are set up on different sides of a small hill to measure the elevation.

107) This model of flow within Earth predicts that

A) subducted plates pile up on the core-mantle boundary.

B) material rises near the core-mantle boundary.

C) cold material is more dense and sinks.

D) hot material is less dense and rises.

E) All of these choices are correct.

108) Geologists can investigate the interior of the Earth by

A) examining rocks that once resided at great depths.

B) subjecting rocks to high temperature and pressure in laboratory settings.

C) creating computer and numerical models to model processes that occur at depth.

D) All of these are ways geologists can investigate the interior of the Earth.

109) Geologists look at rocks that were once at great depth, create high temperature and pressure conditions for rocks in the laboratory, and develop computer models in order to

A) investigate deep conditions and processes within the Earth.

B) determine how sedimentary processes work at the surface.

C) predict patterns for stream channels cutting through loose sediment.

D) show how volcanic ash will behave in the atmosphere.

110) Seismic tomography has aided with which of the following regarding the interior of the Earth?

A) The existence of the D'' layer along the core-mantle boundary

B) Modeling areas of hot plumes and cool subducted slabs

C) Creation of flow models of the mantle

D) All of these choices are correct.

111) This photograph from the 1964 Alaskan earthquake shows a white area of seafloor that was uplifted during the event. What does this observation specifically suggest about how the earthquake might cause damage?

A) Areas on land could be affected by liquefaction.

B) Areas on land could experience landslides.

C) This earthquake could have caused a tsunami because it offset the seafloor.

D) The earthquake could have caused fires because it released sulfur-dioxide gas.

112) Which of the following was NOT associated with the Alaskan earthquake of 1964?

A) destruction of houses when a layer of weak clay liquefied

B) landslides generated from steep mountainsides

C) sinking of some downtown buildings by several meters

D) a tsunami that killed people in Oregon and California

E) a large strike-slip fault

113) What did geologists discover from studying the aftermath of the 1964 Alaskan earthquake?

A) Some parts of the coastline were uplifted and others subsided.

B) Changes in elevation were not systematic, occurring randomly over the area.

C) There was no good explanation for large waves that resulted from the earthquake.

D) Fissuring of the ground and ice was limited to an area very near the epicenter.

114) The image is a similar cross-section to the one developed by a USGS geologist after the large 1964 Alaska earthquake, showing how uplift from the earthquake was explained by thrusting of the continent over the oceanic crust. How did this support the development of the theory of plate tectonics?

A) The motion indicated is the same as an ocean-continent convergent plate boundary with subduction, as is predicted for this area by plate tectonics.

B) The motion indicated is similar to what would be predicted by a divergent plate boundary in plate tectonics.

C) The USGS explanation from 1964 was so completely wrong that scientists knew they needed to develop a new theory to explain crustal motion.

D) The motion is transform plate boundary motion, which is the main type of boundary plate tectonics dictates for the southern coast of Alaska.

115) Which of the following features was most likely the cause of the earthquake in the Investigation?

A) oceanic trench

B) collapse of hills along the shoreline

C) faulting along a line of cliffs

D) a landslide off Red Mesa

E) earthquakes from within Lava Mountain

116) What type of evidence was used in the Investigation to locate where the earthquake occurred?

A) photographs showing the amount of damage in different places

B) newspaper accounts of where buildings were destroyed

C) newspaper accounts recording eyewitness observations

D) seismograms from three stations

E) All of these choices are correct.

117) If an earthquake occurred near the oceanic trench in this figure, which one of the following hazards is likely to threaten the town of Mesaview?

A) ground shaking

B) liquefaction of soils and other weak materials because of shaking

C) landslides and other slope failures caused by shaking

D) destruction by a tsunami

118) If an earthquake occurred near the oceanic trench in this figure, which one of the following hazards is likely to threaten the town of Ashton?

A) destruction by a tsunami

B) liquefaction of soils and other weak materials because of shaking

C) landslides and other slope failures caused by shaking

D) All of these choices are correct.

119) If an earthquake occurred near the oceanic trench in this figure, which one of the following hazards is likely to threaten the town of White Sands?

A) landslides and other slope failures caused by shaking

B) destruction by a tsunami

C) volcanic material erupted from lava mountain

D) All of these threaten the town of White Sands.