Deck 12: Earthquakes and Earths Interior

Question 1

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

Answer 1

E

Question 2

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

Answer 2

A

Question 3

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

Answer 3

B

Question 4

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

Question 5

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

Question 6

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

Question 7

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

Question 8

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

Question 9

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

Question 10

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

Question 11

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

Question 12

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

Question 13

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

Question 14

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

Question 15

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.

Question 16

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

Question 17

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

Question 18

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

Question 19

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

Question 20

The fault scarp in this photograph apparently formed:

A)when an earthquake rupture offset the surface
B)when the area beneath the car 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

Question 21

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

Question 22

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

Question 23

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

Question 24

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

Question 25

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

Question 26

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.

Question 27

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

Question 28

The diagram on the right 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

Question 29

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

Question 30

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.

Question 31

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

Question 32

The diagram on the right 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

Question 33

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

Question 34

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

Question 35

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

Question 36

The Modified Mercalli Intensity rating map on the right 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

Question 37

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

Question 38

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.

Question 39

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

Question 40

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

Question 41

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

Question 42

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

Question 43

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

Question 44

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

Question 45

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

Question 46

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

Question 47

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)

Question 48

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

Question 49

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

Question 50

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

Question 51

In the trench pictured to the right,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

Question 52

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

Question 53

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

Question 54

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
E)none of these

Question 55

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

Question 56

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

Question 57

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

Question 58

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

Question 59

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

Question 60

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

Question 61

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

Question 62

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

Question 63

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

Question 64

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

Question 65

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

Question 66

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.

Question 67

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

Question 68

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

Question 69

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

Question 70

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 to the right 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
E)both c and d

Question 71

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

Question 72

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)

Question 73

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

Question 74

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

Question 75

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

Question 76

In the map to the right,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

Question 77

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

Question 78

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

Question 79

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

Question 80

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