Deck 15: Geohazards: Volcanoes and Earthquakes

Question 1

Lava with high viscosity is thick and does not easily flow.

Answer 1

True

Question 2

Elastic rebound theory describes how blocks in Earth's crust bend, break, and rebound back to their original shape.

Answer 2

True

Question 3

Seismographs detect, measure, and record ground shaking from earthquakes.

Answer 3

True

Question 4

Scientists can predict the magnitude of earthquakes.

Question 5

Collapsing structures are the main threat to people created by earthquakes.

Question 6

Stratovolcanoes are the largest type of volcano.

Question 7

Worldwide, the majority of earthquakes occur in the interior of continents.

Question 8

Old buildings are retrofitted so they can better withstand shaking during an earthquake.

Question 9

Scientists can predict exactly where earthquakes will strike.

Question 10

Volcanic eruptions can sometimes be accurately predicted.

Question 11

Los Angeles has a backlog of 15,000 buildings that need retrofitting.

Question 12

Shield volcanoes are composed of mafic lava.

Question 13

Generally, flowing lava is the most serious volcanic geohazard.

Question 14

Volcanoes cool Earth's surface because their suspended aerosols reflect sunlight.

Question 15

Volcanic gases are seldom deadly.

Question 16

Felsic lava is hotter than mafic lava.

Question 17

In horst and graben topography, a horst is a valley and a graben is a ridge.

Question 18

Scientists can predict when earthquakes will strike.

Question 19

Stratovolcanoes are much larger than shield volcanoes.

Question 20

In some regions, buildings sink into the ground during earthquake shaking because of liquefaction of the sediments on which the buildings sit.

Question 21

Most tsunamis are triggered by earthquakes, but not all of them are.

Question 22

Most earthquakes occur in seismic belts.

Question 23

Horst and graben topography is formed by rotating fault blocks.

Question 24

Fragments of solid material ejected from a volcano are called pyroclasts.

Question 25

Each earthquake is assigned only one earthquake magnitude number.

Question 26

Most earthquakes are too small to be felt by people.

Question 27

The Mercalli intensity scale ranks earthquakes with seismographs.

Question 28

In the open ocean, tsunamis are difficult to detect.

Question 29

Shield volcanoes produce dangerous and explosive eruptions.

Question 30

The largest earthquake ever recorded was magnitude 9.5.

Question 31

No two earthquakes produce the same pattern of ground shaking.

Question 32

Most transform plate boundaries are on the seafloor.

Question 33

Earthquake magnitude is evaluated based on the amount of damage an earthquake causes to physical structures.

Question 34

In San Francisco, about half a million people live in buildings that need retrofitting.

Question 35

All old buildings in the U.S.have been retrofitted.

Question 36

In some regions, scientists are able to warn people of approaching seismic waves before the waves arrive.

Question 37

Tambora's climate effects included cooling summer temperatures in the northern United States by about 3°C to 6°C.

Question 38

Stratovolcanoes can produce both explosive eruptions and effusive outpourings of lava.

Question 39

Mount Fuji in Japan is a shield volcano.

Question 40

Volcanic gas is a type of pyroclast.

Question 41

Earthquakes that often come after a main earthquake are called __________.

A)foreshocks
B)seismic waves
C)aftershocks
D)seismic belts

Question 42

Tensional force occurs on __________.

A)reverse faults
B)normal faults
C)strike-slip faults
D)the focus

Question 43

Tambora's 1815 eruption is notable for what?

A)It caused the greatest known human death toll of any volcano.
B)It was the largest officially measured volcanic eruption.
C)It was the first eruption of Tambora in human history.
D)It caused 100 years of climate change.

Question 44

The 2011 Tôhoku earthquake was the fifth largest earthquake ever recorded.

Question 45

Which of the following does not control the viscosity of lava?

A)chemical composition of the lava
B)temperature of the lava
C)gas content of the lava
D)elevation at which the lava forms

Question 46

__________ is\are accumulations of lava that cover extensive geographic areas.

A)Columnar jointing
B)Flood basalts
C)A caldera
D)Large igneous province

Question 47

Which of the following is not composed of mafic lava?

A)pâhoehoe
B)'a'â
C)pillow lava
D)blocky lava

Question 48

__________ are volcanoes that form when thick lava that cannot easily flow piles up around a volcanic vent and solidifies into a mounded structure.

A)Stratovolcanoes
B)Shield volcanoes
C)Cinder cones
D)Lava domes

Question 49

The Hawaiian islands are composed of shield volcanoes.

Question 50

Yellowstone last erupted 640,000 years ago.Its VEI ranking was what?

A)5
B)6
C)7
D)8

Question 51

A rolling motion during an earthquake is made by __________.

A)P waves
B)S waves
C)R waves
D)L waves

Question 52

__________ is a pyroclast that develops a streamlined shape as it travels through the air and cools while airborne.

A)Ash
B)A block
C)Pumice
D)A bomb

Question 53

According to the figure, how many fatalities were in world's most deadly earthquake?

A)700,000
B)830,000
C)316,000
D)230,000

Question 54

A large circular depression formed at the top of a volcano by the collapse of the magma chamber is called __________.

A)columnar jointing
B)a flood basalt
C)a large igneous province
D)a caldera

Question 55

A(n) __________ volcano is one that has not erupted for over 10,000 years but could erupt again.

A)extinct
B)active
C)dormant
D)plug dome

Question 56

Earthquakes that sometimes come before a main earthquake are called __________.

A)foreshocks
B)seismic waves
C)aftershocks
D)seismic belts

Question 57

The __________ is the location where the rocks break due to stresses in the crust.

A)focus
B)seismic wave
C)epicenter
D)fault

Question 58

Which of the following types of lava did each of the Hawaiian islands first start out as?

A)pâhoehoe
B)'a'â
C)pillow lava
D)blocky lava

Question 59

__________ are large, potentially explosive, cone-shaped volcanoes composed of alternating layers of ash and lava.

A)Stratovolcanoes
B)Shield volcanoes
C)Cinder cones
D)Lava domes

Question 60

Today, about how many people live dangerously close to Mount Vesuvius?

A)10,000
B)100,000
C)300,000
D)500,000

Question 61

Most magma is about __________ percent gas by volume.

A)5
B)8
C)12
D)20

Question 62

Stored energy is released as __________ when the crust breaks.

A)electromagnetic waves
B)seismic waves
C)thermal energy
D)potential energy

Question 63

About how much more energy is released in a magnitude 4 earthquake compared to a magnitude 2 earthquake?

A)10 time more
B)30 times more
C)100 times more
D)1,000 times more

Question 64

How much more ground shaking does a magnitude 4 earthquake make compared to a magnitude 2?

A)1
B)5
C)10
D)100

Question 65

__________ is a pyroclast that is fine-grained and soft to the touch.

A)Ash
B)Lapilli
C)Pumice
D)A bomb

Question 66

__________ is a pyroclast that consists of marble- to golf ball-sized fragments.

A)Ash
B)Lapilli
C)Pumice
D)A block

Question 67

Seismic waves that travel deep through Earth's interior are called __________.

A)body waves
B)surface waves
C)compressional waves
D)shear waves

Question 68

Referring to the figure, collision zones typically have what type of faults?

A)reverse and thrust
B)normal
C)strike-slip
D)There is no one type of fault that dominates mid-ocean ridges.

Question 69

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According to the figure, how ash and rock material did the Pinatubo eruption produce?

A)< 1 cubic kilometer
B)> 1 cubic kilometer
C)> 10 cubic kilometers
D)> 100 cubic kilometers

Question 70

__________ is a pyroclast that was torn from a volcano's cone and ejected into the air.

A)A bomb
B)Lapilli
C)Pumice
D)A block

Question 71

Why do seismic waves in the western United States not travel as far as those on the East Coast?

A)because the mountains in the west help seismic waves travel
B)because the eastern United States has few earthquakes
C)because the crust in the western United States is broken and weakened by many faults
D)because the western United States is composed mainly of oceanic crust

Question 72

__________ move back and forth perpendicular to the direction the seismic waves are traveling.

A)Body waves
B)Surface waves
C)Compressional waves
D)Shear waves

Question 73

__________ produce motion that goes back and forth in a direction parallel to the direction of the traveling waves.

A)Body waves
B)Surface waves
C)Compressional waves
D)Shear waves

Question 74

The __________ usually experiences the most shaking during an earthquake.

A)focus
B)seismic wave
C)epicenter
D)fault

Question 75

Referring to the figure, the Himalayas were formed in what type of tectonic environment?

A)a subduction zone
B)a mid-ocean ridge zone
C)a collision zone
D)a transform boundary zone

Question 76

If you are on a normal fault during an earthquake, the opposite side of the fault will move __________.

A)toward you
B)away from you
C)to the left of you
D)to the right of you

Question 77

A __________ is a mudflow that forms from a volcanic eruption.

A)lahar
B)flood basalt
C)pyroclastic flow
D)lapilli

Question 78

According to the figure, subduction zones typically have what type of faults?

A)reverse and thrust
B)normal
C)strike-slip
D)There is no one type of fault that dominates subduction zones

Question 79

In 79 CE people living near Mount Vesuvius were killed by what?

A)a lahar
B)volcanic ash
C)a pyroclastic flow
D)lava

Question 80

__________ is a pyroclast that has 50% air content and floats on water.

A)Ash
B)Lapilli
C)Pumice
D)A bomb