Question 1

Explain what viscosity is and how it affects the effects of a volcano. Give one example to illustrate your point.

Accepted Answer

Viscosity is the resistance to flow. Hig...

Question 2

At which plate boundary is more viscous lava found?

Accepted Answer

A)   Oceanic hotspots
B)   Oceanic subduction zones
C)   Oceanic divergent plate boundaries
D)   Continental rift zones
E)   Shield volcanoes on the ocean floorF) C) and D)
G) C) and E)

Question 3

Which of following effects might an area see even if a volcano does NOT actually erupt?

Accepted Answer

A)   Lahars and pyroclastic flows
B)   Lahars and ash falls
C)   Landslides and poisonous gases
D)   Landslides and pyroclastic flows
E)   Lava flows and poisonous gasesF) B) and E)
G) B) and C)

Question 4

Which of the following is FALSE about magma?

Accepted Answer

A)   Most magmas come from melting of the asthenosphere.
B)   Some magma comes from rocks melted through decompression.
C)   Adding volatiles, such as water, to rock decreases its melting point and makes it easier to melt.
D)   Some rocks are melted from magma that is rising from deep within the Earth.
E)   Tectonic plates move around on an underground ocean of magma.F) A) and B)
G) C) and D)

Question 5

Which type of magma typically results in the greatest explosive events?

Accepted Answer

A)   Basaltic
B)   Andesitic
C)   Rhyolitic
D)   Pahoehoe
E)   AaF) A) and E)
G) C) and D)

Question 6

Volcanic ash is very lightweight and therefore is not much of a threat to buildings.

Accepted Answer

A) True 
 B)False

Question 7

What type of volcano is found in Iceland?

Accepted Answer

A)   Shield
B)   Stratovolcano
C)   Cinder cone
D)   Caldera
E)   No volcanoes are found in Iceland.F) B) and C)
G) A) and E)

Question 8

Craters differ from calderas in that craters are created from an explosion and then collapse of the volcano top whereas calderas are simply the location where lava flows originate.

Accepted Answer

A) True 
 B)False

Question 9

Do humans affect the frequency or size of volcanic eruptions?

Accepted Answer

A)   Yes. Global warming is a direct cause of many volcanic eruptions.
B)   Yes. More people living on volcanoes causes volcanoes to erupt.
C)   Yes. More people in the area of volcanoes means less groundwater in those areas and that causes volcanoes to erupt.
D)   Yes. Mitigation measures by humans keep many volcanoes from erupting.
E)   No. People do not increase or decrease the volcanic hazard.F) A) and B)
G) B) and E)

Question 10

Where is the best place to be during a pyroclastic flow?

Accepted Answer

A)   In the water
B)   In your house
C)   On a hillside
D)   In a valley
E)   Nowhere is safe during a pyroclastic flow.F) B) and D)
G) D) and E)

Question 11

Volcanic soils are usually too hot and dry to be of use for agriculture.

Accepted Answer

A) True 
 B)False

Question 12

A very large volcano with gentle slopes is a ________ , which is comprised of ________.

Accepted Answer

A)   Shield volcano...lava flows
B)   Shield volcano...pyroclastic debris
C)   Stratovolcano...lava flows
D)   Stratovolcano...lava flows and pyroclastic debris
E)   Cinder cone volcano...pyroclastic debrisF) B) and C)
G) C) and D)

Question 13

How can volcanoes contribute to climate change?

Accepted Answer

A)   Volcanoes release hot air into the atmosphere, contributing to global warming.
B)   Erupted lava from volcanoes heats up the air in the atmosphere, contributing to global warming.
C)   Lava flows cool into black rock that increase sunlight absorption by the Earth, contributing to global warming.
D)   Volcanoes can send large amounts of fine-grained ash and sulfuric acid aerosols into the atmosphere, potentially causing global cooling.E) A) and B)
F) A) and C)

Question 14

Which of the following is NOT a reason why stratovolcanoes are dangerous?

Accepted Answer

A)   They are associated with higher viscosity magma.
B)   They have dormant periods between eruptions, which can make people underestimate their hazard.
C)   They erupt abundant pyroclastic debris.
D)   They involve explosive eruptions.
E)   They erupt fast-moving lava flows that kill many people.F) D) and E)
G) A) and E)

Question 15

Because of the alert systems and people's willingness to heed warnings, no one was killed in the 1980 Mt. St. Helens eruption.

Accepted Answer

A) True 
 B)False

Question 16

Why do cinder cone volcanoes have steep slopes?

Accepted Answer

A)   They are made from lava flows that pile up steeply.
B)   They are found near other volcanoes which crowds their ability to spread out.
C)   They are made mostly from water and ash that hardens into steep cones.
D)   They are made from pyroclastic materials that pile up near where they were erupted.
E)   They are made from very thick magma that doesn't flow outward very much.F) A) and E)
G) A) and B)

Question 17

Which of the following magma types will usually flow the fastest?

Accepted Answer

A)   Basaltic
B)   Andesitic
C)   Rhyolitic
D)   All magma flows at similar speeds.E) None of the above
F) A) and B)

Question 18

The disaster at Lake Nyos in Cameroon (Africa)  is thought to have been caused by a

Accepted Answer

A)   volcanic eruption that created a giant water wave, which flooded nearby areas.
B)   volcanic eruption that created a landslide, which in turn created a giant water wave that flooded nearby areas.
C)   volcanic eruption that destroyed a dam, which flooded nearby areas.
D)   suffocating cloud of carbon dioxide gas.E) All of the above
F) None of the above

Exam 5: Volcanoes

Why do cinder cone volcanoes have steep slopes?

Correct Answer
verified

What type of volcano is found in Iceland?

Correct Answer
verified

Which of the following magma types will usually flow the fastest?

Correct Answer
verified

Which type of magma typically results in the greatest explosive events?

Correct Answer
verified

Because of the alert systems and people's willingness to heed warnings, no one was killed in the 1980 Mt. St. Helens eruption.

Correct Answer
verified

Which of following effects might an area see even if a volcano does NOT actually erupt?

Correct Answer
verified

How can volcanoes contribute to climate change?

Correct Answer
verified

A very large volcano with gentle slopes is a , which is comprised of .

Correct Answer
verified

Which of the following is FALSE about magma?

Correct Answer
verified

The disaster at Lake Nyos in Cameroon (Africa) is thought to have been caused by a

Correct Answer
verified

Where is the best place to be during a pyroclastic flow?

Correct Answer
verified

Explain what viscosity is and how it affects the effects of a volcano. Give one example to illustrate your point.

Correct Answer
verified
Viscosity is the resistance to flow. Hig...
View Answer

Volcanic soils are usually too hot and dry to be of use for agriculture.

Correct Answer
verified

Craters differ from calderas in that craters are created from an explosion and then collapse of the volcano top whereas calderas are simply the location where lava flows originate.

Correct Answer
verified

Volcanic ash is very lightweight and therefore is not much of a threat to buildings.

Correct Answer
verified

Which of the following is NOT a reason why stratovolcanoes are dangerous?

Correct Answer
verified

At which plate boundary is more viscous lava found?

Correct Answer
verified

Do humans affect the frequency or size of volcanic eruptions?

Correct Answer
verified

Exam 5: Volcanoes

Why do cinder cone volcanoes have steep slopes?

Correct AnswerverifiedShow Answer

What type of volcano is found in Iceland?

Correct AnswerverifiedShow Answer

Which of the following magma types will usually flow the fastest?

Correct AnswerverifiedShow Answer

Which type of magma typically results in the greatest explosive events?

Correct AnswerverifiedShow Answer

Because of the alert systems and people's willingness to heed warnings, no one was killed in the 1980 Mt. St. Helens eruption.

Correct AnswerverifiedShow Answer

Which of following effects might an area see even if a volcano does NOT actually erupt?

Correct AnswerverifiedShow Answer

How can volcanoes contribute to climate change?

Correct AnswerverifiedShow Answer

A very large volcano with gentle slopes is a ________ , which is comprised of ________.

Correct AnswerverifiedShow Answer

Which of the following is FALSE about magma?

Correct AnswerverifiedShow Answer

The disaster at Lake Nyos in Cameroon (Africa) is thought to have been caused by a

Correct AnswerverifiedShow Answer

Where is the best place to be during a pyroclastic flow?

Correct AnswerverifiedShow Answer

Explain what viscosity is and how it affects the effects of a volcano. Give one example to illustrate your point.

Correct AnswerverifiedViscosity is the resistance to flow. Hig...View AnswerShow Answer

Volcanic soils are usually too hot and dry to be of use for agriculture.

Correct AnswerverifiedShow Answer

Craters differ from calderas in that craters are created from an explosion and then collapse of the volcano top whereas calderas are simply the location where lava flows originate.

Correct AnswerverifiedShow Answer

Volcanic ash is very lightweight and therefore is not much of a threat to buildings.

Correct AnswerverifiedShow Answer

Which of the following is NOT a reason why stratovolcanoes are dangerous?

Correct AnswerverifiedShow Answer

At which plate boundary is more viscous lava found?

Correct AnswerverifiedShow Answer

Do humans affect the frequency or size of volcanic eruptions?

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
verified

A very large volcano with gentle slopes is a , which is comprised of .

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Viscosity is the resistance to flow. Hig...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
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