Question 1

Which of the following events would you NOT expect from the gigantic Toba ash- flow eruption?

Accepted Answer

A)  Worldwide drop in human populations. 
B)  Burial of Asia under a thick blanket of ash. 
C)  Worldwide rise in sea level. 
D)  Initiation of a six- year- long global "volcanic winter." 
A)  Worldwide drop in human populations. 
B)  Burial of Asia under a thick blanket of ash. 
C)  Worldwide rise in sea level. 
D)  Initiation of a six- year- long global "volcanic winter." C

Question 2

Discuss two of the secondary environmental effects associated with volcanic eruptions.

Accepted Answer

There are two main secondary environmental effects associated with volcanic eruptions. The first involves the emission of sulfur dioxide from the volcano. Atmospheric moisture combines with the sulfur to form sulfuric acid, which in turn produces acid precipitation. The second effect involves volcanic gas and ash that are spewed into the atmosphere. Gases and particles are often emitted in sufficient quantities to reduce the amount of sunlight reaching the Earth for four or more years following the eruption. This effect results in cooler temperatures and a shortening of the warmer seasons.

Question 3

Describe the differences in the volcanic products of basaltic and rhyolitic volcanoes.

Accepted Answer

Basaltic volcanoes often produce nonviolent pahoehoe and 'a'a lava flows, columnar jointing, lava tubes, and pillow structures. Rhyolitic volcanoes produce explosive expulsions of pyroclastics such as volcanic blocks and other tephra, rapid flows of hot gas and ash (nue´e ardentes), and volcanic mudflows (lahars).

Question 4

If a volcano has not erupted in the past few thousand years, but is likely to erupt sometime in the future, it is considered to be:

Accepted Answer

A)  active. 
B)  extinct. 
C)  dormant. 
D)  none of the above. 
A)  active. 
B)  extinct. 
C)  dormant. 
D)  none of the above.

Question 5

Discuss why efforts to predict volcanic eruptions sometimes fail.

Accepted Answer

Methods for predicting eruptions are fai

Question 6

What is the most common way of predicting volcanic eruptions?

Accepted Answer

A)  Abnormal animal behavior. 
B)  Harmonic tremors. 
C)  Drop in sea level. 
D)  Water wells suddenly dry up. 
A)  Abnormal animal behavior. 
B)  Harmonic tremors. 
C)  Drop in sea level. 
D)  Water wells suddenly dry up.

Question 7

Why is the Olympus Mons volcano on Mars so much larger than similar shield volcanoes on Earth?

Accepted Answer

Evidence indicates that Earth's shield v

Question 8

Compared to rhyolitic lavas, basaltic lavas tend to be:

Accepted Answer

A)  higher in viscosity and retain dissolved gases. 
B)  higher in viscosity but easily release dissolved gases. 
C)  lower in viscosity and easily release dissolved gases. 
D)  lower in viscosity and retain dissolved gases. 
A)  higher in viscosity and retain dissolved gases. 
B)  higher in viscosity but easily release dissolved gases. 
C)  lower in viscosity and easily release dissolved gases. 
D)  lower in viscosity and retain dissolved gases.

Question 9

Which of the following statements regarding volcanoes is NOT true?

Accepted Answer

A)  Basaltic volcanoes have more gentle slopes than rhyolitic volcanoes. 
B)  Violent volcanoes tend to occur at convergent plate boundaries, whereas gentle volcanoes tend to occur at divergent plate boundaries. 
C)  Rhyolitic volcanoes usually form calderas, while basaltic volcanoes form shield cones. 
D)  Magma of gentle volcanoes has a higher silica content and a higher viscosity than magma of violent volcanoes. 
A)  Basaltic volcanoes have more gentle slopes than rhyolitic volcanoes. 
B)  Violent volcanoes tend to occur at convergent plate boundaries, whereas gentle volcanoes tend to occur at divergent plate boundaries. 
C)  Rhyolitic volcanoes usually form calderas, while basaltic volcanoes form shield cones. 
D)  Magma of gentle volcanoes has a higher silica content and a higher viscosity than magma of violent volcanoes.

Question 10

All of the following are likely environmental effects of a volcanic explosion EXCEPT:

Accepted Answer

A)  acid precipitation. 
B)  decreased global temperatures. 
C)  decreased sunlight. 
D)  an increased growing season. 
A)  acid precipitation. 
B)  decreased global temperatures. 
C)  decreased sunlight. 
D)  an increased growing season.

Question 11

Of the following, the magma with the highest viscosity would have:

Accepted Answer

A)  a high silica content and low temperature. 
B)  a high silica content and high temperature. 
C)  a low silica content and high temperature. 
D)  a low silica content and low temperature. 
A)  a high silica content and low temperature. 
B)  a high silica content and high temperature. 
C)  a low silica content and high temperature. 
D)  a low silica content and low temperature.

Question 12

Whether they are basaltic or rhyolitic, almost all volcanoes have both:

Accepted Answer

A)  volcanic domes and calderas. 
B)  volcanic cones and craters. 
C)  lava flows and ash flows. 
D)  pahoehoe and aa flows. 
A)  volcanic domes and calderas. 
B)  volcanic cones and craters. 
C)  lava flows and ash flows. 
D)  pahoehoe and aa flows.

Question 13

Explain why felsic magmas have a higher viscosity and retain gases more than mafic magmas.

Accepted Answer

Higher viscosity occurs in felsic magmas

Question 14

All of the following events could indicate an impending eruption EXCEPT:

Accepted Answer

A)  a highly eroded, volcanic peak. 
B)  discovery of new hot springs around the volcano. 
C)  swarms of small earthquakes in the region. 
D)  a measurable bulge or swelling of the volcano. 
A)  a highly eroded, volcanic peak. 
B)  discovery of new hot springs around the volcano. 
C)  swarms of small earthquakes in the region. 
D)  a measurable bulge or swelling of the volcano.

Question 15

Which of the following is a likely product of a subaqueous basaltic eruption?

Accepted Answer

A)  'A'a. 
B)  Pillow structures. 
C)  Pumice. 
D)  Pahoehoe. 
A)  'A'a. 
B)  Pillow structures. 
C)  Pumice. 
D)  Pahoehoe.

Question 16

Which of the following characteristics would you NOT expect from an effusive eruption?

Accepted Answer

A)  Central vent and fissures are the lava source. 
B)  Flows of basaltic lava. 
C)  Quiet, nonexplosive eruption event. 
D)  Large volumes of pyroclastic materials produced. 
A)  Central vent and fissures are the lava source. 
B)  Flows of basaltic lava. 
C)  Quiet, nonexplosive eruption event. 
D)  Large volumes of pyroclastic materials produced.

Question 17

What are ash- flow eruptions?

Accepted Answer

Ash- flow eruptions are pyroclastic erup

Question 18

How did the cataclysmic eruption of Krakatau in 1883 affect global climate?

Accepted Answer

The eruption produced a black cloud of d

Question 19

Volcanoes are beneficial to humanity in many ways. All of the following are benefits EXCEPT:

Accepted Answer

A)  volcanoes give scientists insight into subterranean rock composition. 
B)  some gases released by volcanoes are toxic to humans. 
C)  many volcanic soils prove fertile for agriculture. 
D)  some volcanoes provide sources of clean energy. 
A)  volcanoes give scientists insight into subterranean rock composition. 
B)  some gases released by volcanoes are toxic to humans. 
C)  many volcanic soils prove fertile for agriculture. 
D)  some volcanoes provide sources of clean energy.

Question 20

A welded tuff forms when:

Accepted Answer

A)  hot lava flows over rocks, causing them to become metamorphic. 
B)  semi- molten volcanic bombs fuse together. 
C)  particles within a lahar cool and crystallize. 
D)  particles within a nue´e ardente cool and crystallize. 
A)  hot lava flows over rocks, causing them to become metamorphic. 
B)  semi- molten volcanic bombs fuse together. 
C)  particles within a lahar cool and crystallize. 
D)  particles within a nue´e ardente cool and crystallize.

Which of the following events would you NOT expect from the gigantic Toba ash- flow eruption?

Discuss two of the secondary environmental effects associated with volcanic eruptions.

Describe the differences in the volcanic products of basaltic and rhyolitic volcanoes.

If a volcano has not erupted in the past few thousand years, but is likely to erupt sometime in the future, it is considered to be:

Discuss why efforts to predict volcanic eruptions sometimes fail.

What is the most common way of predicting volcanic eruptions?

Why is the Olympus Mons volcano on Mars so much larger than similar shield volcanoes on Earth?

Compared to rhyolitic lavas, basaltic lavas tend to be:

Which of the following statements regarding volcanoes is NOT true?

All of the following are likely environmental effects of a volcanic explosion EXCEPT:

Of the following, the magma with the highest viscosity would have:

Whether they are basaltic or rhyolitic, almost all volcanoes have both:

Explain why felsic magmas have a higher viscosity and retain gases more than mafic magmas.

All of the following events could indicate an impending eruption EXCEPT:

Which of the following is a likely product of a subaqueous basaltic eruption?

Which of the following characteristics would you NOT expect from an effusive eruption?

What are ash- flow eruptions?

How did the cataclysmic eruption of Krakatau in 1883 affect global climate?

Volcanoes are beneficial to humanity in many ways. All of the following are benefits EXCEPT:

A welded tuff forms when:

A First Look at Planet Earth - Its Origins, Systems, and Tectonic Plates

Minerals

Igneous Rocks and Processes

Weathering - the Breakdown of Rocks

Sedimentary Processes, Environments, and Rocks

Metamorphism and Metamorphic Rocks

Telling Time Geologically

Earth Structures - Folds, Faults, and Fabrics

Earthquakes

The Earths Interior - Whats Going on Down There

Plate Tectonics and the Formation of the Earths Oceans

Continental Tectonics and the Formation of the Earths Continents

Mass Movement

Streams and Floods

Groundwater

Glaciers and Ice Ages

Deserts and the Work of Winds

Shores and Coastal Processes

Human Use of the Earths Resources Appendices Glossary

Filters

Exam 4: Volcanoes and Volcanism

Which of the following events would you NOT expect from the gigantic Toba ash- flow eruption?

Discuss two of the secondary environmental effects associated with volcanic eruptions.

Describe the differences in the volcanic products of basaltic and rhyolitic volcanoes.

If a volcano has not erupted in the past few thousand years, but is likely to erupt sometime in the future, it is considered to be:

Discuss why efforts to predict volcanic eruptions sometimes fail.

What is the most common way of predicting volcanic eruptions?

Why is the Olympus Mons volcano on Mars so much larger than similar shield volcanoes on Earth?

Compared to rhyolitic lavas, basaltic lavas tend to be:

Which of the following statements regarding volcanoes is NOT true?

All of the following are likely environmental effects of a volcanic explosion EXCEPT:

Of the following, the magma with the highest viscosity would have:

Whether they are basaltic or rhyolitic, almost all volcanoes have both:

Explain why felsic magmas have a higher viscosity and retain gases more than mafic magmas.

All of the following events could indicate an impending eruption EXCEPT:

Which of the following is a likely product of a subaqueous basaltic eruption?

Which of the following characteristics would you NOT expect from an effusive eruption?

What are ash- flow eruptions?

How did the cataclysmic eruption of Krakatau in 1883 affect global climate?

Volcanoes are beneficial to humanity in many ways. All of the following are benefits EXCEPT:

A welded tuff forms when:

A First Look at Planet Earth - Its Origins, Systems, and Tectonic Plates

Minerals

Igneous Rocks and Processes

Weathering - the Breakdown of Rocks

Sedimentary Processes, Environments, and Rocks

Metamorphism and Metamorphic Rocks

Telling Time Geologically

Earth Structures - Folds, Faults, and Fabrics

Earthquakes

The Earths Interior - Whats Going on Down There

Plate Tectonics and the Formation of the Earths Oceans

Continental Tectonics and the Formation of the Earths Continents

Mass Movement

Streams and Floods

Groundwater

Glaciers and Ice Ages

Deserts and the Work of Winds

Shores and Coastal Processes

Human Use of the Earths Resources Appendices Glossary

Filters