EOSC 114 Volcanoes Questions with Correct
Answers
What correctly describes volcanism at a continental volcanic arc?
High Viscosity dacitic lavas and explosive volcanism
During the 1986 lake Nyos eruption, the most dangerous areas to be in
were_____because the gas was______?
In valleys,denser than air
what magma type is produced by partial melting of the Earth's mantle?
Mafic
Fatalities from volcanic eruptions have increased steadily over the past 200 years
because _________.
the world's population has increased and people are living closer to 100% volcanoes.
True or False:Mount St. Helens is a composite volcano that can erupt magmas with the
entire possible range of silica contents.
True
What type of volcanic landform is MOST commonly associated with Hawaiian mafic
volcanism?
Shield Volcano
The type of magma most likely to cause a violent volcanic eruption is________.
high viscosity and relatively cool
True or False:All minerals have Si and O.
,False
What is NOT measured in volcano monitoring programs
temperature of the magma body at depth
What was the volcanic hazard that caused the tragedy at Lake Nyos in Cameroon?
Co2 gas
Pyroclastic flows don't originate in _______.
fall of ballistic debris
A common example of a mafic volcanic landform is a ________.
Shield Volcano
A hazard NOT caused by volcanic ash and ash clouds is:
causing a tsunami when ash falls into the ocean
Most magma is generated by melting of pre-existing rock through _________.
decompression melting
The majority of the world's explosive volcanoes are found at:
Convergent plate boundaries
Which volcanic hazards is the LEAST hazardous to humans?
Lava
What is NOT a product of a volcanic eruption?
intrusive igneous rocks
The MOST LIKELY place to find an active subaerial volcano is ______.
, Above a subduction zone
A magma erupting at a temperature of 600-800°C, with high silica content, high gas
content, and high viscosity will erupt as a/an _________.
rhyolite pyroclastic flow in a caldera
he explosivity of hot spot volcanism is dictated by ?
the composition of the overlying plate
True or False: about volcanism in an ocean-ocean convergence setting? Mafic-
intermediate lavas are common.
True
How does a cinder cone form?
Relatively short-lived eruptions of pyroclastic material build up a small volcano.
Which volcanic hazard does hydrothermal alteration promote?
Landslides
True or False: A Lava flow is is not typical of cinder cone eruptions
False
Immediately after an eruption at Kilauea in Hawaii, the surface of the volcano ______.
subsides, making the slopes of the volcano less steep
Which of the following volcanic hazards is typically the DEADLIEST for people?
pyroclastic flows from stratovolcanoes
Which of the following eruptions had the highest Volcanic Explosivity Index (VEI)?
Answers
What correctly describes volcanism at a continental volcanic arc?
High Viscosity dacitic lavas and explosive volcanism
During the 1986 lake Nyos eruption, the most dangerous areas to be in
were_____because the gas was______?
In valleys,denser than air
what magma type is produced by partial melting of the Earth's mantle?
Mafic
Fatalities from volcanic eruptions have increased steadily over the past 200 years
because _________.
the world's population has increased and people are living closer to 100% volcanoes.
True or False:Mount St. Helens is a composite volcano that can erupt magmas with the
entire possible range of silica contents.
True
What type of volcanic landform is MOST commonly associated with Hawaiian mafic
volcanism?
Shield Volcano
The type of magma most likely to cause a violent volcanic eruption is________.
high viscosity and relatively cool
True or False:All minerals have Si and O.
,False
What is NOT measured in volcano monitoring programs
temperature of the magma body at depth
What was the volcanic hazard that caused the tragedy at Lake Nyos in Cameroon?
Co2 gas
Pyroclastic flows don't originate in _______.
fall of ballistic debris
A common example of a mafic volcanic landform is a ________.
Shield Volcano
A hazard NOT caused by volcanic ash and ash clouds is:
causing a tsunami when ash falls into the ocean
Most magma is generated by melting of pre-existing rock through _________.
decompression melting
The majority of the world's explosive volcanoes are found at:
Convergent plate boundaries
Which volcanic hazards is the LEAST hazardous to humans?
Lava
What is NOT a product of a volcanic eruption?
intrusive igneous rocks
The MOST LIKELY place to find an active subaerial volcano is ______.
, Above a subduction zone
A magma erupting at a temperature of 600-800°C, with high silica content, high gas
content, and high viscosity will erupt as a/an _________.
rhyolite pyroclastic flow in a caldera
he explosivity of hot spot volcanism is dictated by ?
the composition of the overlying plate
True or False: about volcanism in an ocean-ocean convergence setting? Mafic-
intermediate lavas are common.
True
How does a cinder cone form?
Relatively short-lived eruptions of pyroclastic material build up a small volcano.
Which volcanic hazard does hydrothermal alteration promote?
Landslides
True or False: A Lava flow is is not typical of cinder cone eruptions
False
Immediately after an eruption at Kilauea in Hawaii, the surface of the volcano ______.
subsides, making the slopes of the volcano less steep
Which of the following volcanic hazards is typically the DEADLIEST for people?
pyroclastic flows from stratovolcanoes
Which of the following eruptions had the highest Volcanic Explosivity Index (VEI)?
