What correctly describes volcanism at a continental volcanic arc? - Answers 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______? - Answers In valleys,denser than air
what magma type is produced by partial melting of the Earth's mantle? - Answers Mafic
Fatalities from volcanic eruptions have increased steadily over the past 200 years because _________. -
Answers 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. - Answers True
What type of volcanic landform is MOST commonly associated with Hawaiian mafic volcanism? -
Answers Shield Volcano
A high volcano explosivity index (VEI) generally corresponds with _________. - Answers Long recurrence
intervals
The type of magma most likely to cause a violent volcanic eruption is________. - Answers high viscosity
and relatively cool
True or False:All minerals have Si and O. - Answers False
What is NOT measured in volcano monitoring programs - Answers temperature of the magma body at
depth
What was the volcanic hazard that caused the tragedy at Lake Nyos in Cameroon? - Answers Co2 gas
Pyroclastic flows don't originate in _______. - Answers fall of ballistic debris
A common example of a mafic volcanic landform is a ________. - Answers Shield Volcano
A hazard NOT caused by volcanic ash and ash clouds is: - Answers causing a tsunami when ash falls into
the ocean
Most magma is generated by melting of pre-existing rock through _________. - Answers decompression
melting
The majority of the world's explosive volcanoes are found at: - Answers Convergent plate boundaries
Which volcanic hazards is the LEAST hazardous to humans? - Answers Lava
What is NOT a product of a volcanic eruption? - Answers intrusive igneous rocks
, The MOST LIKELY place to find an active subaerial volcano is ______. - Answers 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 _________. - Answers rhyolite pyroclastic flow in a caldera
he explosivity of hot spot volcanism is dictated by ? - Answers the composition of the overlying plate
True or False: about volcanism in an ocean-ocean convergence setting? Mafic-intermediate lavas are
common. - Answers True
How does a cinder cone form? - Answers Relatively short-lived eruptions of pyroclastic material build up
a small volcano.
Which volcanic hazard does hydrothermal alteration promote? - Answers Landslides
True or False: A Lava flow is is not typical of cinder cone eruptions - Answers False
Immediately after an eruption at Kilauea in Hawaii, the surface of the volcano ______. - Answers
subsides, making the slopes of the volcano less steep
Which of the following volcanic hazards is typically the DEADLIEST for people? - Answers pyroclastic
flows from stratovolcanoes
Which of the following eruptions had the highest Volcanic Explosivity Index (VEI)? - Answers Yellowstone
caldera, 600,000 years ago
Which volcano poses the GREATEST risk to life and property in Vancouver and southern British
Columbia? - Answers Mount Baker
Which magma composition will produce the most explosive volcanoes? - Answers Rhyolite
What magma has the highest viscosity ? - Answers Rhyolite
Which of the following poses the GREATEST hazard to the Metro Vancouver area from a nearby volcanic
eruption? - Answers Ash Fall
Large eruptions from stratovolcanoes typically affect climate by ______. - Answers ejecting ash particles
that block sunlight and cause global cooling
How did the residents of Vestmannaeyjar, Iceland, save their harbor from a lava flow? - Answers They
chilled the lava flow with water, making the flow solidify before it blocked the harbor.
Which of the following is the most common volcanic rock on Earth? - Answers Basalt
Aircraft flying at high altitudes between North America and Asia can be very susceptible to ______
erupted from volcanoes in Cascadia and Alaska. - Answers Volcanic Ash