EAPS 106 UNITS 4 – 6 EXAM
QUESTIONS AND ANSWERS
What kind of volcano forms when tephra (air cooled lava fragments) is thrown out of a
volcanic vent? - Correct Answers -A cinder cone
True or False: Unlike earthquakes, at least some volcanic eruptions can be predicted a
few days before they occur. - Correct Answers -True
True or False: The bodies of the Pompeii dead hardened over time due to the pressure
of overlying ash, and thus were easy to recover intact 2000 years later. - Correct
Answers -False
How was Pompeii preserved for 2000 years? - Correct Answers -Beneath ash
True or False: Despite being many kilometers below the surface, it is possible to
monitor the changes in pressure of a magma chamber as a function of time. - Correct
Answers -True
What is a harmonic tremor? - Correct Answers -Ground shaking caused by the
movement of magma beneath the surface
What caused the tsunami that killed 36,000 people in Indonesia in 1883? - Correct
Answers -A volcanic eruption
In which direction does an island above a subducting plate move between earthquakes?
- Correct Answers -Downwards
How much bigger was the 2.1-million-year-old Yellowstone supereruption (VEI 8)
compared to the 1980 Mount St. Helens eruption (VEI 5)? - Correct Answers -1000
times bigger
What is the difference between magma and lava? - Correct Answers -Magma is found
below the Earth's surface; lava is found on the Earth's surface.
Why is Yellowstone considered a hidden supervolcano? - Correct Answers -Because
there is no obvious volcano observed in the park
, Why are there fewer active volcanoes in the southwestern US compared to the
northwestern US? - Correct Answers -Because there is not a subduction zone in the
southwest
What are giant flood basalts? - Correct Answers -Very large lava flows that occur in a
relatively short amount of time
True or False: Slip on an underwater strike-slip faults can cause a significant tsunami. -
Correct Answers -False
True or False: The wave heights (10 meters) of the 2011 Japan tsunami were
unprecedented in Japan's history, and thus it is understandable that they were not
prepared for it. - Correct Answers -False
Which has the potential to cause the largest tsunamis? - Correct Answers -An asteroid
impact
Why is the Toba supereruption 74,000 years ago considered such an important historic
event? - Correct Answers -Because it may have influenced the evolution of humans
Who was Pliny the Younger? - Correct Answers -An eyewitness to the destruction of
Pompeii who wrote down what he saw
What is an effusive volcanic eruption? - Correct Answers -One in which lava flows out of
a volcano
For the vast majority of the mantle, which is higher, the actual temperature or the
melting temperature? - Correct Answers -The melting temperature
What volcanic process (setting) created Mount Vesuvius? - Correct Answers -
Subduction zone volcanism
At the shore, why does the sea level often drop dramatically before a tsunami arrives? -
Correct Answers -Because the wave trough often arrives before the wave crest
What causes hot rocks to melt at subduction zones? - Correct Answers -Hydration-
induced melting
How do we know Yellowstone is a hot spot volcano? - Correct Answers -Because it lies
at the end of a trail of extinct volcanoes
Which is the most powerful type of explosive eruption? - Correct Answers -Plinian
Which hazard near a volcano leads to the least number of deaths? - Correct Answers -
Lava flows
QUESTIONS AND ANSWERS
What kind of volcano forms when tephra (air cooled lava fragments) is thrown out of a
volcanic vent? - Correct Answers -A cinder cone
True or False: Unlike earthquakes, at least some volcanic eruptions can be predicted a
few days before they occur. - Correct Answers -True
True or False: The bodies of the Pompeii dead hardened over time due to the pressure
of overlying ash, and thus were easy to recover intact 2000 years later. - Correct
Answers -False
How was Pompeii preserved for 2000 years? - Correct Answers -Beneath ash
True or False: Despite being many kilometers below the surface, it is possible to
monitor the changes in pressure of a magma chamber as a function of time. - Correct
Answers -True
What is a harmonic tremor? - Correct Answers -Ground shaking caused by the
movement of magma beneath the surface
What caused the tsunami that killed 36,000 people in Indonesia in 1883? - Correct
Answers -A volcanic eruption
In which direction does an island above a subducting plate move between earthquakes?
- Correct Answers -Downwards
How much bigger was the 2.1-million-year-old Yellowstone supereruption (VEI 8)
compared to the 1980 Mount St. Helens eruption (VEI 5)? - Correct Answers -1000
times bigger
What is the difference between magma and lava? - Correct Answers -Magma is found
below the Earth's surface; lava is found on the Earth's surface.
Why is Yellowstone considered a hidden supervolcano? - Correct Answers -Because
there is no obvious volcano observed in the park
, Why are there fewer active volcanoes in the southwestern US compared to the
northwestern US? - Correct Answers -Because there is not a subduction zone in the
southwest
What are giant flood basalts? - Correct Answers -Very large lava flows that occur in a
relatively short amount of time
True or False: Slip on an underwater strike-slip faults can cause a significant tsunami. -
Correct Answers -False
True or False: The wave heights (10 meters) of the 2011 Japan tsunami were
unprecedented in Japan's history, and thus it is understandable that they were not
prepared for it. - Correct Answers -False
Which has the potential to cause the largest tsunamis? - Correct Answers -An asteroid
impact
Why is the Toba supereruption 74,000 years ago considered such an important historic
event? - Correct Answers -Because it may have influenced the evolution of humans
Who was Pliny the Younger? - Correct Answers -An eyewitness to the destruction of
Pompeii who wrote down what he saw
What is an effusive volcanic eruption? - Correct Answers -One in which lava flows out of
a volcano
For the vast majority of the mantle, which is higher, the actual temperature or the
melting temperature? - Correct Answers -The melting temperature
What volcanic process (setting) created Mount Vesuvius? - Correct Answers -
Subduction zone volcanism
At the shore, why does the sea level often drop dramatically before a tsunami arrives? -
Correct Answers -Because the wave trough often arrives before the wave crest
What causes hot rocks to melt at subduction zones? - Correct Answers -Hydration-
induced melting
How do we know Yellowstone is a hot spot volcano? - Correct Answers -Because it lies
at the end of a trail of extinct volcanoes
Which is the most powerful type of explosive eruption? - Correct Answers -Plinian
Which hazard near a volcano leads to the least number of deaths? - Correct Answers -
Lava flows
