Volcano Quiz
Questions: 16 · 10 minutes
1. Which volcano's AD 79 eruption buried the Roman cities of Pompeii and Herculaneum?
Vulcano
Mount Etna
Stromboli
Mount Vesuvius
2. Geologists find a very broad volcano with gentle slopes built mainly from repeated fluid basaltic lava flows. What type is it?
Lava dome
Stratovolcano
Cinder cone
Shield volcano
3. Monitoring shows an eruption beginning beneath an ice cap. Which immediate downstream hazard deserves special attention?
A permanent halt to all river flow as ash absorbs the meltwater
A slow-moving lava dome forming only at the river mouth
A saltwater surge created by cooling magma beneath the glacier
A sudden glacial outburst flood produced by rapidly melted ice
4. Why did the 1991 eruption of Mount Pinatubo temporarily cool average global temperatures?
Its lava absorbed large quantities of heat from the surrounding atmosphere
Sulfur-derived aerosols in the stratosphere reflected some incoming sunlight
Its ash significantly slowed warm ocean currents for several years
Carbon dioxide from the eruption rapidly removed water vapor from the air
5. A volcano begins showing more shallow earthquakes, rapid ground swelling, and changing gas emissions. What is the best interpretation?
Magma or volcanic fluids may be moving beneath the volcano
The volcano is permanently sealing its main vent
Weathering is converting the volcanic cone into a caldera
The volcano has changed from an active volcano into an extinct one
6. Why did the 1985 eruption of Nevado del Ruiz cause catastrophic loss of life in Armero, even though the eruption itself was not exceptionally large?
A lava lake drained directly into the town
A debris avalanche displaced a large coastal bay
Ash caused buildings to ignite across the town
Meltwater mixed with volcanic material, producing lahars that followed river valleys
7. After a huge explosive eruption, geologists find a wide, basin-like depression where the summit once stood. Which process best explains it?
A single lava flow cooled into a broad, shallow crater
The roof above a partly emptied magma reservoir collapsed
Wind removed the summit's rock immediately after the eruption
A new tectonic plate boundary formed beneath the summit
8. Residents near an explosive volcano are warned about pyroclastic flows. Why are these flows especially dangerous?
They consist of slow lava that remains hazardous only when touched
They are fast, ground-hugging currents of hot gas, ash, and debris
They release invisible gas but do not carry hot rock or ash
They occur only underwater and threaten ships rather than communities
9. After an eruption leaves loose ash on steep slopes, heavy rain is forecast. Which area faces the greatest lahar exposure?
A ridge above the volcano's drainage channels
A plateau separated from the volcano by a high divide
A settlement beside a river valley draining the volcano
A coastal headland outside the volcano's watershed
10. Which 1815 eruption is strongly associated with the climatic disruption behind 1816's “Year Without a Summer”?
Mount Tambora
Mount Pelée
Novarupta
El Chichón
11. Two explosive eruptions are assigned different values on the Volcanic Explosivity Index, or VEI. What does that scale primarily compare?
The age and total height of each volcanic mountain
The temperature and travel speed of individual lava flows
Explosive eruption size using evidence such as ejecta volume and eruption-cloud height
The number of people living within a fixed distance of each crater
12. The destructive 1883 eruption of Krakatau occurred in which setting?
The Mozambique Channel between Madagascar and Africa
The Tsugaru Strait between Honshu and Hokkaido
The Sunda Strait between Java and Sumatra
The Strait of Messina between Sicily and mainland Italy
13. Which volcano famously began forming in a Mexican cornfield in 1943 and was observed as it developed into a cinder cone?
Popocatépetl
Parícutin
El Chichón
Colima
14. Which consequence is particularly associated with the 1783-1784 Laki eruption in Iceland?
The sudden burial of Pompeii beneath pumice and ash
A lateral blast caused by the collapse of a bulging mountainside
A widespread sulfurous haze with serious health and agricultural effects
The emergence of a new cinder cone in a Mexican cornfield
15. What immediately preceded and helped trigger the devastating lateral blast at Mount St. Helens in 1980?
A major landslide removed the volcano's bulging north flank
A glacier collapsed into the crater and sealed the volcanic vent
A caldera formed as the entire summit slowly subsided
A lava flow entered Spirit Lake and caused a steam explosion
16. The Hawaiian Islands become progressively older toward the northwest, away from the volcanically active Island of Hawaiʻi. What is the best inference?
The Pacific Plate has moved northwest over a relatively stationary hotspot
Each island formed at the same time but cooled at a different rate
The hotspot is moving northwest faster than the Pacific Plate
The islands mark a spreading boundary that repeatedly reverses direction