四、閱讀測驗(請依照段落上下文意,選出最適當的答案) Mount Mayon, which is the most active volcano in the Philippines, is known for its
steep-sloped cone shape, which is often compared to Mount Fuji in Japan. Like other volcanoes
around the Pacific Ocean, Mayon is a part of the Pacific Ring of Fire. The Smithsonian reports that
the volcano’s picturesque symmetry makes it something of a tourist attraction, with visitors trying
to get to its rim. However, it is also the perfect cone shape that actually indicates how frequently the
volcano erupts and how dangerous the volcano can be. Its geology and location could soon combine
in explosive, and deadly, fashion.
Since Mayon’s first recorded eruption in 1616, it has erupted about 58 times, the latest one in this January, ranging from sputters to calamities. Many of Mayon’s eruptions have involved
spraying out lava that collects at the rim. As it sputters over the top, it builds up over time, causing
the steep slopes that have made it famous.
For comparison, the Italian volcano Mount Vesuvius of Pompeii has also erupted over 50
times in recorded history. In the past, Mount Vesuvius has had a roughly 20-year eruption cycle, the
last serious eruption in 1944. The best known eruption was in AD 79 that led to the burying and
destruction of the city of Pompeii for hundreds of years under many tons of volcanic ash unfolded
in much the same way -- explosions, ash raining down, air so thick that it’s hard to breathe, and then
finally a pyroclastic flow -- an explosive blast that sends ash, lava, and volcanic gas raining down
fast onto the sides of the volcano. It is the most devastating part of an eruption. It’s what buried
Pompeii, and Mayon may erupt in a similar fashion.
【題組】22. What is the most dangerous part of a volcano eruption?
(A) Gas and ash
(B) Thick air
(C) Pyroclastic flow
(D) Explosion