The diagram shows the growth cycle of a volcanic island. Write a 150-word report for a university lecturer describing the main features of the cycle. Write at least 150 words. IELTS 7 band essay 2023
The illustration depicts a natural process in which an underwater volcanic island
forms, erupts, and eventually descends to become a submerged reef. There are
nine phases in the process.
Body paragraph 1
A mountain gradually develops beneath the sea’s surface in the first two phases,
known as the “Preshield” and “Protoshield” stages. A cone of ash is left behind by hydro-explosions that take place in the third, or “explosive,” phase. Afterward, cinder cones clump together to form a “shield” on top of the volcano.
Body paragraph 2
Under the water’s surface, this shield steadily erodes and sinks, giving rise to
reefs. There could, however, be lava flows and other ongoing volcanic activity.
The volcano’s initial form has vanished by the time it reaches the “coral atoll”
stage, and during the “Guyot” stage the entire structure continues to submerge.
In conclusion, the volcanic island growth cycle is a natural process in which
enormous volcanoes rise and sink beneath the water.