Question

An island arc complex is formed where

Answer 1

These volcanoes can make a chain of islands called an "island arc". Examples of island arcs are the Japanese islands, the Kuril Islands, and the Aleutian Islands of Alaska, shown here. Island Arcs are formed on the opposing edge of a subducted slab. For each case, there is an associated subducting slab and a trench

Answer 2

Tectonic formation.... On the sub-ducting side of the island arc is a deep and narrow oceanic trench, which is the trace at the Earth's surface of the boundary between the down going and overriding plates.

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