A linear or arc-shaped chain of volcanic islands formed at a convergent plate boundary. The island arc is formed in the overriding plate from rising melt derived from the subducted plate and from the asthenosphere above that plate.
More specific than the term might appear. Island arcs are crescent-shaped aligned chains of volcanoes, formed above subduction zones.
A group of islands located on an oceanic plate that have a curving, arc-shaped pattern of distribution. The islands in an island arc are the result of convergent plate volcanism over a subduction zone.