Analyze the tectonic genesis and morphology of island arc systems: Statement I: Island arcs such as the Japanese archipelago and the Aleutian Islands are curved chains of volcanic islands formed at ocean-ocean convergent subduction zones. Statement II: The trench side of an island arc typically features a forearc basin and an accretionary wedge formed by scraping off sediment from the subducting oceanic plate.

💡 Solution & Explanation

Both statements are correct and directly interrelated. Island arcs form along convergent boundaries where an oceanic plate subducts beneath another oceanic plate, melting mantle material to produce volcanic chains. The associated subduction trench system creates forearc structural depressions and accretionary prisms where marine sediments are deformed against the overriding plate edge. Arc volcanism is responsible for seismic and volcanic hazards in regions like the Pacific Ring of Fire.