destructive boundary - convergent boundary, also known as a destructive plate boundary, is a region of active deformation where two or more tectonic plates or fragments of the lithosphere are near the end of their life cycle.
ocean trench - a long, narrow, deep depression in the ocean floor, typically one running parallel to a plate boundary and marking a subduction zone.
island arc - a curved chain of volcanic islands located at a tectonic plate margin, typically with a deep ocean trench on the convex side