GEOLOGY

Detailed explanation-1: -Island arcs are long chains of active volcanoes with intense seismic activity found along convergent tectonic plate boundaries. Most island arcs originate on oceanic crust and have resulted from the descent of the lithosphere into the mantle along the subduction zone .

Detailed explanation-2: -A subduction zone is also generated when two oceanic plates collide-the older plate is forced under the younger one-and it leads to the formation of chains of volcanic islands known as island arcs.

Detailed explanation-3: -At a convergent plate boundary, when one plate is oceanic, there are large volcanoes. These volcanoes are found in lines that outline the subduction zone. Earthquakes also happen in these zones. Subduction of an oceanic plate beneath a continental plate forms a line of volcanoes known as a continental arc.

Detailed explanation-4: -When two oceanic plates collide against each other, the older and therefore heavier of the two subducts beneath the other, initiating volcanic activity in a manner similar to that which occurs at an oceanic-continental convergent plate boundary and forming a volcanic island arc.

Detailed explanation-5: -Volcanoes are one kind of feature that forms along convergent plate boundaries, where two tectonic plates collide and one moves beneath the other.