Final answer:
A subduction zone is formed when tectonic plates collide, where one plate is forced beneath another. Thinner oceanic plates are usually subducted under thicker continental plates.
Step-by-step explanation:
A subduction zone is formed when tectonic plates collide. It is a region where one tectonic plate is forced beneath another. This often happens with thinner oceanic plates being thrust beneath thicker continental plates. An example of a subduction zone is the deep Japan trench along the coast of Asia.