The landforms that develop at plate boundaries where one oceanic plate descends beneath another are called subduction zones. These zones are characterized by a number of features, including:

* Ocean Trenches: These are deep, narrow depressions in the ocean floor that mark the location where the descending plate bends downward.

* Volcanic Arcs: As the descending plate melts, magma rises to the surface, forming chains of volcanoes on the overriding plate. These volcanoes can form both on land and in the ocean, creating island arcs.

* Earthquakes: Subduction zones are also associated with deep and powerful earthquakes. This is because the descending plate is constantly grinding against the overriding plate.

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