If the overriding plate is oceanic crust, what feature forms parallel to the trench?

Answer

An island arc

When an oceanic plate subducts beneath another oceanic plate, the resulting volcanic activity builds up from the seafloor until it emerges as a chain of volcanic islands known as an island arc.

If the overriding plate is oceanic crust, what feature forms parallel to the trench?

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BEHIND THE SCIENCE 2011 | Subduction Zone Volcanoes

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