Biology 210 with Walsh at Trident Technical College *. * The material on this site is created by StudyBlue users. StudyBlue is not affiliated with, sponsored by or endorsed by the academic institution or instructor.
Mid-ocean ridges (eg. Mid Atlantic Ridge) are formed at constructive plate boundaries, where magma is welling up between two diverging plates and forming new plate materiel. Trenches (eg. Marianas Trench) are formed at destructive plate boundaries where an ocean plate is being subducted below a continental plate.Chariotmender Â· 8 years ago.id Atlantic Ridge) are formed at constructive plate boundaries, where magma is welling up between two diverging plates and forming new plate materiel. Trenches (eg. Marianas Trench) are formed at destructive plate boundaries where an ocean plate is being subducted below a continental plate. Chariotmender Â· 8 years ago.
Trenches are generally parallel to a volcanic island arc, and trenches about 200 km from a volcanic arc. Oceanic trenches typically extend 3 to 4 km (1.9 to 2.5 mi) below the level of the surrounding oceanic floor. The deepest ocean depth to be sounded is in the Challenger Deep of the Mariana Trench at a depth of 10,911 m (35,798 ft) below sea level.