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.
Ocean trenches have relatively steep sides falling to the ocean floor. Ocean trenches are typically caused when an oceanic crustal plate slides under a lighter continental plate or another oceanic plate. It is believed to work by density.Where one plate slides under another, this is called subduction.t least five trenches are over 6 miles (10 km) deep. The greatest ocean depth to be sounded is in the Challenger Deep of the Mariana Trench, at a depth of 11,034 m (36,201 ft) below sea level.