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 are the deepest parts of the ocean, with the Mariana Trench near Guam having the deepest spot on Earth (the Challenger Deep). Most ocean trenches are in the Pacific. The loss of the earth's crust at ocean trenches is made up for by seafloor spreading elsewhere, which is when tectonic plates are pulling apart.