Answer :
A rift is a type of valley that forms in a subduction zone.
Sea floor spreading is the process in which molten material spews from the mantle, soon to be pressurized. Once there is enough pressure, it pushes the old sea floor into subduction zones causing rift valleys to form. Sea-floor spreading is also a cause of continental drift.
Sea floor spreading is the process in which molten material spews from the mantle, soon to be pressurized. Once there is enough pressure, it pushes the old sea floor into subduction zones causing rift valleys to form. Sea-floor spreading is also a cause of continental drift.