Types of plate boundaries. At divergent plate boundaries, two plates move apart; they are typically associated with a mid-ocean ridge (also called a spreading center). At convergent plate boundaries, two plate move toward one another. If one or both plates contains oceanic crust, one plate dives, or subducts, beneath the other; a deep-sea trench marks the location where the downgoing plate bends downward. At transform plate boundaries, the two plates slide past one another; a large fault or fault system marks this type of plate boundary. From the USGS website This Dynamic Planet.