Which plate boundary type is associated with plates moving apart, often creating new crust at the ocean floor?

• A. Divergent
• B. Convergent
• C. Transform
• D. Subduction

Answer: (A)

Moving apart boundaries are where tectonic plates separate. At a divergent boundary, magma from the mantle rises into the gap, cools, and solidifies to form new crust—primarily oceanic crust that adds to the ocean floor as sea-floor spreading occurs at mid-ocean ridges. This is how new crust is continually created as plates pull away from one another. In contrast, convergent boundaries involve collision and possible subduction, while transform boundaries involve plates sliding past one another without creating new crust. So the scenario described—plates moving apart and forming new crust at the ocean floor—fits the divergent boundary.