Science Olympiad Dynamic Planet Practice Test

What typically happens at convergent plate boundaries?

1. Plates move apart

2. Continental plates collide

3. Oceanic plates subduct under continental plates

4. Plates glide past each other horizontally

The correct answer is: Oceanic plates subduct under continental plates

At convergent plate boundaries, significant geological activities occur due to the interaction of tectonic plates. One of the defining features of these boundaries is the subduction process, particularly where oceanic plates meet continental plates. When an oceanic plate converges with a continental plate, the denser oceanic plate is forced downward into the mantle beneath the continental plate. This process can lead to the formation of deep ocean trenches, volcanic arcs, and mountain ranges. Subduction has important implications for geological events like earthquakes and volcanic eruptions. As the oceanic plate descends, it can cause melting of mantle rocks, leading to magma formation that can rise to the surface and result in volcanic activity. The stress and friction at these boundaries are also responsible for some of the strongest earthquakes on Earth. The other scenarios presented, such as plates moving apart, plates gliding past each other, or the collision of continental plates (without involving subduction), do not accurately represent the key characteristics of convergent boundaries. Therefore, the subduction of oceanic plates under continental plates is a fundamental and defining process at convergent plate boundaries.