What happens when two tectonic plates collide?
When two oceanic plates collide, the denser oceanic plate will subduct beneath the lighter one, forming a subduction zone as well. They can also form (volcanic) island arcs such as the Solomon islands. However, the Hawaii island chain is NOT formed at convergent plate boundaries but at a hotspot, located beneath the oceanic plate. Magma rises up and forms a volcanic island, but as the oceanic plate moves, the hotspot remains at the same position, forming new volcanic islands. The volcanoes on the other islands are then extinct as they are cut off from the magma source.
