Formation of mountain ranges
Although we have already seen the different boundaries between tectonic plates, as a review, we will see the main geological processes that occur when two tectonic plates converge. It is in the subduction zones where the destruction of the lithosphere occurs, the lithosphere created in the ridges returning to the mantle. Here, the incoming lithosphere has cooled, has more sediment, and is denser, so it sinks under the other plate.
Several situations are distinguished:
- Collision between two oceanic plates. One plate subducts under the other, creating an oceanic trench. Sometimes the subducing plate partially melts and, together with the sediments, volcanoes appear that create arch islands. In these areas there is great volcanic and seismic activity, such as the Pacific Island arches (Philippine Trench and Mariana Trench).