What type of convergent plate boundary is found along the west coast of South America where there is an ocean trench offshore and the Andes Mountains onshore?
1 Answer
This convergent plate boundary is called a subduction zone.
Explanation:
On the west coast of South America the denser ballistic ocean crust of the pacific plate is pushed under the lighter granite continental crust of South America. This causes a sub duction zone.
The ocean crust is push down creating a trench. As the ocean crust is pushed under the continental crust, the continental crust is pushed upwards creating the Andes mountains. Much of the ocean crust is melted as it pushed under. This melted crust become magma which pushes up creating the volcanos found along the Andes mountains.
The fossils and sedimentary layers of the older ocean crust are destroyed during the subduction process. How thick layers of ocean sedimentary layers are deposited on the continents is a problem given the characteristic of the ocean continent convergent boundaries.
