Answer:
Oceanic plate being destroyed
Explanation:
The convergence at this margin between the oceanic pacific plate and the Continental South American plate causes subduction here. 
At this margin, there is crustal destruction. 
- As the denser Pacific plate subducts under the less dense continental crust, it is increasingly destroyed. 
-  Most convergent margin of this type leads to the destruction of the crust. 
- Usually, on an adjacent side, there is a mountain building. 
- Basically, at this margin, the most important thing is that the crust is being destroyed.