The Andes are folded mountains that form the longest mountain range orn Earth. How do folded mountains form?

Folded mountains form when two tectonic plates meet face to face and force rocks to raise to give room at the bottom. That forms a series of edges ... that can pile up and get very high, as in the case of the Andes, which were formed by the compression of the encounter of the Nazca plate and the South American plate.

The folded mountains are formed when two plates share a convergent plate boundary. These are the region where the plates are subjected to compressional stress from both sides.

The Andes mountain is an example of the folded mountains that are formed due to the convergent of Nazca and the South American plate. It forms the longest mountain range in the world extending from the northwestern to the Southwestern side of South America through the west.

As the plates converge, the heavier plate subducts and melts at great depth and after mixing up with the magma, it again rises up due to the force exerted by the convection current. It then rises up towards the over-riding plate, giving rise to the formation of volcanoes and volcanic arcs.