Andean-type mountain belt

An Andean-type mountain belt is a geological formation characterized by crustal shortening and thickening, typically found at active continental margins where oceanic lithosphere subducts beneath a continental plate. While some Andean-type margins feature prominent volcanoes, others, like the Andes in South America, are characterized by high mountains even in the absence of significant volcanic activity.1

The formation of these belts involves the intrusion of magma from the mantle and crustal shortening, which can occur through overthrusting of crystalline terrain and the development of fold and thrust belts within sedimentary rocks. Compared to collision zones like the Himalayas, the scale of deformation and uplift in Andean-type belts is generally less pronounced. The Andes, for example, are a prime example, formed by the convergence of the Nazca and South American plates, resulting in both volcanic activity and significant crustal shortening.123