What geological process can result in the formation of mountain ranges?

Mountain ranges primarily form through the process of subduction, which occurs when one tectonic plate moves under another and sinks into the mantle. This leads to intense geological activity, including the folding and faulting of the Earth's crust. As the descending plate melts and interacts with the overlying plate, it can create volcanic activity, but more importantly, it causes the uplift of the continental crust, leading to the formation of mountain ranges such as the Andes as a result of the collision between the Nazca and South American plates.

While weathering, glaciation, and volcanism can contribute to the landscape and formation of features in mountains, they do not themselves primarily create mountain ranges. Weathering refers to the breakdown of rocks at the surface through various processes, glaciation is associated with the action of glaciers sculpting landforms but does not create mountains from the underlying geological structures, and volcanism refers to the eruption of magma which can build up volcanic mountains but is often a result of processes such as subduction or rifting. Thus, subduction is the key geological process behind the large-scale formation of mountain ranges.