Mountains form through tectonic processes that reshape Earth’s crust over millions of years. When two continental plates converge, immense compressional forces cause the crust to shorten, thicken, fold, and uplift, forming towering mountain ranges such as the Himalayas. At subduction zones, where one tectonic plate sinks beneath another, fluids released from the subducting slab trigger partial melting in the overlying mantle, generating magma that can rise and form volcanic mountain ranges such as the Andes. In other regions, tectonic forces stretch and fracture the crust along faults, causing large blocks of rock to be uplifted while others sink, producing fault block mountains.