* Convergent plate boundaries: Where tectonic plates collide. This is the most common location for volcanic belts, as the subduction of one plate beneath another creates magma that rises to the surface. This leads to the formation of volcanic arcs along the edge of the overriding plate. Examples include the Andes Mountains, the Cascade Range in North America, and the Aleutian Islands.

* Divergent plate boundaries: Where tectonic plates move apart. Here, magma rises from the mantle to fill the gap, creating mid-ocean ridges and rift valleys. Examples include the Mid-Atlantic Ridge and the East African Rift Valley.

* Hotspots: Areas of volcanic activity that are not associated with plate boundaries. These are thought to be caused by plumes of hot mantle material rising to the surface. Examples include the Hawaiian Islands and the Yellowstone National Park.

In summary, volcanic belts primarily form along plate boundaries where tectonic activity generates magma, leading to volcanic eruptions.