Destructive boundaries are responsible for the world’s most violent volcanism. As the subducting plate descends, it undergoes chemical changes that release water. This water causes “flux melting” in the overlying mantle wedge. The resulting magma is often rich in silica and gas, leading to highly explosive “stratovolcanoes.” While volcanoes also occur at constructive boundaries (Mid-ocean ridges), those eruptions are mostly underwater and less explosive. Therefore, the most visible and impactful volcanic events—those that build high mountains and affect climate—are almost exclusively linked to destructive margins.