Fuse means, essential component is a metal wire or strip that melts when too much current flows, which breaks the circuit in which it is connected, thus protecting the circuit's other components from damage due to excessive current. I hope that helps.
Rift volcanoes occur where tectonic plates diverge, often on the ocean floor. These are generally less explosive. Hot spot volcanoes occur in the middle of plate boundaries where magma exits from weaknesses in the earth's surface. The Hawaiian Islands are an example of hot spot volcanoes. The most active area of volcanic activity occurs along the pacific plate boundary which is often referred to as the 'Pacific ring of fire'.
volcanic activity probably occurs in response to a change in the local pressure surrounding the magma reservoir system as a consequence of (1) severe ground shaking caused by the earthquake; or (2) a change in the strain or pressure in the Earth's crust in the region