What is the function of the peripheral system and its function? peripheral nervous system is all the nerves located outside the  central nervous system; connects the central nervous system to all  the parts of the body. 1 person found this useful.
Volcanoes are formed when magma from within the Earth's upper mantle works its way to the surface. At the surface, it erupts to form lava flows and ash deposits. Over time as the volcano continues to erupt, it will get bigger and bigger.
Volcanoes can form in three geologic settings, all of which result in the melting of rock in the upper part of the mantle. The rock in the mantle is very hot but is kept solid under immense pressure. Some volcanoes form at divergent boundaries where two of Earth's tectonic plates pull apart. The crust is thin at these boundaries, reducing pressure on the mantle, allowing some melting to occur, forming molten rock called magma. This rises to the surface, forming volcanoes.