👉 A volcano is a type of mountain or rock formation that erupts due to the release of molten magma from within. Volcanic activity can occur on Earth's surface, including in the form of volcanic eruptions and lava flows. Volcanic eruptions are typically caused by the rapid heat generated when the interior of a volcano is heated up to a high enough temperature. The magma that rises from the volcano's interior can then cool down and solidify into rocks or minerals, creating new layers