From Vesuvius to Laki, history has seen some monstrous volcanic eruptions. Many of these volcanoes are stratovolcanoes, meaning cone-shaped elevations built over time from layers of ash, lava, and other volcanic materials. Their steep slopes can produce deadly pyroclastic flows, making them among the most dangerous types of volcanoes.
The power of volcanic eruptions is measured using the Volcanic Explosivity Index (VEI), a scale ranging from zero to eight. Each increase represents a roughly tenfold increase in the volume of material ejected. Need examples? Click on to find out!