A volcanic eruption can be very destructive. The lava flow, for one thing, not only destroys everything in its path, it can also alter the entire ecosystem of the area, wiping out both plants and animals. For another, the mudslides or rockslides caused by the eruption may bury many houses and field, as may the volcanic ash which can cover whole towns and villages. The eruption may also shake the ground so much, it may set off a large earthquake or a tsunami!