Volcanoes often form along the edges of where the plates meet. • Most volcanoes and earthquakes, about 80%, happen close to where two (tectonic) plates meet. • In the last 200 years, more than 50 volcanoes in the United States have erupted one or more times. read more
A volcano is a landform (usually a mountain) where molten rock erupts through the surface of the planet. In simple terms a volcano is a mountain that opens downward to a pool of molten rock (magma) below the surface of the earth. read more