The boundary where the two plates meet is called a convergent boundary ... magma that makes its way to the surface, producing volcanoes, such as Mt. St. Helens. Most of the subducting plate ...

The tiny Juan de Fuca plate is largely responsible for the volcanoes that dot the Pacific ... the plates creates three types of tectonic boundaries: convergent, where plates move into one another ...

Tall, steep volcanoes can also form as a result of the denser rock melting and the magma being forced up to the surface. South America has a great example of a convergent plate boundary.