The deep oceans are far from flat. They feature ridges, trenches, seamounts, and valleys, creating a diverse and dramatic ...

These convergent boundaries also occur where a plate of ... In addition, the diving plate melts and is often spewed out in volcanic eruptions such as those that formed some of the mountains ...

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 ...

Trigger volcanoes. Create new sea floor ... Also known as subduction boundary, a convergent boundary occurs where one plate slides under another as the two are pushed together.

The magma escapes through weaknesses in the rock and rises up through a composite volcano. The volcanic eruptions are often violent, with lots of steam, gas and ash.

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.