Forbidden Knowledge TV
September 7, 2010
Most volcanoes occur near the in-transit edges of tectonic plates, in what’s called the subduction zone.
Some volcanoes are created when plates collide. An ocean plate basin, for example, can dive beneath a land plate, which usually consumes the ocean plate. This can drive magma to the surface, causing pressure to build and volcanic eruption.
This is how Mount St. Helens went off.