There’s a major belt of volcanoes around the edge of the Pacific Ocean, known as the Ring of Fire.
Hot Spots
Some volcanoes form in the middle of tectonic plates, far from the boundaries, in hot spots. These are places where the hot mantle melts, forces its way through the crust, and erupts as lava. Hot-spot volcanoes in the oceans form underwater mountains called seamounts. The Hawaiian Islands are the summits of giant seamounts.
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olcanoes form in places where magma forces its way out of a crack in Earth’s crust. This can happen at divergent faults, where two tectonic plates move apart, allowing magma to rise to the surface. Most of these volcanoes are located on the seafloor. Volcanoes can also occur at convergent faults, where two plates collide. One plate slides under the other and moves down into the mantle. This is called subduction, and the area where it happens is the subduction zone. The lower plate partially melts in the mantle, making new magma that rises up to form volcanoes.
Rising magma Continental crust
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Hawaii Hot spot
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Melting magma
