Mount Pelee was formed at an ocean-ocean convergent plate boundary. Where the oceanic crust of one plate converges with the oceanic crust of another, the more dense plate will subduct under the less dense plate. In this case, the North America Plate subducted under the Caribbean Plate (Lloyd, Edwards, 2006). The magma that was produced when the crust subducted rises to the surface and forms an island arc, or a chain of volcanic islands. The island of Martinique is an example of this.