Question

Use the diagram to answer each question. Describe an exception to the patterns pictured at A and B where volcanoes also can form.

Answer 1

Exceptions to A and B are when volcanoes form at hot spots in the middle of continental or oceanic plates. Magma melts through the crust and moves to the surface in a hot spot. Also a collision between two oceanic plates can form volcanoes. One of the oceanic plate is subducted which melts the plate and the formation of magma which erupts to form a chain of volcanic islands called an island arc.

Answer 2

In the graph, we can see the two most common forms that give rise to volcanoes. Point A represents the generation of a volcano in the submarine bed or ocean floor that, when it erupts, can form islands or abyssal hills. Point B represents the boundary between two tectonic plates because stress cracks form at the pressure edges of two plates. The third case of volcanoes that form far from the limits of the plates is due to the existence of a hot spot in the earth's mantle, whereby heat starts to escape. This case is commonly visible on the island of Hawaii.