The external crust of the Earth consists of a series of tectonic plates moving on the planet's surface. Often volcanoes are created in regions where the plates come together. Volcanoes also can grow in the middle of a rock, which is named "Hot Spot," where the magma rises up until it bursts on the sea floor. A hot spot in the center of the Pacifical Rock is created on the Hawaiians Islands. The plate shifts, while the hot spot remains set. So the chain of the islands that comprise the Hawaiian Island chain was formed when this plate moved over the hot spot.
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