Hawaiian islands are volcanic in nature and have formed as a result of tectonic plate movements over a hot spot. The point of contact of tectonic plates is a good location for volcanoes. However, sometimes volcanoes can also form in the middle of the tectonic plate and will release magma on the sea floor. Such volcanic regions that are fed by the mantle are known as hot spot. Hawaiian islands were formed due to Hawaiian Hot spot. The location of hot spot is fixed, however the tectonic plate (Pacific plate in this case) moves over it. This results in formation of islands. Since the plate is moving in the northwest direction, the islands are older as one moves in the northwest direction. As the plate moves over the hot spot, the magma release results in formation of volcano and as the region moves away, the volcano stops erupting and gets older and older as we move away from the hotspot (in northwest direction).
The youngest formation in the Hawaiian island series is Loihi and as we move in the northwest direction, islands get older and so do the volcanoes. Currently the Hawaiian hotspot is under the Big Island and the pacific plate is moving at 5-10 cm/yr. This motion has results in the formation of the chain of islands known as Emperor Seamount.
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It is hypothesized that the Hawaiian Islands were, and still are forming, as a result of repeated volcanic eruptions that originate thousands of feet below the seafloor. The visible islands are the peaks of these volcanoes. Due to the movement of tectonic plates, which comprise the outer crust of the Earth’s surface, volcanoes are formed either where the plates meet or in the middle of the plate. In the case of the Hawaiian Island chain, it was formed by a hot spot in the middle of the Pacific Plate. As the plate moved over the “hot spot” lava flowed over several million years until the islands were formed as the tops of these volcanic mountains. Some of them rise over 30,000 feet above the seafloor. What we know as the Hawaiian Islands is only a small portion of the Hawaiian Ridge of the Emperor Seamount Chain. The chain is made up of over 80 large volcanoes. The Hawaiian Islands are a 1,500 mile long archipelago that reaches from Big Island of Hawaii in the southeast to the Kure Atoll in the northwest, which is comprised of 132 islands, atolls, shoals, and seamounts.
The Earth's crust is comprised of tectonic plates that move over the surface of our planet. In these areas where the plates come together, volcanos can form. Volcanos can also form in the middle of a tectonic plate, which is known as a hot spot. The Hawaiian Islands were formed from a hot spot that took place in the middle of the Pacific Plate. The hot spot itself is stationary, the plate is still moving. As the plate moved over the hot spot, the Hawaiian Island chain formed.