Hawaiian hotspot
Bathymetry of the Hawaiian – Emperor seamount chain, showing the long volcanic chain generated by the Hawaii hotspot, starting in Hawaiʻi and ending at the Aleutian Trench.
|
|
A diagram demonstrating the migration of the Earth's crust over the hotspot
|
|
| Country | United States |
|---|---|
| State | Hawaii |
| Region | North Pacific Ocean |
| Coordinates | 18°55′N 155°16′W / 18.92°N 155.27°W—Loihi Seamount, actual hotspot lies about 40 km (25 mi) southeastCoordinates: 18°55′N 155°16′W / 18.92°N 155.27°W—Loihi Seamount, actual hotspot lies about 40 km (25 mi) southeast |
The Hawaii hotspot is a volcanic hotspot located near the namesake Hawaiian Islands, in the northern Pacific Ocean. One of the most well-known and heavily studied hotspots in the world, the Hawaii plume is responsible for the creation of the Hawaiian – Emperor seamount chain, a chain of volcanoes over 5,800 kilometres (3,600 mi) long. Four of these volcanoes are active, two are dormant, and more than 123 are extinct, many having since been ground beneath the waves by erosion as seamounts and atolls. The chain extends from south of the island of Hawaiʻi to the edge of the Aleutian Trench, near the eastern edge of Russia. While most volcanoes are created by geological activity at tectonic plate boundaries, the Hawaii hotspot is located far from plate boundaries. The classic hotspot theory, first proposed in 1963 by John Tuzo Wilson, proposes that a single, fixed mantle plume builds volcanoes that then, cut off from their source by the movement of the Pacific Plate, become increasingly inactive and eventually erode below sea level over millions of years. According to this theory, the nearly 60° bend where the Emperor and Hawaiian segments of the chain meet was caused by a sudden shift in the movement of the Pacific Plate. In 2003, fresh investigations of this irregularity led to the proposal of a mobile hotspot theory, suggesting that hotspots are mobile, not fixed, and that the 47-million-year-old bend was caused by a shift in the hotspot's motion rather than the plate's.
Ancient Hawaiians were the first to recognize the increasing age and weathered state of the volcanoes to the north as they progressed on fishing expeditions along the islands. The volatile state of the Hawaiian volcanoes and their constant battle with the sea was a major element in Hawaiian mythology, embodied in Pele, the deity of volcanoes. After the arrival of Europeans on the island, in 1880–1881 James Dwight Dana directed the first formal geological study of the hotspot's volcanics, confirming the relationship long observed by the natives. 1912 marked the founding of the Hawaiian Volcano Observatory by volcanologist Thomas Jaggar, initiating continuous scientific observation of the islands. In the 1970s, a mapping project was initiated to gain more information about the complex geology of Hawaii's seafloor.
...
Wikipedia