Easter hotspot

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The Easter hotspot is marked 7 on map. Hotspots.jpg
The Easter hotspot is marked 7 on map.

The Easter hotspot is a volcanic hotspot located in the southeastern Pacific Ocean. The hotspot created the Sala y Gómez Ridge which includes Easter Island and the Pukao Seamount which is at the ridge's young western edge. Easter Island, because of its tectonomagmatic features (low eruptive rate, scattered rift zones, and scarce lateral collapses), represents an end-member type of hotspot volcano in this chain. [1]

Volcano A rupture in the crust of a planetary-mass object that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface

A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.

Hotspot (geology) Volcanic regions thought to be fed by underlying mantle that is anomalously hot compared with the surrounding mantle

In geology, the places known as hotspots or hot spots are volcanic regions thought to be fed by underlying mantle that is anomalously hot compared with the surrounding mantle. Their position on the Earth's surface is independent of tectonic plate boundaries. There are two hypotheses that attempt to explain their origins. One suggests that hotspots are due to mantle plumes that rise as thermal diapirs from the core–mantle boundary. The other hypothesis is that lithospheric extension permits the passive rising of melt from shallow depths. This hypothesis considers the term "hotspot" to be a misnomer, asserting that the mantle source beneath them is, in fact, not anomalously hot at all. Well-known examples include the Hawaii, Iceland and Yellowstone hotspots.

Pacific Ocean Ocean between Asia and Australia in the west, the Americas in the east and Antarctica or the Southern Ocean in the south.

The Pacific Ocean is the largest and deepest of Earth's oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean in the south and is bounded by Asia and Australia in the west and the Americas in the east.

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The hotspot may also be responsible for the formation of the Tuamotu Archipelago, Line Islands, and the chain of seamounts lying in between. [2]

Line Islands chain of eleven atolls and low coral islands in the central Pacific Ocean

The Line Islands, Teraina Islands or Equatorial Islands, is a chain of atolls and coral islands. Kingman Reef is largely submerged and Filippo Reef is shown on some maps, although its existence is doubted. The islands were formed by volcanic activity and are located in the central Pacific Ocean, south of the Hawaiian Islands. The 11 islands stretch for 2,350 kilometres in a northwest–southeast direction, making it one of the longest island chains of the world. Eight of the islands form part of Kiribati, while the remaining three are United States territories grouped with the United States Minor Outlying Islands. Only Kiritimati and Tabuaeran atolls and Teraina Island have a permanent population.

See also

Moai (seamount) The second most westerly submarine volcano in the Easter Seamount Chain

The Moai Seamount is a submarine volcano, the second most westerly in the Easter Seamount Chain or Sala y Gómez ridge. It is east of Pukao seamount and west of Easter Island. It rises over 2,500 metres from the ocean floor to within a few hundred metres of the sea surface. The Moai seamount is fairly young, having developed in the last few hundred thousand years as the Nazca Plate floats over the Easter hotspot.

Related Research Articles

Seamount A mountain rising from the ocean seafloor that does not reach to the waters surface

A seamount is a mountain rising from the ocean seafloor that does not reach to the water's surface, and thus is not an island, islet or cliff-rock. Seamounts are typically formed from extinct volcanoes that rise abruptly and are usually found rising from the seafloor to 1,000–4,000 m (3,300–13,100 ft) in height. They are defined by oceanographers as independent features that rise to at least 1,000 m (3,281 ft) above the seafloor, characteristically of conical form. The peaks are often found hundreds to thousands of meters below the surface, and are therefore considered to be within the deep sea. During their evolution over geologic time, the largest seamounts may reach the sea surface where wave action erodes the summit to form a flat surface. After they have subsided and sunk below the sea surface such flat-top seamounts are called "guyots" or "tablemounts"

Hawaiian–Emperor seamount chain A mostly undersea mountain range in the Pacific Ocean that reaches above sea level in Hawaii.

The Hawaiian–Emperor seamount chain is a mostly undersea mountain range in the Pacific Ocean that reaches above sea level in Hawaii. It is composed of the Hawaiian ridge, consisting of the islands of the Hawaiian chain northwest to Kure Atoll, and the Emperor Seamounts: together they form a vast underwater mountain region of islands and intervening seamounts, atolls, shallows, banks and reefs along a line trending southeast to northwest beneath the northern Pacific Ocean. The seamount chain, containing over 80 identified undersea volcanoes, stretches over 5,800 kilometres (3,600 mi) from the Aleutian Trench in the far northwest Pacific to the Loʻihi seamount, the youngest volcano in the chain, which lies about 35 kilometres (22 mi) southeast of the Island of Hawaiʻi.

Isla Salas y Gómez island of Chile

Isla Salas y Gómez, also known as Isla Sala y Gómez, is a small uninhabited Chilean island in the Pacific Ocean. It is sometimes considered the easternmost point in the Polynesian Triangle.

Meiji Seamount The oldest seamount in the Hawaiian-Emperor seamount chain

Meiji Seamount, named after Emperor Meiji, the 122nd Emperor of Japan, is the oldest seamount in the Hawaiian-Emperor seamount chain, with an estimated age of 82 million years. It lies at the northernmost end of the chain, and is perched at the outer slope of the Kuril-Kamchatka Trench. Like the rest of the Emperor seamounts, it was formed by the Hawaii hotspot volcanism, grew to become an island, and has since subsided to below sea level, all while being carried first north and now northwest by the motion of the Pacific Plate. Meiji Seamount is thus an example of a particular type of seamount known as a guyot, and some publications refer to it as Meiji Guyot.

Poike

Poike is one of three main extinct volcanoes that form Rapa Nui. At 370 metres, it is the island's second highest point after Terevaka.

Rano Kau

Rano Kau is a 324 m (1,063 ft) tall extinct volcano that forms the southwestern headland of Easter Island, a Chilean island in the Pacific Ocean. It was formed of basaltic lava flows in the Pleistocene with its youngest rocks dated at between 150,000 and 210,000 years ago.

Terevaka

Ma′unga Terevaka is the largest, tallest and youngest of three main extinct volcanoes that form Rapa Nui. Several smaller volcanic cones and craters dot its slopes, including a crater hosting one of the island's three lakes, Rano Aroi.

The Pukao Seamount is a submarine volcano, the most westerly in the Easter Seamount Chain or Sala y Gómez ridge. To the east are Moai (seamount) and then Easter Island. It rises over 2,500 metres from the ocean floor to within a few hundred metres of the sea surface. The Pukao Seamount is fairly young, and believed to have developed in the last few hundred thousand years as the Nazca Plate floats over the Easter hotspot.

Hawaii hotspot A volcanic hotspot located near the Hawaiian Islands, in the northern Pacific Ocean

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.

Geology of Chile

The geology of Chile is a characterized by processes linked to subduction such as volcanism, earthquakes and orogeny. The buildings blocks of Chile's geology assembled during the Paleozoic Era. Chile was by then the southwestern margin of the supercontinent Gondwana. In the Jurassic Gondwana begun to split and the ongoing period of crustal deformation and mountain building known as the Andean orogeny begun. In the Late Cenozoic Chile definitely separated from Antarctica, the Andes expienced a great rise accomplained by a cooling climate and the onset of glaciations.

Pitcairn hotspot

The Pitcairn hotspot is a volcanic hotspot located in the south-central Pacific Ocean. Over the past 11 million years, it has formed the Pitcairn-Gambier hotspot chain. It is responsible for creating the Pitcairn Islands and two large seamounts named Adams and Bounty, as well as atolls at Moruroa, Fangataufa and the Gambier Islands. The hotspot is currently located at Adams and Bounty, which are ~60 kilometers East-Southeast of Pitcairn Island.

Nazca Ridge A submarine ridge on the Nazca Plate off the west coast of South America

The Nazca Ridge is a submarine ridge, located on the Nazca Plate off the west coast of South America. This plate and ridge are currently subducting under the South American Plate at a convergent boundary known as the Peru-Chile Trench at approximately 7.7 cm/yr. The Nazca Ridge began subducting obliquely to the collision margin at 11°S, approximately 11.2 Ma, and the current subduction location is 15°S. The ridge is composed of abnormally thick basaltic ocean crust, averaging 18 ±3 km thick. This crust is buoyant, resulting in flat slab subduction under Peru. This flat slab subduction has been associated with the uplift of Pisco Basin and the cessation of Andes volcanism and the uplift of the Fitzcarrald Arch on the South American continent approximately 4 Ma.

Macdonald hotspot hotspot in the Pacific Ocean

The Macdonald hotspot is a volcanic hotspot in the southern Pacific Ocean. The hotspot was responsible for the formation of the Macdonald Seamount, and possibly the Austral-Cook Islands chain. It probably did not generate all of the volcanism in the Austral and Cook Islands as age data imply that several additional hotspots were needed to generate some volcanoes.

Geology of the Pacific Ocean

The Pacific Ocean evolved in the Mesozoic from the Panthalassic Ocean, which had formed when Rodinia rifted apart around 750 Ma. The first ocean floor which is part of the current Pacific Plate began 160 Ma to the west of the central Pacific and subsequently developed into the largest oceanic plate on Earth.

Foundation Seamounts A series of seamounts in the southern Pacific Ocean in a chain which starts at the Pacific-Antarctic Ridge

Foundation Seamounts are a series of seamounts in the southern Pacific Ocean. Discovered in 1992, these seamounts form a 1,350 kilometres (840 mi) long chain which starts from the Pacific-Antarctic Ridge. Some of these seamounts may have once emerged from the ocean.

Rano Rahi is a field of seamounts in the Pacific Ocean. These seamounts in part form a series of ridges on the Pacific Plate pointing away from the neighbouring East Pacific Rise and which were volcanically active until about 230,000 years ago, and possibly even more recently.

Crough Seamount is a seamount in the Pacific Ocean, within the exclusive economic zone of Pitcairn. It rises to a depth of 650 metres (2,130 ft) and is paired with a taller but overall smaller seamount to the east. This seamount has a flat top and probably formed an island in the past. It is about 7-8 million years old, although a large earthquake recorded at its position in 1955 may indicate a recent eruption.

References

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In computing, a Digital Object Identifier or DOI is a persistent identifier or handle used to uniquely identify objects, standardized by the International Organization for Standardization (ISO). An implementation of the Handle System, DOIs are in wide use mainly to identify academic, professional, and government information, such as journal articles, research reports and data sets, and official publications though they also have been used to identify other types of information resources, such as commercial videos.