Resolution Guyot (formerly known as Huevo) is a guyot/tablemount in the underwater Mid-Pacific Mountains, Pacific Ocean. It is a circular flat mountain that rises 500 metres (1,600 ft) above the seafloor to a depth of about 1,320 metres (4,330 ft), with a 35 kilometres (22 mi) wide summit platform. The Mid-Pacific Mountains and thus also Resolution Guyot lie west of Hawaii and northeast of the Marshall Islands but at the time of its formation it was located in the Southern Hemisphere.
In marine geology, a guyot, also known as a tablemount, is an isolated underwater volcanic mountain (seamount) with a flat top more than 200 m (660 ft) below the surface of the sea. The diameters of these flat summits can exceed 10 km (6.2 mi). Guyots are most commonly found in the Pacific Ocean, but they have been identified in all the oceans except the Arctic Ocean.
The Mid-Pacific Mountains (MPM) is a large oceanic plateau located in the central North Pacific Ocean or south of the Hawaiian–Emperor seamount chain. Of volcanic origin and Mesozoic in age, it is located on the oldest part of the Pacific Plate and rises up to 2 km (1.2 mi) above the surrounding ocean floor and is covered with several layers of thick sedimentary sequences that differs from those of other plateaux in the North Pacific. c. 50 seamounts are distributed over the MGM. Some of the highest points in the range are above sea level which include Wake Island and Marcus Island.
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.
It was probably formed by a hotspot in what is present-day French Polynesia before plate tectonics moved it to its present-day location. A number of hotspots such as the Easter hotspot, the Marquesas hotspot, the Pitcairn hotspot and the Society hotspot may have been involved in the formation of Resolution Guyot. Volcanic activity has been dated to have occurred 107-129 million years ago and formed a volcanic island. Subsequently erosion flattened the island and carbonate deposition commenced, forming an atoll-like structure and a carbonate platform.
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.
French Polynesia is an overseas collectivity of the French Republic and the only overseas country of France. It is composed of 118 geographically dispersed islands and atolls stretching over an expanse of more than 2,000 kilometres (1,200 mi) in the South Pacific Ocean. Its total land area is 4,167 square kilometres (1,609 sq mi).
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, represents an end-member type of hotspot volcano in this chain.
The platform emerged above sea level at some time between the Albian and Turonian ages before eventually drowning for reasons unknown between the Albian and the Maastrichtian. Thermal subsidence lowered the drowned seamount to its present depth. After a hiatus, sedimentation commenced on the seamount and led to the deposition of manganese crusts and pelagic sediments, some of which were later modified by phosphate.
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± 0.9 Ma. The Albian is preceded by the Aptian and followed by the Cenomanian.
The Turonian is, in the ICS' geologic timescale, the second age in the Late Cretaceous epoch, or a stage in the Upper Cretaceous series. It spans the time between 93.9 ± 0.8 Ma and 89.8 ± 1 Ma. The Turonian is preceded by the Cenomanian stage and underlies the Coniacian stage.
The Maastrichtian is, in the ICS geologic timescale, the latest age of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned the interval from. The Maastrichtian was preceded by the Campanian and succeeded by the Danian.
Resolution Guyot was formerly informally known as Huevo Guyotbefore it was renamed after the drilling ship JOIDES Resolution during Leg 143 of the Ocean Drilling Program in 1992. During that Leg, JOIDES Resolution took drill cores from Resolution Guyot called 866A, 867A and 867B; 866A was drilled on the summit platform of Resolution Guyot, 867B (and the unsuccessful drilling attempt 867A) on the platform margin and 868A on a terrace outside of the platform.
The riserless research vessel JOIDES Resolution, often referred to as the JR, is one of the scientific drilling ships used by the International Ocean Discovery Program (IODP), an international, multi-drilling platform research program. The JR was previously the main research ship used during the Ocean Drilling Program (ODP) and was used along with the Japanese drilling vessel Chikyu and other mission-specific drilling platforms throughout the Integrated Ocean Drilling Program. She is the successor of Glomar Challenger.
The Ocean Drilling Program (ODP) was a multinational effort to explore and study the composition and structure of the Earth's oceanic basins. ODP, which began in 1985, was the successor to the Deep Sea Drilling Project initiated in 1968 by the United States. ODP was an international effort with contributions of Australia, Germany, France, Japan, the United Kingdom and the ESF Consortium for Ocean Drilling (ECOD) including 12 further countries. The program used the drillship JOIDES Resolution on 110 expeditions (legs) to collect about 2000 deep sea cores from major geological features located in the ocean basins of the world. Drilling discoveries led to further questions and hypotheses, as well as to new disciplines in earth sciences such as the field of paleoceanography. In 2004 ODP transformed into the Integrated Ocean Drilling Program (IODP).
Resolution Guyot is part of the western Mid-Pacific Mountains, which are located west of Hawaii and north-northeast of the Marshall Islands.Unlike conventional island chains in the Pacific Ocean, the Mid-Pacific Mountains are a group of oceanic plateaus with guyots (also known as tablemounts ) that become progressively younger towards the east. Other guyots in the Mid-Pacific Mountains are Sio South, Darwin, Thomas, Heezen, Allen, Caprina, Jacqueline and Allison.
Hawaii is the 50th and most recent state to have joined the United States, having received statehood on August 21, 1959. Hawaii is the only U.S. state located in Oceania, the only U.S. state located outside North America, and the only one composed entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean.
The Marshall Islands, officially the Republic of the Marshall Islands, are an island country and a United States associated state near the equator in the Pacific Ocean, slightly west of the International Date Line. Geographically, the country is part of the larger island group of Micronesia. The country's population of 53,158 people is spread out over 29 coral atolls, comprising 1,156 individual islands and islets.
An oceanic or submarine plateau is a large, relatively flat elevation that is higher than the surrounding relief with one or more relatively steep sides.
The seamount is about 500 metres (1,600 ft) high and rises from a raised seafloor to a depth of about 1,320 metres (4,330 ft). At a depth of 1,300–1,400 metres (4,300–4,600 ft) it is capped off by a 35 kilometres (22 mi) wide rather flat and roughly circular summit platform with a 25 metres (82 ft) high rim and a moat inside of this rim. At the margin of the platform, structures interpreted as sea cliffs or wave cut terraces have been found; at one site there is an about 200 metres (660 ft) wide terrace surmounted by a 25 metres (82 ft) high cliff. Pinnacles and depressions dot the surface platform. The surface of the platform consists of limestone that is partially covered by pelagic sediments, underwater cameras have shown the presence of rock slabs covered by ferromanganese crusts.
A wave-cut platform, shore platform, coastal bench, or wave-cut cliff is the narrow flat area often found at the base of a sea cliff or along the shoreline of a lake, bay, or sea that was created by erosion. Wave-cut platforms are often most obvious at low tide when they become visible as huge areas of flat rock. Sometimes the landward side of the platform is covered by sand, forming the beach, and then the platform can only be identified at low tides or when storms move the sand.
Limestone is a sedimentary rock which is often composed of the skeletal fragments of marine organisms such as coral, foraminifera, and molluscs. Its major materials are the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO3).
The guyot rises from a seafloor of Jurassic age(201.3 ± 0.2 - ca. 145 million years ago ) that might be as much as 154 million years old. Terrigenous sediments found on the seafloor around Resolution Guyot probably originated at the guyot when it was still an island, and carbonate sediments swept away from the guyot ended up on the surrounding seafloor.
The Pacific Ocean seafloor contains many guyots of Mesozoic age (251.902 ± 0.3 - 66 million years ago) that developed in unusually shallow seas. These are submarine mountains which are characterized by a flat top and usually the presence of carbonate platforms that rose above the sea surface during the middle Cretaceous (ca. 145 - 66 million years ago ). While there are some differences to present-day reef systems, many of these seamounts were formerly atolls, which today still exist. All these structures originally formed as volcanoes in the Mesozoic ocean. Fringing reefs may have developed on the volcanoes, which then became barrier reefs as the volcano subsided and turned into an atoll, and which surround a lagoon or tidal flat. The crust underneath these seamounts tends to subside as it cools, and thus the islands and seamounts sink. Continued subsidence balanced by upward growth of the reefs led to the formation of thick carbonate platforms. Sometimes volcanic activity continued even after the formation of the atoll or atoll-like structure, and during episodes where the platforms rose above sea level erosional features such as channels and blue holes developed.
The formation of many such seamounts has been explained with the hotspot theory, which describes the formation of chains of volcanoes which get progressively older along the length of the chain,with an active volcano only at one end of the system. This volcano lies on a spot of the lithosphere heated from below; as the plate moves the volcano is moved away from the heat source and volcanic activity ceases, producing a chain of volcanoes that get progressively older away from the currently active one. Candidate hotspots involved in the genesis of Resolution Guyot are the Easter hotspot, the Marquesas hotspot, the Society hotspot and in some plate reconstructions the Pitcairn hotspot although not all plate reconstructions point at a presently active hotspot. More than one hotspot may have influenced the growth of Resolution Guyot, and it and Allison Guyot may have been formed by the same hotspot(s). The entire Mid-Pacific Mountains may be the product of such a hotspot as well.
Rocks found at Resolution Guyot include basalt of the volcano and carbonates deposited in shallow-water conditions on the volcano.Minerals found in the basalt are alkali feldspar, clinopyroxene feldspar, ilmenite, magnetite, olivine, plagioclase, spinel and titanomagnetite; the olivine, plagioclase and pyroxenes form phenocrysts. Alteration has produced analcime, ankerite, calcite, clay, hematite, iddingsite, pyrite, quartz, saponite, serpentine and zeolite. The basalts represent an alkaline intraplate suite, earlier trachybasalts containing biotite have been recovered as well.
The carbonates occur in the form of boundstone,carbonate hardgrounds, floatstone, grainstone, grapestone, oncoids, ooliths, packstone, peloids, rudstones, spherulites, and wackestones. Alteration has formed calcite, dolomite, quartz through silicification and vugs. Dolomite alteration is particularly widespread in modern atolls and a number of different processes have been invoked to explain it, such as geothermally driven convection of seawater. Dissolved fossils and traces of animal burrows are found in some rock sequences with bioturbation traces widespread. Barite needles, calcretes, cementation forms that developed under the influence of freshwater, desiccation cracks and ferromanganese occurrences as dendrites have also been found.
Organic materialshave been found in rock samples from Resolution Guyot and appear to be mainly of marine origin. However, some of the organic matter comes from microbial mats and vegetated islands, including wood and plant fragments.
Clays found on Resolution Guyot have been characterized as chlorite, glauconite, hydromica,illite, kaolinite, saponite and smectite. Claystones have also been found. Most clays have been found in the lower carbonate sequence, while the upper parts mostly lack clay deposits. Some of the clays may originate from younger volcanoes east of Resolution Guyot.
Apatite has formed through phosphate modification of exposed rocks underwater.Other minerals include anhydrite, celestite, goethite, gypsum, limonite and pyrite which is also present in the carbonates. Finally, mudstones have been found.
Radiometric dating has been carried out on volcanic rocks from Resolution Guyot but the basalts are heavily altered and the dates thus uncertain. Potassium-argon dating has yielded ages of 107-125 million years ago while argon-argon dating has yielded ages of 120-129 million years ago.Magnetization data indicate that Resolution Guyot was located in the Southern Hemisphere when it formed.
Eruptions at Resolution Guyot formed a pile of volcanic rocks, from which a 125 metres (410 ft) thick sequence has been drilled. It consists of stacks of lava flows, each of which is about 10 metres (33 ft) thick, but there are also breccias , intrusions and sills. The lava flows appear to have been emplaced years apart from each other. Resolution Guyot was also hydrothermally active. This volcanic activity over 1-2 million years generated a volcanic island. Volcanic activity took place in a tropical or subtropical environment and between eruptions weathering, soil formation and potentially mass failures generated layers of clay, rock debris and alteration products such as laterite. Erosion eventually flattened the volcanic island to form a platform.
Between the Hauterivian (ca. 132.9 - ca. 129.4 million years ago 1,619 metres (5,312 ft) of carbonate was deposited on the volcanic structure, eventually completely burying it during the Albian. About 14 individual sequences of carbonates have been identified in drill cores. The carbonate sedimentation probably began in the form of shoals surrounding a volcanic island and lasted for about 35 million years, accompanied by perhaps 0.046 millimetres per year (0.0018 in/year) of subsidence. It is likely that the present-day carbonate platform contains only a fraction of the originally deposited carbonate, with most of the carbonate having disappeared. During this time, Resolution Guyot underwent little latitudinal plate motion; from the magnetization it appears that the seamount was stably located at about 13° southern latitude between the Hauterivian and Aptian.) and Albian (ca. 113 - 100.5 million years ago ), about
The exact structure of the Resolution Guyot carbonate platform cannot be reconstructed as only small parts thereof have been studied, but some statements can be made.The Resolution platform was surrounded by barrier islands but featured only a few reefs; unlike present-day atolls which were rimmed by reefs Cretaceous platforms were rimmed by sand shoals and on Resolution Guyot drill cores into the rim have only found sediment accumulations and no reefs. Analysis of the carbonate layers has identified that a number of environments existed on the platform, including swash beaches, lagoons, marshes, mudflats, sabkhas, sand bars and washover fans from storms; at times there were also open-marine conditions. Some environments on Resolution Guyot were hypersaline at times, probably implying that they had only limited water exchange with the surrounding ocean. Islands formed from sand bars, resembling these of the Bahama Banks. Records from Hole 866A indicate that settings at a given site were not stable over longer time periods.
The Cretaceous Apulian Carbonate Platform in Italy, the Urgonian Formation in France have been compared to the Resolution Guyot carbonates. All these platforms were located in Tethyan seasand several formations in these three carbonate environments are correlated; for example, the fauna identified on Resolution Guyot resembles that from other Northern Hemisphere platforms. Analogies also exist to platforms in Venezuela.
Water temperatures in the early Aptian (ca. 125 - ca. 113 million years ago 30–32 °C (86–90 °F). The platform was exposed to southeasterly trade winds which left the northern side of the platform sheltered from waves, except from storm-generated waves. These waves, wind and tidal currents acted to shift sediments around on the platform. Storms formed beaches on the platform, although the interior parts of the platform were effectively protected by the surrounding shoals from storm influence. Some patterns in the sedimentation indicate a seasonal climate. When the climate was arid, gypsum deposition took place.) are inferred to have been
Through the history of the Resolution Guyot platform sea level variations occurred and led to characteristic changes in the accumulating carbonate sediments,with typical facies and sequences forming in the carbonate layers. The Selli event, an oceanic anoxic event, is recorded at Resolution Guyot as is the Faraoni event. The Selli event left a black shale layer and may have caused a temporary interruption in carbonate accumulation before the platform recovered. During the Albian-Aptian some carbonates became dolomites.
Life on Resolution Guyot included algae including both green algae and red algae, bivalvesincluding rudists, bryozoans, corals, echinoderms, echinoids, foraminifers, gastropods, ostracods, oysters, serpulid worms, sponges and stromatolithes. Rudists and sponges have been identified as bioherm builders on Resolution Guyot; rudist families found on Resolution include caprinidae of the genus Caprina , coalcomaninae, monopleuridae and requieniidae. Well developed microbial mats grew in some places. Plant remnants have been found in the carbonate sediments, probably reflecting the existence of vegetation-covered islands on the Resolution Guyot platform. Vegetation probably occurred in swamps and marshes as well.
During the Albian to Turonian (93.9 - 89.8 ± 0.3 million years ago 100 metres (330 ft)- 160 metres (520 ft). This uplift episode at Resolution Guyot is part of an episode of more general tectonic changes in the Pacific Ocean, with a general uplift of the ocean floor and tectonic stress changes at the ocean margins. This tectonic event has been explained by a major change in mantle convection in the middle Cretaceous pushing the ocean floor upward and sideward.), the carbonate platform rose above the sea by about
When Resolution Guyot rose above sea level, karst processes began to impact the platform.The platform became irregular and part of it was eroded away; carbonate pinnacles, cavities, caverns containing speleothems and sinkholes formed. At this stage, Resolution Guyot would have resembled a makatea island. This karstic episode did not last for long, perhaps several hundred thousand years, but structures left by the karstic phase such as sinkholes and carbonate pinnacles can still be seen on the surface platform of Resolution Guyot. During periods of emergence, freshwater flowed through and modified the carbonates.
Resolution Guyot drowned either about 99 ± 2 million years agoor during the Maastrichtian (72.1 ± 0.2 to 66 million years ago ), although a hiatus in shallow carbonate deposition appears to date back to the Albian that may reflect a long pause in deposition or increased erosion. The end Albian period was characterized by widespread cessation of carbonate sedimentation across the western Pacific. It is possible that carbonate sedimentation later continued until Campanian (83.6 ± 0.2 - 72.1 ± 0.2 million years ago )-Maastrichtian times. The platform was certainly submerged by Pliocene (5.333 - 2.58 million years ago ) times.
A number of other carbonate platforms in the Pacific drowned especially at the end of the Albian,for unknown reasons; among the proposed mechanisms are overly nutrient rich or turbid waters, the disappearance of reef-forming species and a subsequent failure of them to return, and overly fast sea level rise. Resolution Guyot was never far enough south to end up beyond the Darwin point at which carbonate deposition stops. The Resolution Guyot platform rose above sea level before the drowning, and there is no indication that carbonate deposition recommenced when the platform subsided; similarly other Mid-Pacific Mountains emerged before drowning. There is disagreement about whether Resolution Guyot was close enough to the equator and nutrient rich equatorial waters to drown at the time when carbonate sedimentation ceased.
After the drowning, crusts formed by ferromanganese and by phosphate-modified rocks developed on exposed surfaces at Resolution Guyot.Several different layers of phosphate modification have been observed during the Albian alone and this process may have begun when the platform was still active; water within the rocks may have triggered phosphatization at this stage. The ferromanganese deposition probably only began in the Turonian-Maastrichtian, when the seamount had subsided to a sufficient depth. Manganese-encrusted Cretaceous limestones have been found within the pelagic sediments.
As at other guyots in the Pacific Ocean 7.5 metres (25 ft) in Hole 866B and consist of a Quaternary (last 2.58 million years ), a thin early Pleistocene (2.58 - 0.0117 million years ago ) and a thick Pliocene layer. Some of the sediments take the form of pelagic limestones. In Paleogene (66 to 23.03 million years ago ) sediments ostracods have been found.pelagic sedimentation commenced later; the foraminifera fossils indicate an age of Maastrichtian to Pliocene for such sediments. These sediments reach thicknesses of
Already during the Aptian and Albian, some carbonates had dissolved and were replaced by dolomite. Around 24 million years ago at the Paleogene-Neogene (23.02 - 2.58 million years ago) boundary, a second pulse of dolomite formation took place; perhaps sea level changes associated with global climate change triggered this second pulse. The formation of the dolomites was probably aided by the fact that seawater can percolate through Resolution Guyot.
The Kerguelen Plateau is an oceanic plateau and a large igneous province (LIP) located on the Antarctic Plate, in the southern Indian Ocean. It is also a microcontinent and submerged continent. It is about 3,000 km (1,900 mi) to the southwest of Australia and is nearly three times the size of Japan. The plateau extends for more than 2,200 km (1,400 mi) in a northwest–southeast direction and lies in deep water.
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.
Arago hotspot is a hotspot in the Pacific Ocean, presently located below the Arago seamount close to the island of Rurutu, French Polynesia.
Wōdejebato is a Cretaceous guyot or tablemount in the northern Marshall Islands, Pacific Ocean. Wōdejebato is probably a shield volcano and is connected through a submarine ridge to the smaller Pikinni Atoll 74 kilometres (46 mi) southeast of the guyot; unlike Wōdejebato, Pikinni rises above sea level. The seamount rises for 4,420 metres (14,500 ft) to 1,335 metres (4,380 ft) depth and is formed by basaltic rocks. The name Wōdejebato refers to a sea god of Pikinni.
Limalok is a Cretaceous-Paleocene guyot/tablemount in the southeastern Marshall Islands, one of a number of seamounts in the Pacific Ocean. It was probably formed by a volcanic hotspot in present-day French Polynesia. Limalok lies southeast of Mili Atoll and Knox Atoll, which rise above sea level, and is joined to each of them through a volcanic ridge. It is located at a depth of 1,255 metres (4,117 ft) and has a summit platform with an area of 636 square kilometres (246 sq mi).
Lo-En or Hess is an Albian-Campanian guyot in the Marshall Islands. One among a number of seamounts in the Pacific Ocean, it was probably formed by a hotspot in what is present-day French Polynesia. Limalok lies southeast of Eniwetok which rise above sea level and Lo-En is almost connected to it through a ridge.
Ruwitūn̄tūn̄ is a guyot in the Pacific Ocean which reaches a depth of 1,215 metres (3,986 ft) below sea level. It is capped off with a summit platform covered in sediments and some volcanic pinnacles with craters. Basaltic rocks have been found on Ruwitūn̄tūn̄.
MIT Guyot is a guyot in the Pacific Ocean that rises to a depth of 1,323 metres (4,341 ft). It has a 20-kilometre-long (12 mi) summit platform and formed during the Cretaceous in the region of present-day French Polynesia through volcanic eruptions.
Takuyo-Daisan is a guyot in the Western Pacific Ocean off Japan. It is 1,409 metres (4,623 ft) deep and has a square-shaped flat top surrounded by a perimeter ridge. Several other seamounts lie nearby.
Ioah Guyot is a seamount in the Pacific Ocean, close to the Marshall Islands. Part of the Magellan Seamounts, it is a shield volcano that has erupted alkali basalt and hawaiite 87 million years ago, but may have continued erupting into the Miocene. During the Cretaceous, reefs developed on the guyot.
Ita Mai Tai is a Cretaceous-early Cenozoic seamount northwest of the Marshall Islands and north of Micronesia. One among a number of seamounts in the Pacific Ocean, it is part of the Magellan Seamounts which may have a hotspot origin although Ita Mai Tai itself may not have formed on a hotspot.
The Rarotonga hotspot is a volcanic hotspot in the southern Pacific Ocean. The hotspot was responsible for the formation of Rarotonga and some volcanics of Aitutaki.
Horizon Guyot is a presumably Cretaceous guyot/tablemount in the Mid-Pacific Mountains, Pacific Ocean. It is an over 300 kilometres (190 mi) long elongated ridge that stretches in northeast-southwest direction and has two flat tops; it rises 4.3 kilometres (2.7 mi) to a minimum depth 1,443 metres (4,734 ft). The Mid-Pacific Mountains and thus also Horizon Guyot lie west of Hawaii and northeast of the Line Islands.
Allison Guyot is a tablemount (guyot) in the underwater Mid-Pacific Mountains, Pacific Ocean. It is a trapezoidal flat mountain rising 1,500 metres above the seafloor, with a 35 by 70 kilometres wide summit platform. The Mid-Pacific Mountains lie west of Hawaii and northeast of the Marshall Islands, but at the time of their formation were located in the Southern Hemisphere.
Darwin Guyot is a volcanic underwater mountain top, or guyot, in the Mid-Pacific Mountains between the Marshall Islands and Hawaii. Named after Charles Darwin, it rose above sea level more than 118 million years ago during the early Cretaceous period to become an atoll, developed rudist reefs, and then drowned, perhaps as a consequence of sea level rise. The flat top of Darwin Guyot now rests 1,266 metres (4,154 ft) below sea level.
Takuyo-Daini is a seamount in the Pacific Ocean.
Ujlān volcanic complex is a group of seamounts in the Marshall Islands. The complex consists of the seamounts Ļajutōkwa, Ļalibjet, Likelep, Ļotāb and Ujlān which with a minimum depth of 1,250 metres (4,100 ft) is the shallowest part of the complex; sometimes Ujelang Atoll is also considered to be a part of the complex; Eniwetok atoll and Lo-En seamount form a cluster together with this volcanic complex.
Vlinder Guyot is a guyot in the Western Pacific Ocean. It rises to a depth of 1,500 metres (4,900 ft) and has a flat top covering an area of 40 by 50 kilometres. On top of this flat top lie some volcanic cones, one of which rises to a depth of 551 metres (1,808 ft) below sea level. Vlinder Guyot has noticeable rift zones, including an older and lower volcano to the northwest and Oma Vlinder seamount south.