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Monowai Seamount
Monowai Seamount is a volcanic seamount to the north of New Zealand. It is formed by a large caldera and a volcanic cone just south-southeast from the caldera. The volcanic cone rises to depths of up to but its depth varies with ongoing volcanic activity, including sector collapses and the growth of lava domes. The seamount and its volcanism were discovered after 1877, but only in 1980 was it named "Monowai" after a research ship of the same name. The subduction of the Pacific Plate beneath the Australia Plate has given rise to volcanic and hydrothermal activity on the Kermadec Ridge that Monowai is part of. The volcano is located at the site where the Osbourn Trough and the Louisville seamount chain subduct in the Tonga Trench and this subduction process probably has influenced its volcanism. Monowai is one of the most active volcanoes in the Kermadec volcanic arc, with many eruptions since 1977, and perhaps the most active submarine volcano in the world. Volcanic activity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HMNZS Monowai (A06)
HMNZS ''Monowai'' (A06) was a hydrographic survey vessel of the Royal New Zealand Navy (RNZN). Built in 1960, the ship was originally used as a civilian supply and passenger vessel by the New Zealand Government, under the name GMV ''Moana Roa'', before being acquired by the RNZN in 1974. She was commissioned into the RNZN in 1975 for the voyage to Scotland for conversion and commissioned into the RNZN in October 1977. She remained in RNZN service until April 1998, performing various duties such as coastal surveying, resupply, and surveillance. After being decommissioned she was sold to civilian operators in Britain in 1998 for conversion to a cruise ship, but was found unsuitable for the role and eventually sent to Spanish shipbreakers in 2002. Construction and design The ship was laid down by Grangemouth Dockyard in Scotland in 1960. The ship displaced 3,900 tons at full load, was in length overall and long at the keel, had a beam of and a draught of . Propulsion machinery ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kermadec Islands
The Kermadec Islands ( mi, Rangitāhua) are a subtropical island arc in the South Pacific Ocean northeast of New Zealand's North Island, and a similar distance southwest of Tonga. The islands are part of New Zealand. They are in total area and uninhabited, except for the permanently manned Raoul Island Station, the northernmost outpost of New Zealand. The islands are listed with the New Zealand outlying islands. The islands are an immediate part of New Zealand, but not part of any region or district, but instead an ''Area Outside Territorial Authority''. Toponymy The islands were named after the Breton captain Jean-Michel Huon de Kermadec, who visited the islands as part of the d'Entrecasteaux expedition in the 1790s. The topographic particle "Kermadec" is of Breton origin and is a lieu-dit in Pencran in Finistère where '' ker'' means village, residence and madec a proper name derived from '' mad'' (which means 'good') with the suffix '' -ec'', used to form adjectives in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rumble III
Rumble or Rumbling may refer to: Sounds and vibrations * Rumble (noise), a form of low frequency noise * Rumble, a haptic feedback vibration feature in video game controllers * Rumbling, a quality of a heart murmur * Stomach rumble, or borborygmus, a medical term Places * Rumble, Shetland, an islet group off Whalsay, Scotland, UK * Rumble, Indiana, US * Rumble, West Virginia, US People * Anthony Johnson (fighter), an American mixed martial artist nicknamed Rumble * Dane Rumble (born 1982), New Zealand recording artist * Darren Rumble (Australian rules footballer) (born 1984), Fremantle draftee * Darren Rumble (ice hockey) (born 1969), Canadian ice hockey player and coach * Mark Rumble, British television presenter on '' Studio Disney UK'' * Paul Rumble (born 1969), English footballer * Terry Rumble (born 1942), Australian politician * Tony Rumble (1956–1999), American professional wrestler * Mike Rumbles (born 1956), Scottish politician Arts and entertainment Films a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raoul Island
Raoul Island (''Sunday Island'') is the largest and northernmost of the main Kermadec Islands, south south-west of 'Ata Island of Tonga and north north-east of New Zealand's North Island. It has been the source of vigorous volcanic activity during the past several thousand years that was dominated by dacitic explosive eruptions. The area of the anvil-shaped island, including fringing islets and rocks mainly in the northeast, but also a few smaller ones in the southeast, is . The highest elevation is Moumoukai Peak, at an elevation of . Although Raoul is the only island in the Kermadec group large enough to support settlement, it lacks a safe harbour, and landings from small boats can be made only in calm weather. The island consists of two mountainous areas, one with summits of and , and the other with a summit of , the two separated by a depression which is the caldera of the Raoul volcano. History Evidence from archaeological sites on the northern coast of Raoul Isla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Back-arc
A back-arc basin is a type of geologic basin, found at some convergent plate boundaries. Presently all back-arc basins are submarine features associated with island arcs and subduction zones, with many found in the western Pacific Ocean. Most of them result from tensional forces, caused by a process known as oceanic trench rollback, where a subduction zone moves towards the subducting plate. Back-arc basins were initially an unexpected phenomenon in plate tectonics, as convergent boundaries were expected to universally be zones of compression. However, in 1970, Dan Karig published a model of back-arc basins consistent with plate tectonics. Structural characteristics Back-arc basins are typically very long and relatively narrow, often thousands of kilometers long while only being a few hundred kilometers wide at most. For back-arc extension to form, a subduction zone is required, but not all subduction zones have a back-arc extension feature. Back-arc basins are found in area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submarine Volcano
Submarine volcanoes are underwater vents or fissures in the Earth's surface from which magma can erupt. Many submarine volcanoes are located near areas of tectonic plate formation, known as mid-ocean ridges. The volcanoes at mid-ocean ridges alone are estimated to account for 75% of the magma output on Earth.Martin R. Speight, Peter A. Henderson, "Marine Ecology: Concepts and Applications", John Wiley & Sons, 2013. . Although most submarine volcanoes are located in the depths of seas and oceans, some also exist in shallow water, and these can discharge material into the atmosphere during an eruption. The total number of submarine volcanoes is estimated to be over 1 million (most are now extinct) of which some 75,000 rise more than 1 km above the seabed. Only 119 submarine volcanoes in Earth's oceans and seas are known to have erupted during the last 11,700 years. Hydrothermal vents, sites of abundant biological activity, are commonly found near submarine volcanoes. Effe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Island
Geologically, a high island or volcanic island is an island of volcanic origin. The term can be used to distinguish such islands from low islands, which are formed from sedimentation or the uplifting of coral reefs (which have often formed on sunken volcanos). Definition and origin There are a number of "high islands" that rise no more than above sea level, often classified as "islets or rocks", while some low islands, such as Banaba, Henderson Island, Makatea, Nauru, and Niue, as uplifted coral islands, rise over above sea level. The two types of islands are often found in proximity to each other, especially among the islands of the South Pacific Ocean, where low islands are found on the fringing reefs that surround most high islands. Volcanic islands normally arise above a hotspot. Habitability High islands above a certain size usually have fresh groundwater Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tonga-Kermadec Ridge
The Tonga-Kermadec Ridge is an oceanic ridge in the south-west Pacific Ocean underlying the Tonga-Kermadec island arc. It is the most linear, fastest converging, and most seismically active subduction boundary on Earth, and consequently has the highest density of submarine volcanoes. The Tonga-Kermadec Ridge stretches more than north-northeast from New Zealand's North Island. The Pacific Plate subducts westward beneath the Australian Plate along the ridge. It is divided into two segments, the northern Tonga Ridge and southern Kermadec Ridge, by the Louisville Seamount Chain. On its western side, the ridge is flanked by two back-arc basins, the Lau Basin and Havre Trough, that began opening at 6 and 2 Ma respectively. Together with these younger basins the ridge forms the eastward-migrating, 100 Ma-old Lau-Tonga-Havre-Kermadec arc/back-arc system or complex. The extension in the Lau-Havre basin results in a higher rate of subduction than convergence along the Au ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tonga
Tonga (, ; ), officially the Kingdom of Tonga ( to, Puleʻanga Fakatuʻi ʻo Tonga), is a Polynesian country and archipelago. The country has 171 islands – of which 45 are inhabited. Its total surface area is about , scattered over in the southern Pacific Ocean. As of 2021, according to Johnson's Tribune, Tonga has a population of 104,494, 70% of whom reside on the main island, Tongatapu. The country stretches approximately north-south. It is surrounded by Fiji and Wallis and Futuna (France) to the northwest; Samoa to the northeast; New Caledonia (France) and Vanuatu to the west; Niue (the nearest foreign territory) to the east; and Kermadec (New Zealand) to the southwest. Tonga is about from New Zealand's North Island. First inhabited roughly 2,500 years ago by the Lapita civilization, Tonga's Polynesian settlers gradually evolved a distinct and strong ethnic identity, language, and culture as the Tongan people. They were quick to establish a powerful footing acr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ROPOS
ROPOS ("Remotely Operated Platform for Ocean Science") is an ROV used primarily for scientific research. It was originally built in Vancouver by International Submarine Engineering and purchased by the Canadian federal government. The same government program also operated the '' Pisces IV'' crewed submersible, now in Hawaii being run by the Hawai'i Undersea Research Laboratory (HURL) who found the long-lost two-man Japanese sub which heralded the attack on Pearl Harbor. The funding for the Canadian submersible program eventually dried up, but by that time the user group had been established and long term experiments put in place on the sea floor. The Canadian Scientific Submersible Facility (CSSF) was formed and leased ROPOS from the government for several years before finally purchasing the ROV a few years ago. In 2005 the vehicle was extensively rebuilt and now boasts a thru-frame lift capability (see below). The ROV is controlled and powered from a surface vessel. Electrical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pisces V
''Pisces V'' is a type of manned submersible ocean exploration device, powered by battery, and capable of operating to depths of , a depth that is optimum for use in the sea waters around the Hawaiian Islands. It is used by scientists to explore the deep sea around the underwater banks in the main Hawaiian Islands, as well as the underwater features and seamounts in the Northwestern Hawaiian Islands, specifically around Kamaʻehuakanaloa Seamount (formerly Loihi). In 1973, ''Pisces V'' took part in the rescue of Roger Mallinson and Roger Chapman, who were trapped on the seabed in ''Pisces V''s sister submersible '' Pisces III''. In August 2002, ''Pisces V'' and her sister ''Pisces IV'' discovered a World War II Japanese midget submarine outside of Pearl Harbor which had been sunk by the destroyer in the first American shots fired in World War II. In 2011, marine scientists from HURL celebrated the 1,000 dives of ''Pisces V'' and ''Pisces IV''. Uses The advantage of having t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pumice Raft
A pumice raft is a floating raft of pumice created by some eruptions of submarine volcanoes or coastal subaerial volcanoes. Biologists suggest that animals and plants have migrated from island to island on pumice rafts. Pumice rafts have unique characteristics such as the highest surface-area-to-volume ratio known for any rock type, long term flotation and beaching in the tidal zone, exposure to a variety of conditions, including dehydration, and an ability to absorb many potentially advantageous elements/compounds. For at least these reasons, astrobiologists have hypothetically proposed pumice rafts as an ideal substrate for the origin of life. Notable examples Pumice rafts drifted to Fiji in 1979 and 1984 from eruptions around Tonga, and some were reportedly wide. Volcanic activity in the South Pacific near Tonga on August 12, 2006 caused the emergence of a new island. The crew of the ''Maiken'', a yacht that had left the northern Tongan islands group of Vava'u in August ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
