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Pyroclastic Shield
In volcanology, a pyroclastic shield or ignimbrite shield is an uncommon type of shield volcano. Unlike most shield volcanoes, pyroclastic shields are formed mostly of pyroclastic and highly explosive eruptions rather than relatively fluid basaltic lava issuing from vents or fissures on the surface of the volcano. They typically display low-angle flank slopes and often have a central caldera caused by large eruptions. Lava is commonly extruded after explosive activity has ended. The paucity of associated Plinian fall deposits indicates that pyroclastic shields are characterized by low Plinian columns. Pyroclastic shields are commonly known to form in the Central Andes of South America, as well as in Melanesia (the island of Bougainville alone has two). There are also pyroclastic shields in Africa, such as Emi Koussi in Chad. Examples * Ambrym, Vanuatu * Apoyeque, Nicaragua * Masaya, Nicaragua * Billy Mitchell, Bougainville, Papua New Guinea * Emi Koussi, Chad * Laguna Colora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emi Koussi-Tibesti Mountains-Chad
EMI Group Limited (originally an initialism for Electric and Musical Industries, also referred to as EMI Records Ltd. or simply EMI) was a British Transnational corporation, transnational Conglomerate (company), conglomerate founded in March 1931 in London. At the time of its break-up in 2012, it was the fourth largest Corporate group, business group and record label conglomerate in the music industry, and was one of the "Big Four" record companies (now the "Record label#Major labels, Big Three"). Its labels included EMI Records, Parlophone, Virgin Records, and Capitol Records, which are now owned by other companies. EMI was listed on the London Stock Exchange, and was also once a constituent of the FTSE 100 Index, but faced financial problems and US$4 billion in debt, leading to its acquisition by Citigroup in February 2011. Citigroup's ownership was temporary, as EMI announced in November 2011 that it would sell its music arm to Vivendi's Universal Music Group for $1.9&n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ambrym
Ambrym is a volcanic island in Malampa Province in the archipelago of Vanuatu. Volcanic activity on the island includes lava lakes in two craters near the summit. Etymology Ambrym (also known as ''Ambrin'', ''"ham rim"'' in the Ranon language) was allegedly named by Captain Cook, who is said to have anchored off there in 1774. In fact, his expedition never touched Ambrym. Geography Located near the center of the Vanuatuan archipelago, Ambrym is roughly triangular in shape, about wide. With of surface area, it is the fifth largest island in the country. The summit at the centre of the island is dominated by a desert-like caldera, which covers an area of . With the exception of human settlements, the rest of the island is covered by a dense jungle. Important Bird Area The western part of the island, comprising 17,605 ha of forest, together with gardens around habitation, has been recognised as an Important Bird Area (IBA) by BirdLife International because it supports ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Britain
New Britain ( tpi, Niu Briten) is the largest island in the Bismarck Archipelago, part of the Islands Region of Papua New Guinea. It is separated from New Guinea by a northwest corner of the Solomon Sea (or with an island hop of Umboi the Dampier and Vitiaz Straits) and from New Ireland by St. George's Channel. The main towns of New Britain are Rabaul/Kokopo and Kimbe. The island is roughly the size of Taiwan. While the island was part of German New Guinea, it was named Neupommern ("New Pomerania"). In common with most of the Bismarcks it was largely formed by volcanic processes, and has active volcanoes including Ulawun (highest volcano nationally), Langila, the Garbuna Group, the Sulu Range, and the volcanoes Tavurvur and Vulcan of the Rabaul caldera. A major eruption of Tavurvur in 1994 destroyed the East New Britain provincial capital of Rabaul. Most of the town still lies under metres of ash, and the capital has been moved to nearby Kokopo. Geography New Britain e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rabaul Caldera
The Rabaul caldera, or Rabaul Volcano, is a large volcano on the tip of the Gazelle Peninsula in East New Britain, Papua New Guinea, and derives its name from the town of Rabaul inside the caldera. The caldera has many sub-vents, Tavurvur being the most well known for its devastating eruptions over Rabaul. The outer flanks of the highest peak, a 688-metre-high asymmetrical pyroclastic shield, are formed by thick pyroclastic flow deposits. There is no sign of a pyroclastic shield along the rim of the caldera, making the location likely underwater, on the caldera's floor. Tavurvur, a stratovolcano and a sub-vent of the caldera, is the most visibly active, continuously throwing ash. In 1994 it, and nearby Vulcan, erupted and devastated Rabaul; however, due to planning for such a catastrophe, the townsfolk were prepared and only five people were killed. One of the deaths was caused by lightning, a feature of volcanic ash clouds. In 1937, Vulcan and Tavurvur erupted simultaneously, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chile
Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east and the Pacific Ocean to the west. Chile covers an area of , with a population of 17.5 million as of 2017. It shares land borders with Peru to the north, Bolivia to the north-east, Argentina to the east, and the Drake Passage in the far south. Chile also controls the Pacific islands of Juan Fernández, Isla Salas y Gómez, Desventuradas, and Easter Island in Oceania. It also claims about of Antarctica under the Chilean Antarctic Territory. The country's capital and largest city is Santiago, and its national language is Spanish. Spain conquered and colonized the region in the mid-16th century, replacing Inca rule, but failing to conquer the independent Mapuche who inhabited what is now south-central Chile. In 1818, after declaring in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loloru
Loloru is a pyroclastic shield volcano located in the southern region of Bougainville Island, within the Autonomous Region of Bougainville of northeastern Papua New Guinea. The volcano's summit consists of two nested calderas, with an andesitic lava dome. Lake Loloru Lake Loloru is a crescent-shaped volcanic crater lake covering within the volcano caldera. It is a sacred place of South Bougainvillians, who traditionally believe the souls of their dead go here upon death. See also * * List of volcanoes in Papua New Guinea This is a list of active and extinct volcanoes in Papua New Guinea. New Guinea Admiralty Islands Bougainville D'Entrecasteaux Islands New Britain New Ireland Offshore islands References * Volcanoes of the World Ext ... References * Volcanoes of Bougainville Island Lakes of Papua New Guinea Volcanic crater lakes Geography of the Autonomous Region of Bougainville Mountains of Papua New Guinea Pyroclastic shie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bolivia
, image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square patchwork with the (top left to bottom right) diagonals forming colored stripes (green, blue, purple, red, orange, yellow, white, green, blue, purple, red, orange, yellow, from top right to bottom left) , other_symbol = , other_symbol_type = Dual flag: , image_coat = Escudo de Bolivia.svg , national_anthem = " National Anthem of Bolivia" , image_map = BOL orthographic.svg , map_width = 220px , alt_map = , image_map2 = , alt_map2 = , map_caption = , capital = La Paz Sucre , largest_city = , official_languages = Spanish , languages_type = Co-official languages , languages ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laguna Colorada (caldera)
Laguna Colorada is an ignimbrite shield of the Altiplano-Puna volcanic complex at an altitude of in the Potosi Department of Bolivia. Laguna Colorada is a wide ignimbrite shield that was formerly also known as Panizos (not to be confused with Cerro Panizos. The shield is not clearly associated with a caldera but appears to contain a sag structure. The ignimbrite field is bordered by the Laguna Colorada to the west, Cerro Torque in the north and Quetena to the east; Laguna Colorada is also the origin of the name of the shield. Likewise, the "Tatio formation" at El Tatio originates from eruptions at Laguna Colorada; the 700,000 years old Tatio ignimbrite however is considered to be separate. An older ignimbrite was erupted 2.21±0.05 million years ago. An ignimbrite is associated with Laguna Colorada. This ignimbrite was erupted 1.98 million years ago and has a volume of dense rock equivalent, covering a surface of about . Several fall deposits occur both within and below th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papua New Guinea
Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country in Oceania that comprises the eastern half of the island of New Guinea and its offshore islands in Melanesia (a region of the southwestern Pacific Ocean north of Australia). Its capital, located along its southeastern coast, is Port Moresby. The country is the world's third largest island country, with an area of . At the national level, after being ruled by three external powers since 1884, including nearly 60 years of Australian administration starting during World War I, Papua New Guinea established its sovereignty in 1975. It became an independent Commonwealth realm in 1975 with Elizabeth II as its queen. It also became a member of the Commonwealth of Nations in its own right. There are 839 known languages of Papua New Guinea, one of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Billy Mitchell (volcano)
Billy Mitchell is a pyroclastic shield in the central part of the island of Bougainville, just north-east of the Bagana Volcano in Papua New Guinea. It is a small pyroclastic shield truncated by a 2 km wide caldera filled by a crater lake. It is named after Billy Mitchell, a 20th-century United States Army general who is regarded as the father of the United States Air Force. The last two major eruptions were in 1580 AD ± 20 years and about 1030 AD. They were among the largest Holocene eruptions in Papua New Guinea. Both were explosive eruptions with a Volcanic Explosivity Index of at least 5. The 1580 AD ± 20 years eruption produced pyroclastic flows and probably formed its caldera. The ignimbrite deposit from that eruption, which had a VEI of 6, extends from the caldera to the coast, and its volume is around . Caldera lake Billy Mitchell caldera lake is about 1,013 m above sea level, has total surface area , and the maximum depth approximately 88.3 m. The only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Masaya Volcano
Masaya ( es, Volcán Masaya) is a caldera located in Masaya, Nicaragua, 20 km south of the capital Managua. It is Nicaragua's first and largest national park, and one of 78 protected areas of Nicaragua. The complex volcano is composed of a nested set of calderas and craters, the largest of which is Las Sierras shield volcano and caldera. Within this caldera lies a sub-vent, which is Masaya Volcano '' sensu stricto''. The vent is a shield type composing of basaltic lavas and tephras and includes a summit crater. This hosts Masaya caldera, formed 2,500 years ago by an 8-km³ basaltic ignimbrite eruption. Inside this caldera a new basaltic complex has grown from eruptions mainly on a semi-circular set of vents that include the Masaya and Nindiri cones. The latter host the pit craters of Masaya, Santiago, Nindiri and San Pedro. Observations in the walls of the pit craters indicate that there have been several episodes of cone and pit crater formation. Masaya continually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
