Dispersal Index
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Dispersal Index
Dispersal index is a parameter in volcanology. The dispersal index D was defined by George P. L. Walker in 1973 as the surface area covered by an ash or tephra fall, where the thickness is equal or more than 1/100 of the thickness of the fall at the vent. An eruption with a low dispersal index leaves most of its products close to the vent, forming a cone; an eruption with a high dispersal index forms thinner sheet-like deposits which extends to larger distances from the vent. A dispersal index of or more of coarse pumice is one proposed definition of a Plinian eruption. Likewise, a dispersal index of has been proposed as a cutoff for an ultraplinian eruption. The definition of 1/100 of the near-vent thickness was partially dictated by the fact that most tephra deposits are not well preserved at larger distances. Originally, the dispersal index was considered a function of the height of the eruption column. Later, a role for the size of the tephra and ash particles was identifie ...
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Parameter
A parameter (), generally, is any characteristic that can help in defining or classifying a particular system (meaning an event, project, object, situation, etc.). That is, a parameter is an element of a system that is useful, or critical, when identifying the system, or when evaluating its performance, status, condition, etc. ''Parameter'' has more specific meanings within various disciplines, including mathematics, computer programming, engineering, statistics, logic, linguistics, and electronic musical composition. In addition to its technical uses, there are also extended uses, especially in non-scientific contexts, where it is used to mean defining characteristics or boundaries, as in the phrases 'test parameters' or 'game play parameters'. Modelization When a system is modeled by equations, the values that describe the system are called ''parameters''. For example, in mechanics, the masses, the dimensions and shapes (for solid bodies), the densities and the viscosities ...
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Before Present
Before Present (BP) years, or "years before present", is a time scale used mainly in archaeology, geology and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Because the "present" time changes, standard practice is to use 1 January 1950 as the commencement date (epoch) of the age scale. The abbreviation "BP" has been interpreted retrospectively as "Before Physics", which refers to the time before nuclear weapons testing artificially altered the proportion of the carbon isotopes in the atmosphere, which scientists must now account for. In a convention that is not always observed, many sources restrict the use of BP dates to those produced with radiocarbon dating; the alternative notation RCYBP stands for the explicit "radio carbon years before present". Usage The BP scale is sometimes used for dates established by means other than radiocarbon dating, such as stratigraphy. This usage differs from t ...
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Mono Craters
Mono may refer to: Common meanings * Infectious mononucleosis, "the kissing disease" * Monaural, monophonic sound reproduction, often shortened to mono * Mono-, a numerical prefix representing anything single Music Performers * Mono (Japanese band), an instrumental band * Mono (UK band), an electronic band * Miky Mono, former member of Mono Inc., a German gothic rock band * Richard Targett and the Monos, a side-project to The Trudy Albums * ''Mono'' (Alpha Wolf album) or the title song, 2017 * ''Mono'' (Fury in the Slaughterhouse album), 1993 * ''Mono'' (The Icarus Line album), 2001 * ''Mono'' (Lena Katina album) or the title song, 2019 * ''Mono'' (The Mavericks album), 2015 * ''Mono'' (mixtape), by RM, 2018 * ''Mono'', by Paul Westerberg, packaged with ''Stereo'', 2002 Songs * "Mono" (song), by Courtney Love, 2004 * "Mono", by Fightstar from ''They Liked You Better When You Were Dead'', 2005 * "Mono", by Monrose from ''Ladylike'', 2010 * "Mono", by Whitechapel from ''O ...
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Sakurajima
Sakurajima ( ja, 桜島, literally "Cherry Blossom Island") is an active stratovolcano, formerly an island and now a peninsula, in Kagoshima Prefecture in Kyushu, Japan. The lava flows of the 1914 eruption connected it with the Ōsumi Peninsula. It is the most active volcano in Japan. As of April 2021, the volcanic activity still continues, dropping volcanic ash on the surroundings. Earlier eruptions built the white sand highlands in the region. On September 13, 2016, a team of experts from Bristol University and the Sakurajima Volcano Research Centre in Japan suggested that the volcano could have a major eruption within 30 years; since then two eruptions have occurred. Sakurajima is a stratovolcano. Its summit has three peaks, ''Kita-dake'' (northern peak), ''Naka-dake'' ( central peak) and ''Minami-dake'' (southern peak) which is active now. Kita-dake is Sakurajima's highest peak, rising to above sea level. The mountain is in a part of Kagoshima Bay known as Kinkō-wan. The ...
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Hekla
Hekla (), or Hecla, is a stratovolcano in the south of Iceland with a height of . Hekla is one of Iceland's most active volcanoes; over 20 eruptions have occurred in and around the volcano since 874. During the Middle Ages, the Icelandic Norse called the volcano the "Gateway to Hell". Hekla is part of a volcanic ridge, long. The most active part of this ridge, a fissure about long named , is considered to be within Hekla proper. Hekla looks rather like an overturned boat, with its keel being a series of craters, two of which are generally the most active. The volcano's frequent large eruptions have covered much of Iceland with tephra, and these layers can be used to date eruptions of Iceland's other volcanoes. Approximately 10% of the tephra created in Iceland in the last thousand years has come from Hekla, amounting to 5 km3. Cumulatively, the volcano has produced one of the largest volumes of lava of any in the world in the last millennium, around 8 km3. Etymolo ...
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Agua De Pau
Agua means water in Spanish. Agua may also refer to: Places * ''Agua de Dios'' (God's water), a municipality in Colombia * Volcán de Agua, a stratovolcano located in Guatemala Arts, entertainment, and media * ''Agua'' (film), a 2006 Argentine and French sports drama film * "Agua" (song), a 2020 song by Tainy and J Balvin * "Agua", a 2018 song by Saweetie from ''High Maintenance'' * "Água de Beber", a song by Antônio Carlos Jobim and Vinicius de Moraes See also * Águas Águas may refer to: Places * Dos Aguas, a municipality in the Valencian Community, Spain * Aguas, municipality in Aragon, Spain * Palace of the Marqués de Dos Aguas, a Rococo palace in Valencia, Spain People People with this surname include: * J ...
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Mount Tarawera
Mount Tarawera is a volcano on the North Island of New Zealand within the older but volcanically productive Ōkataina Caldera. Located 24 kilometres southeast of Rotorua, it consists of a series of rhyolitic lava domes that were fissured down the middle by an explosive basaltic eruption in 1886. This eruption was one of New Zealand's largest historical eruptions, and killed an estimated 120 people. The fissures run for about northeast-southwest. The volcano's component domes include Ruawahia Dome (the highest at 1,111 metres), Tarawera Dome and Wahanga Dome. It is surrounded by several lakes, most of which were created or drastically altered by the 1886 eruption. These lakes include Lakes Tarawera, Rotomahana, Rerewhakaaitu, Ōkataina, Ōkareka, Tikitapu / Blue and Rotokākahi / Green. The Tarawera River runs northeastwards across the northern flank of the mountain from Lake Tarawera. In 2000, the mountain was ceded to the Ngāti Rangitihi sub-tribe of Te Araw ...
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Rabaul
Rabaul () is a township in the East New Britain province of Papua New Guinea, on the island of New Britain. It lies about 600 kilometres to the east of the island of New Guinea. Rabaul was the provincial capital and most important settlement in the province until it was destroyed in 1994 by falling ash from a volcanic eruption in its harbour. During the eruption, ash was sent thousands of metres into the air, and the subsequent rain of ash caused 80% of the buildings in Rabaul to collapse. After the eruption the capital was moved to Kokopo, about away. Rabaul is continually threatened by volcanic activity, because it is on the edge of the Rabaul caldera, a flooded caldera of a large pyroclastic shield. Rabaul was planned and built around the harbour area known as Simpsonhafen (Simpson Harbour) during the German New Guinea administration, which controlled the region between 1884 and formally through 1919. Rabaul was selected as the capital of the German New Guinea administratio ...
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Mount Pelée
Mount Pelée or Mont Pelée ( ; french: Montagne Pelée, ; gcf, label=Antillean Creole, Montann Pèlé, meaning "bald mountain" or "peeled mountain") is an active volcano at the northern end of Martinique, an island and French overseas department in the Lesser Antilles Volcanic Arc of the Caribbean. Its volcanic cone is composed of stratified layers of hardened ash and solidified lava. Its most recent eruption was in 1932. The stratovolcano's 1902 eruption destroyed the town of Saint-Pierre, killing 29,000 to 30,000 people in the space of a few minutes, in the worst volcanic disaster of the 20th century. The main eruption, on 8 May 1902, left only two survivors in the direct path of the blast flow: Ludger Sylbaris survived because he was in a poorly ventilated, dungeon-like jail cell, and Léon Compère-Léandre, living on the edge of the city, escaped with severe burns. Geographical setting and description Mount Pelée is the result of a typical subduction zone. The subd ...
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1257 Samalas Eruption
In 1257, a catastrophic eruption occurred at the Samalas volcano on the Indonesian island of Lombok. The event had a probable Volcanic Explosivity Index of 7, making it one of the largest volcanic eruptions during the current Holocene epoch. It left behind a large caldera that contains Lake Segara Anak. Later volcanic activity created more volcanic centres in the caldera, including the Barujari cone, which remains active. The event created eruption columns reaching tens of kilometres into the atmosphere and pyroclastic flows that buried much of Lombok and crossed the sea to reach the neighbouring island of Sumbawa. The flows destroyed human habitations, including the city of Pamatan, which was the capital of a kingdom on Lombok. Ash from the eruption fell as far as away in Java; the volcano deposited more than of rocks and ash. The aerosols injected into the atmosphere reduced the solar radiation reaching the Earth's surface, causing a volcanic winter and cooling the atmospher ...
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Rinjani
Mount Rinjani ( id, Gunung Rinjani) is an active volcano in Indonesia on the island of Lombok. Administratively the mountain is in the Regency of North Lombok, West Nusa Tenggara ( Indonesian: ''Nusa Tenggara Barat'', NTB). It rises to , making it the second highest volcano in Indonesia. It is also the highest point in the Indonesian province of West Nusa Tenggara. Adjacent to the volcano is a caldera, which is filled partially by the crater lake known as Segara Anak or Anak Laut (''Child of the Sea''), due to the color of its water, as blue as the sea (''laut''). This lake is approximately above sea level and estimated to be about deep; the caldera also contains hot springs. Sasak tribe and Hindu people assume the lake and the mount are sacred and some religious activities are occasionally done in the two areas. UNESCO made Mount Rinjani Caldera a part of the Global Geoparks Network in April 2018. Geography Lombok is one of the Lesser Sunda Islands, a small archipela ...
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Kelut
The Kelud ( jv, ꦏꦼꦭꦸꦢ꧀, Kelud, sometimes spelled as ''Klut'', ''Cloot'', ''Kloet'', ''Kloete'', ''Keloed'' or ''Kelut'') is an active stratovolcano located in Kediri, East Java, Indonesia. Like many Indonesian volcanoes and others on the Pacific Ring of Fire, Kelud is known for large explosive eruptions throughout its history. More than 30 eruptions have occurred since 1000 AD. In 2007, an effusive explosion filled the crater with a lava dome. It last erupted on 13 February 2014, destroying the lava dome and ejecting boulders, stones and ashes up to West Java about from Mount Kelud. The crater filled with water during the rainy season. 1334 eruption The eruption history of Kelud is quite unique in Indonesian history, because it was one of the few volcanoes whose activities were recorded in Indonesian historical accounts. According to Nagarakretagama canto 1 stanza 4 and 5 (composed by Mpu Prapanca in 1365), King Hayam Wuruk of Majapahit was born in 1256 Saka, which c ...
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