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Active Volcanoes
An active volcano is a volcano that is currently erupting, or has the potential to erupt in the future. Conventionally it is applied to any that have erupted during the Holocene (the current geologic epoch that began approximately 11,700 years ago). A volcano that is not currently erupting but could erupt in the future is known as a dormant volcano. Volcanoes that will not erupt again are known as extinct volcanoes. Overview There are 1,350 potentially active volcanoes around the world, 500 of which have erupted in historical time. Many active volcanoes are located along the Pacific Rim, also known as the Pacific Ring of Fire. An estimated 500 million people live near active volcanoes. ''Historical time'' (or recorded history) is another timeframe for ''active''. The span of recorded history differs from region to region. In China and the Mediterranean, it reaches back nearly 3,000 years, but in the Pacific Northwest of the United States and Canada, it reaches back less tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Map Plate Tectonics World
A map is a symbolic depiction of interrelationships, commonly spatial, between things within a space. A map may be annotated with text and graphics. Like any graphic, a map may be fixed to paper or other durable media, or may be displayed on a transitory medium such as a computer screen. Some maps change interactively. Although maps are commonly used to depict geography, geographic elements, they may represent any space, real or fictional. The subject being mapped may be two-dimensional such as Earth's surface, three-dimensional such as Earth's interior, or from an abstract space of any dimension. Maps of geographic territory have a very long tradition and have existed from ancient times. The word "map" comes from the , wherein ''mappa'' meant 'napkin' or 'cloth' and ''mundi'' 'of the world'. Thus, "map" became a shortened term referring to a flat representation of Earth's surface. History Maps have been one of the most important human inventions for millennia, allowin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Etna
Mount Etna, or simply Etna ( or ; , or ; ; or ), is an active stratovolcano on the east coast of Sicily, Italy, in the Metropolitan City of Catania, between the cities of Messina, Italy, Messina and Catania. It is located above the Convergent boundary, convergent plate margin between the African Plate and the Eurasian Plate. It is one of the tallest active volcanoes in Europe, and the tallest peak in Italy south of the Alps with a current height (September 2024) of , though this varies with summit eruptions. For instance, in 2021 the southeastern crater reached a height of , but was then surpassed by the Voragine crater after the summer 2024 eruptions. Etna covers an area of with a basal circumference of . This makes it by far the largest of the three volcanism in Italy, active volcanoes in Italy, being about two and a half times the height of the next largest, Mount Vesuvius. Only Teide, Mount Teide on Tenerife in the Canary Islands surpasses it in the whole of the Euro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erta Ale
Erta Ale (or Ertale or Irta'ale; Amharic: ኤርታሌ) is a continuously active basaltic shield volcano in the Afar Region of northeastern Ethiopia, which is itself part of the wider Afar Triangle (a barren desert region straddling Djibouti, Ethiopia and Eritrea). The volcano is located in the Danakil Depression, an area on the border between Ethiopia and Eritrea that is below sea level. It is the most active of the volcanoes in Ethiopia. Geology Erta Ale is high, with one or sometimes two active lava lakes at the summit which occasionally overflow on the south side of the volcano. It is notable for holding the longest-existing lava lake, present since at least 1906.Barnie, T.D., Oppenheimer, C., and Pagli, C. (2016). Magmatic Rifting and Active Volcanism. Geological Society, London, Special Publications, 420, 181–208. https://doi.org/10.1144/SP420.15 Volcanoes with lava lakes are rare: there were only eight in the world reported in 2019. ''Erta Ale'' means "smoking mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava Lake Nyiragongo 2
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from . The volcanic rock resulting from subsequent cooling is often also called ''lava''. A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments called tephra, not lava flows.) The viscosity of most lava is about that of ketchup, roughly 10,000 to 100,000 times that of water. Even so, lava can flow great distances before cooling causes it to solidify, because lava exposed to air quickly develops a solid crust that insulates the remaining liquid lava, helping to keep it hot and inviscid enough to continue flowing. Etymology The word ''lava'' comes from Italian and is probably derived from the Latin word ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surface area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With nearly billion people as of , it accounts for about of the world's human population. Demographics of Africa, Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will exceed 3.8 billion people by 2100. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania. Scholars have attributed this to different factors including Geography of Africa, geography, Climate of Africa, climate, corruption, Scramble for Africa, colonialism, the Cold War, and neocolonialism. Despite this lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nyamuragira
Nyamuragira, also known as Nyamulagira, is an active shield volcano in the Virunga Mountains of the Democratic Republic of the Congo, situated about north of Lake Kivu. The name is derived from Bantu languages in the region, ''Kuragira nyamu'', meaning to '' herd animals''; ''nyamu'' means ''animal'' or ''cows''. It has been described as Africa's most active volcano and has erupted over 40 times since 1885. As well as eruptions from the summit, there have been numerous eruptions from the flanks of the volcano, creating new smaller volcanoes that have lasted only for a short time (e.g. Murara from late 1976 to 1977). Recent eruptions occurred on 2 January 2010, 8 November 2011 and 23 May 2021. Geography and geology Nyamuragira volcano is an active volcano near the city of Goma in the Democratic Republic of the Congo, situated about north of Lake Kivu. It is in the Nord-Kivu Province. It is north-north-west of Nyiragongo, the volcano which caused extensive damage to the ci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Nyiragongo
Mount Nyiragongo ( ) is an active stratovolcano with an elevation of in the Virunga Mountains associated with the Albertine Rift. It is located inside Virunga National Park, in the Democratic Republic of the Congo, about north of the town of Goma and Lake Kivu and just west of the border with Rwanda. The main crater is about wide and usually contains a lava lake. The crater presently has two distinct cooled lava benches within the crater walls – one at about and a lower one at about . Nyiragongo's lava lake has at times been the most voluminous known lava lake in recent history. The depth of the lava lake varies considerably. A maximum elevation of the lava lake was recorded at about prior to the January 1977 eruption – a lake depth of about . Following the January 2002 eruption, the lava lake was recorded at a low of about , or below the rim. The level has gradually risen since then. Nyiragongo and nearby Nyamuragira are together responsible for 40% of Africa's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mauna Loa
Mauna Loa (, ; ) is one of five volcanoes that form the Island of Hawaii in the U.S. state of Hawaii in the Pacific Ocean. Mauna Loa is Earth's largest active volcano by both mass and volume. It was historically considered to be the largest volcano on Earth until the submarine mountain Tamu Massif was discovered to be larger. Mauna Loa is a shield volcano with relatively gentle slopes, and a volume estimated at , although its peak is about lower than that of its neighbor, Mauna Kea. Lava eruptions from Mauna Loa are silica-poor and very fluid, and tend to be non-explosive. Mauna Loa has likely been erupting for at least 700,000 years, and may have emerged above sea level about 400,000 years ago. Some dated rocks are 470,000 years old. The volcano's magma comes from the Hawaii hotspot, which has been responsible for the creation of the Hawaiian Island chain over tens of millions of years. The slow drift of the Pacific Plate will eventually carry Mauna Lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sangay
Sangay (also known as Macas, Sanagay, or Sangai) is an Volcano#Active, active stratovolcano in central Ecuador. It exhibits mostly Strombolian eruption, strombolian activity. Geologically, Sangay marks the southern boundary of the Northern Volcanic Zone, and its position straddling two major pieces of Crust (geology), crust accounts for its high level of activity. Sangay's approximately 500,000-year-old history is one of instability; two previous versions of the mountain were destroyed in massive flank collapses, evidence of which still litters its surroundings today. Due to its remoteness, Sangay hosts a significant biological community with fauna such as the mountain tapir, giant otter, Andean cock-of-the-rock and king vulture. Since 1979, its ecological community has been protected as part of the Sangay National Park. Although mountain climbing, climbing the mountain is hampered by its remoteness, poor weather conditions, river flooding, and the danger of falling ejecta, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa María (volcano)
Santa María Volcano is a large active volcano in the western highlands of Guatemala, in the Quetzaltenango Department near the city of Quetzaltenango. It is part of the mountain range of the Sierra Madre. The volcano was known as Gagxanul in the local Kʼicheʼ language, which means "Naked Volcano or Mountain", before the 16th century Spanish conquest of the region. The VEI-6 eruption of Santa María Volcano in 1902 was one of the three largest eruptions of the 20th century, after the 1912 Novarupta and 1991 Mount Pinatubo eruptions. It is also one of the five biggest eruptions of the past 200 (and most likely 300) years. Geological history Santa María Volcano is part of the Sierra Madre range of volcanoes, which extends along the western edge of Guatemala, separated from the Pacific Ocean by a broad plain. The volcanoes are formed by the subduction of the Cocos Plate under the Caribbean Plate, which led to the formation of the Central America Volcanic Arc. Eruption ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Yasur
Mount Yasur is a volcano on Tanna Island, Vanuatu, high above sea level, on the coast near Sulphur Bay, northeast of the taller Mount Tukosmera, which was active in the Pleistocene. It has a largely unvegetated pyroclastic cone with a nearly circular summit crater 400 m in diameter. It is a stratovolcano, caused by the eastward-moving Indo-Australian Plate being subducted under the westward-moving Pacific Plate. It has been erupting nearly continuously for several hundred years, although it can usually be approached safely. Its eruptions, which often occur several times an hour, are classified as Strombolian or Vulcanian. A large lava plain creeps across the valley at the base. The glow of the volcano was apparently what attracted Captain James Cook on the first European journey to the island in 1774. Today, the mountain is a sacred area for the John Frum cargo cult. Members of the cult revere John Frum, a deified messenger who foretold the bringing of wealth to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Réunion
Réunion (; ; ; known as before 1848) is an island in the Indian Ocean that is an overseas departments and regions of France, overseas department and region of France. Part of the Mascarene Islands, it is located approximately east of the island of Madagascar and southwest of the island of Mauritius. , it had a population of 896,175. Its capital and largest city is Saint-Denis, La Réunion, Saint-Denis. Réunion was uninhabited until French immigrants and colonial subjects settled the island in the 17th century. Its tropical climate led to the development of a plantation economy focused primarily on sugar; slaves from East Africa were imported as fieldworkers, followed by Malays, Annamite, Vietnamese, Chinese, and Indians as indentured laborers. Today, the greatest proportion of the population is of mixed descent, while the predominant language is Réunion Creole, though French remains the sole official language. Since 1946, Réunion has been governed as a regions of France, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
