46-520: The Kīlauea Caldera (Hawaiian: Kaluapele), officially gazetted as Kīlauea Crater , is a caldera located at the summit of Kīlauea , an active shield volcano in the Hawaiian Islands . It has an extreme length of 2.93 mi (4.72 km), an extreme width of 1.95 mi (3.14 km), a circumference of 7.85 mi (12.63 km) and an area of 4.14 sq mi (10.7 km). It contains Halemaʻumaʻu , an active pit crater near
92-409: A caldera, possibly an ash-flow caldera. The volcanic activity of Mars is concentrated in two major provinces: Tharsis and Elysium . Each province contains a series of giant shield volcanoes that are similar to what we see on Earth and likely are the result of mantle hot spots . The surfaces are dominated by lava flows, and all have one or more collapse calderas. Mars has the tallest volcano in
138-400: A diameter of 290 km (180 mi). The average caldera diameter on Mars is 48 km (30 mi), smaller than Venus. Calderas on Earth are the smallest of all planetary bodies and vary from 1.6–80 km (1–50 mi) as a maximum. The Moon has an outer shell of low-density crystalline rock that is a few hundred kilometers thick, which formed due to a rapid creation. The craters of
184-471: A magma chamber whose magma is rich in silica . Silica-rich magma has a high viscosity , and therefore does not flow easily like basalt . The magma typically also contains a large amount of dissolved gases, up to 7 wt% for the most silica-rich magmas. When the magma approaches the surface of the Earth, the drop in confining pressure causes the trapped gases to rapidly bubble out of the magma, fragmenting
230-601: A noticeable drop in temperature around the world. Large calderas may have even greater effects. The ecological effects of the eruption of a large caldera can be seen in the record of the Lake Toba eruption in Indonesia . At some points in geological time , rhyolitic calderas have appeared in distinct clusters. The remnants of such clusters may be found in places such as the Eocene Rum Complex of Scotland,
276-532: A view over the northeast part of the caldera. A stairway path descends from the pass to the caldera floor. This path is closed for safety reasons during seismic events that may precede eruptions and during eruptions. White paint marks over rocks delimit a number of footpaths ascending the lava shield inside the caldera. The lower parts of the Grand Brûlé can be visited from the N2 highway. Lava flows that have crossed
322-413: A volume of 120 million cubic metres (4.2 billion cubic feet). The caldera collapse accompanied one of the largest eruptions of lava at the volcano in the past 100 years. An eruption began on 2 July 2023 at 8:30 a.m. local time. Volcanic activity is constantly monitored by geophysical sensors ( tiltmeters , extensometers , differential GPS receivers, etc.). The data from those various sensors
368-410: Is a large cauldron -like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption . An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the structural integrity of such a chamber, greatly diminishing its capacity to support its own roof, and any substrate or rock resting above. The ground surface then collapses into
414-519: Is breached to the southeast towards the sea. The eastern flank of the volcano is unstable and is in the initial stages of failure. It will eventually collapse into the Indian Ocean and if it is a cataclysmic debris avalanche, it will generate a megatsunami . There is evidence of earlier failures on the submerged flanks and surrounding abyssal plain. The lower slopes are known as the Grand Brûlé ("Great Burn"). Most volcanic eruptions are confined to
460-405: Is ejected, the emptied chamber is unable to support the weight of the volcanic edifice above it. A roughly circular fracture , the "ring fault", develops around the edge of the chamber. Ring fractures serve as feeders for fault intrusions which are also known as ring dikes . Secondary volcanic vents may form above the ring fracture. As the magma chamber empties, the center of the volcano within
506-642: Is heated by solid flexing due to the tidal influence of Jupiter and Io's orbital resonance with neighboring large moons Europa and Ganymede , which keep its orbit slightly eccentric . Unlike any of the planets mentioned, Io is continuously volcanically active. For example, the NASA Voyager 1 and Voyager 2 spacecraft detected nine erupting volcanoes while passing Io in 1979. Io has many calderas with diameters tens of kilometers across. Piton de la Fournaise Piton de la Fournaise ( French: [pitɔ̃ də la fuʁnɛz] ; English: "Peak of
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#1732786816960552-644: Is located within Réunion National Park , a World Heritage Site . Residents of Réunion sometimes refer to Piton de la Fournaise simply as le Volcan ("the Volcano"). It is a major tourist attraction. The uppermost section of the volcano is occupied by the Enclos Fouqué , a caldera 8 kilometres (5.0 mi) wide. High cliffs, known as remparts in French, form the caldera's rim. The caldera
598-468: Is over 530,000 years old, and for most of its history, its flows have intermingled with those from Piton des Neiges , a larger, older and heavily eroded inactive volcano which forms the northwest two-thirds of Réunion Island. There were three episodes of caldera collapses 250,000, 65,000 and 5,000 years ago. The volcano was formed by the Réunion hotspot , which is believed to have been active for
644-540: Is relatively young (1.25 million years old) and unusually well preserved, and it remains one of the best studied examples of a resurgent caldera. The ash flow tuffs of the Valles caldera, such as the Bandelier Tuff , were among the first to be thoroughly characterized. About 74,000 years ago, this Indonesian volcano released about 2,800 cubic kilometres (670 cu mi) dense-rock equivalent of ejecta. This
690-974: Is sent to the Piton de la Fournaise Volcano Observatory , located in Bourg-Murat , northwest of the volcano. The observatory, founded in 1978 following the Piton-Sainte-Rose flow, is operated by the Institut de Physique du Globe de Paris (Global Geophysics Institute of Paris), in association with CNRS and the University of Réunion. The OVPF often publishes reports on Piton de la Fournaise's current activity via their website in French. RIGIC (the Réunion Island Geological Information Center) takes this information and translates it into English for distribution to
736-429: The Grand Brûlé occasionally reach the sea. Piton de la Fournaise is one of the most active volcanoes in the world, with more than 150 recorded eruptions since the 17th century. Eruptions within the caldera do not cause much devastation, because the caldera is uninhabited, but little infrastructure exists apart from the highway. Lava flows are generally confined to the caldera. However, lava flows have been known to cross
782-508: The San Juan Mountains of Colorado , where the 5,000 cubic kilometres (1,200 cu mi) Fish Canyon Tuff was blasted out in eruptions about 27.8 million years ago. The caldera produced by such eruptions is typically filled in with tuff, rhyolite , and other igneous rocks . The caldera is surrounded by an outflow sheet of ash flow tuff (also called an ash flow sheet ). If magma continues to be injected into
828-456: The most precipitation produced by a tropical cyclone in a single location . Some beaches in the proximity of the volcano are greenish in color, due to olivine sand derived from picrite basalt lavas. The Grand Brûlé is formed from solidified lava flows accumulated over hundreds of thousands of years; the most recent ones are often the darkest and most vegetation-free, while older ones can be covered by dense natural vegetation. This volcano
874-417: The Earth's volcanic activity (the other 40% is attributed to hotspot volcanism). Caldera structure is similar on all of these planetary bodies, though the size varies considerably. The average caldera diameter on Venus is 68 km (42 mi). The average caldera diameter on Io is close to 40 km (25 mi), and the mode is 6 km (3.7 mi); Tvashtar Paterae is likely the largest caldera with
920-683: The English term cauldron is also used, though in more recent work the term cauldron refers to a caldera that has been deeply eroded to expose the beds under the caldera floor. The term caldera was introduced into the geological vocabulary by the German geologist Leopold von Buch when he published his memoirs of his 1815 visit to the Canary Islands , where he first saw the Las Cañadas caldera on Tenerife , with Mount Teide dominating
966-601: The English-speaking scientific community. Procedures specify several levels of alert, which are decided by the prefect of Réunion on the basis of scientific reports: A forestry road followed by a track connects the highway of the plains in Bourg-Murat to the Pas de Bellecombe (Bellecombe Pass), where a parking lot and a snack bar are located. The Pas de Bellecombe is situated over the caldera rim cliffs and offers
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#17327868169601012-987: The Furnace" ) is a shield volcano on the eastern side of Réunion island, a French overseas department and region , in the Indian Ocean . It is currently one of the most active volcanoes in the world, along with Kīlauea in the Hawaiian Islands , Stromboli and Etna in Italy and Mount Erebus in Antarctica . A previous eruption began in August 2006 and ended in January 2007. The volcano erupted again in February 2007, on 21 September 2008, on 9 December 2010, which lasted for two days, and on 1 August 2015. The most recent eruption began on 15 September 2022. The volcano
1058-514: The Moon have been well preserved through time and were once thought to have been the result of extreme volcanic activity, but are currently believed to have been formed by meteorites, nearly all of which took place in the first few hundred million years after the Moon formed. Around 500 million years afterward, the Moon's mantle was able to be extensively melted due to the decay of radioactive elements. Massive basaltic eruptions took place generally at
1104-433: The N2 highway; areas where the road was destroyed by the eruption are signposted with the year of eruption after the road is rebuilt. In the early 2000s, the highway was destroyed one or more times a year; road engineering services then wait for the lava to cool off and build another stretch of road. For months after an eruption, the core of the lava flows can still be hot enough to steam in rainy weather. Eruptions outside of
1150-678: The San Juan Mountains of Colorado (formed during the Oligocene , Miocene , and Pliocene epochs) or the Saint Francois Mountain Range of Missouri (erupted during the Proterozoic eon). For their 1968 paper that first introduced the concept of a resurgent caldera to geology, R.L. Smith and R.A. Bailey chose the Valles caldera as their model. Although the Valles caldera is not unusually large, it
1196-726: The Solar System, Olympus Mons , which is more than three times the height of Mount Everest, with a diameter of 520 km (323 miles). The summit of the mountain has six nested calderas. Because there is no plate tectonics on Venus , heat is mainly lost by conduction through the lithosphere . This causes enormous lava flows, accounting for 80% of Venus' surface area. Many of the mountains are large shield volcanoes that range in size from 150–400 km (95–250 mi) in diameter and 2–4 km (1.2–2.5 mi) high. More than 80 of these large shield volcanoes have summit calderas averaging 60 km (37 mi) across. Io, unusually,
1242-411: The base of large impact craters. Also, eruptions may have taken place due to a magma reservoir at the base of the crust. This forms a dome, possibly the same morphology of a shield volcano where calderas universally are known to form. Although caldera-like structures are rare on the Moon, they are not completely absent. The Compton-Belkovich Volcanic Complex on the far side of the Moon is thought to be
1288-623: The building. The front entrance was later cleared out, and the church was brought back into service under the name of Notre-Dame des Laves ("Our Lady of the Lavas"). In April 2007, the volcano erupted and produced an estimated 3,000,000 cubic metres (110 million cubic feet) of lava per day. During this eruption of 2007, an incremental caldera collapse of Dolomieu occurred at the volcano over more than nine days. The collapse displaced 0.8 km × 1.1 km (0.50 mi × 0.68 mi) of floor downward by 330 m (1,080 ft), with
1334-587: The caldera atop Fernandina Island collapsed in 1968 when parts of the caldera floor dropped 350 metres (1,150 ft). Since the early 1960s, it has been known that volcanism has occurred on other planets and moons in the Solar System . Through the use of crewed and uncrewed spacecraft, volcanism has been discovered on Venus , Mars , the Moon , and Io , a satellite of Jupiter . None of these worlds have plate tectonics , which contributes approximately 60% of
1380-408: The caldera can pose serious hazards to the population, but are rare. Only six eruptions outside of the caldera have been recorded, most recently in 1986. The village of Piton-Sainte-Rose was evacuated in 1977 before it was inundated by a lava flow which destroyed several buildings. The lava flow crossed the highway and surrounded the local church, entered the front door, then stopped without destroying
1426-455: The caldera's southwestern edge. The walls of the caldera consist of fault scarps that have formed as a result of down-sinking of the caldera floor. Much of the caldera floor is covered by lava flows erupted since the 19th century. The Kīlauea Caldera and neighboring Kīlauea Iki are circled by Crater Rim Drive, an 11 mi (18 km) long paved road that provides access to Hawaiʻi Volcanoes National Park . The Hawaiian Volcano Observatory
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1472-501: The caldera. Inside the caldera is a 400 metres (1,300 ft) high lava shield named Dolomieu. At the top of this lava shield are Bory Crater ( Cratère Bory ) and Dolomieu Crater ( Cratère Dolomieu ), which is by far the wider of the two and named for French geologist Déodat Gratet de Dolomieu . Many craters and spatter cones can be found inside the caldera and on the higher flanks of the volcano. Lavas with high concentrations of iridium are routinely ejected through these vents. By
1518-676: The collapsed magma chamber, the center of the caldera may be uplifted in the form of a resurgent dome such as is seen at the Valles Caldera , Lake Toba , the San Juan volcanic field, Cerro Galán , Yellowstone , and many other calderas. Because a silicic caldera may erupt hundreds or even thousands of cubic kilometers of material in a single event, it can cause catastrophic environmental effects. Even small caldera-forming eruptions, such as Krakatoa in 1883 or Mount Pinatubo in 1991, may result in significant local destruction and
1564-403: The emptied or partially emptied magma chamber, leaving a large depression at the surface (from one to dozens of kilometers in diameter). Although sometimes described as a crater , the feature is actually a type of sinkhole , as it is formed through subsidence and collapse rather than an explosion or impact. Compared to the thousands of volcanic eruptions that occur over the course of a century,
1610-464: The formation of a caldera is a rare event, occurring only a few times within a given window of 100 years. Only eight caldera-forming collapses are known to have occurred between 1911 and 2018, with a caldera collapse at Kīlauea , Hawaii in 2018. Volcanoes that have formed a caldera are sometimes described as "caldera volcanoes". The term caldera comes from Spanish caldera , and Latin caldaria , meaning "cooking pot". In some texts
1656-467: The human species was reduced to approximately 5,000–10,000 people. There is no direct evidence, however, that either theory is correct, and there is no evidence for any other animal decline or extinction, even in environmentally sensitive species. There is evidence that human habitation continued in India after the eruption. Some volcanoes, such as the large shield volcanoes Kīlauea and Mauna Loa on
1702-429: The island of Hawaii , form calderas in a different fashion. The magma feeding these volcanoes is basalt , which is silica poor. As a result, the magma is much less viscous than the magma of a rhyolitic volcano, and the magma chamber is drained by large lava flows rather than by explosive events. The resulting calderas are also known as subsidence calderas and can form more gradually than explosive calderas. For instance,
1748-484: The landscape, and then the Caldera de Taburiente on La Palma . A collapse is triggered by the emptying of the magma chamber beneath the volcano, sometimes as the result of a large explosive volcanic eruption (see Tambora in 1815), but also during effusive eruptions on the flanks of a volcano (see Piton de la Fournaise in 2007) or in a connected fissure system (see Bárðarbunga in 2014–2015). If enough magma
1794-561: The magma to produce a mixture of volcanic ash and other tephra with the very hot gases. The mixture of ash and volcanic gases initially rises into the atmosphere as an eruption column . However, as the volume of erupted material increases, the eruption column is unable to entrain enough air to remain buoyant, and the eruption column collapses into a tephra fountain that falls back to the surface to form pyroclastic flows . Eruptions of this type can spread ash over vast areas, so that ash flow tuffs emplaced by silicic caldera eruptions are
1840-476: The only volcanic product with volumes rivaling those of flood basalts . For example, when Yellowstone Caldera last erupted some 650,000 years ago, it released about 1,000 km of material (as measured in dense rock equivalent (DRE)), covering a substantial part of North America in up to two metres of debris. Eruptions forming even larger calderas are known, such as the La Garita Caldera in
1886-557: The past 66 million years. There is evidence for explosive eruptions in the past. One explosive eruption about 4,700 years ago may have had a VEI (Volcanic Explosivity Index) of 5, which is the same as the 18 May 1980 eruption of Mount St. Helens . Most eruptions of Piton de la Fournaise are of the Hawaiian style : fluid basaltic lava flowing out with fire fountaining at the vent. Occasionally, phreatic eruptions (groundwater steam-generated eruptions) occur. Lava flows crossing
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1932-462: The ring fracture begins to collapse. The collapse may occur as the result of a single cataclysmic eruption, or it may occur in stages as the result of a series of eruptions. The total area that collapses may be hundreds of square kilometers. Some calderas are known to host rich ore deposits . Metal-rich fluids can circulate through the caldera, forming hydrothermal ore deposits of metals such as lead, silver, gold, mercury, lithium, and uranium. One of
1978-429: The trailhead of the summit path there lies a small noteworthy crater called Formica Leo , named for its resemblance to the sand pit trap of an antlion . Located outside of the main caldera is Commerson Crater , an inactive caldera notable for receiving intense rainfall, particularly during tropical storms. During Cyclone Hyacinthe in January 1980, it received 6,433 millimetres (253.3 in) of rainfall in 15 days,
2024-653: The world's best-preserved mineralized calderas is the Sturgeon Lake Caldera in northwestern Ontario , Canada, which formed during the Neoarchean era about 2.7 billion years ago. In the San Juan volcanic field , ore veins were emplaced in fractures associated with several calderas, with the greatest mineralization taking place near the youngest and most silicic intrusions associated with each caldera. Explosive caldera eruptions are produced by
2070-474: Was established on the rim of the Kīlauea Caldera in 1912. Outside of Halemaʻumaʻu, eruptions from the Kīlauea Caldera have taken place in 1982, 1975, 1974, 1971, 1921, 1919, 1918, and possibly in 1820 and 1790 . This Hawaiʻi state location article is a stub . You can help Misplaced Pages by expanding it . Caldera A caldera ( / k ɔː l ˈ d ɛr ə , k æ l -/ kawl- DERR -ə, kal- )
2116-464: Was the largest known eruption during the ongoing Quaternary period (the last 2.6 million years) and the largest known explosive eruption during the last 25 million years. In the late 1990s, anthropologist Stanley Ambrose proposed that a volcanic winter induced by this eruption reduced the human population to about 2,000–20,000 individuals, resulting in a population bottleneck . More recently, Lynn Jorde and Henry Harpending proposed that
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