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49-641: The area of the caldera consists of 24 craters and volcanic edifices. Most of them lie under the Gulf of Naples . There are effusive gaseous manifestations in the Solfatara crater, which was believed in ancient Rome to be the home of Vulcan , the god of fire. The area features bradyseismic phenomena, which are most evident at the Macellum of Pozzuoli , misidentified as a temple of Serapis : bands of boreholes left by marine molluscs on marble columns show that

98-575: A " super volcano " that might kill millions. A study from the Istituto Nazionale di Geofisica e Vulcanologia reported that the volcanic unrest of the Campi Flegrei caldera from January 2012 to June 2013 was characterised by rapid ground uplift of about 11 cm (4 in), with a peak rate of about 3 cm (1 in) per month during December 2012. It added that from 1985 to 2011 the dynamics of ground uplift were mostly linked to

147-409: 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

196-400: 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

245-471: 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

294-441: A maximum average of 0.7 cm per month since July 2017. Gas emissions and fumarole temperatures did not change significantly. In May 2024 the ground was reported to be rising by 2 cm per month, with the rate increasing. On April 26, 2020, a moderate earthquake swarm hit Campi Flegrei caldera, with about 34 earthquakes ranging between magnitude 0 and magnitude 3.1 centred around the port city of Pozzuoli. The strongest quake in

343-560: A new study by University College London and the Vesuvius Observatory published in Nature Communications concluded that an eruption might be closer than previously thought. The study found that the geographical unrest since the 1950s has a cumulative effect, causing a build-up of energy in the crust and making the volcano more susceptible to eruption. On 21 August 2017 there was a magnitude 4 earthquake on

392-601: 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,

441-513: A swarm of 150 earthquakes in a few hours, one of magnitude 4.4 causing fear among the population of Pozzuoli and some cracks and minor damage to buildings. Schools and a prison were evacuated. In respect of its 18th and 19th century role in the development of geoscience, not least volcanology, this locality was included by the International Union of Geological Sciences (IUGS) in its assemblage of 100 'geological heritage sites' around

490-523: Is a peer-reviewed , open access , scientific journal published by Nature Portfolio since 2010. It is a multidisciplinary journal that covers the natural sciences , including physics , chemistry , earth sciences , medicine , and biology . The journal has editorial offices in London, Berlin, New York City, and Shanghai. The founding editor-in-chief was Lesley Anson, followed by Joerg Heber , Magdalena Skipper , and Elisa De Ranieri . As of 2022,

539-410: 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

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588-405: 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

637-580: 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. Nature Communications Nature Communications

686-485: Is rare trachybasalt . Three geological phases or periods are recognised and distinguished. Volcanic deposits indicative of eruption have been dated by argon at  315,000, 205,000, 157,000 and 18,000  years ago. In 1538, an eight-day eruption in the area deposited enough material to create a new hill, Monte Nuovo . It has risen about 2 m (7 ft) from ground level since 1970. The volcanic island of Ischia suffered three destructive earthquakes in 1828, 1881, and

735-540: 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

784-508: 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

833-417: 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

882-683: 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

931-514: 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

980-678: 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

1029-726: 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,

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1078-411: 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

1127-587: 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

1176-400: The caldera's hydrothermal system, and that this relation broke down in 2012. The driving mechanism of the ground uplift changed to periodical emplacement of magma within a flat sill -shaped magmatic reservoir about 3,000 m (9,843 ft) in depth, 500 m (1,640 ft) south from the port of Pozzuoli. In December 2016, activity became so high that an eruption was feared. In May 2017

1225-676: 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

1274-416: The earth's surface near Pompeii, in order to monitor the massive molten rock chamber below and provide early warning of any eruption. Local scientists were worried that drilling could precipitate an eruption or earthquake; programme scientists said it was no different from industrial drilling in the area. The drilling was halted in 2010, but later resumed. A Reuters article emphasized that the area could produce

1323-501: The editors are Nathalie Le Bot for health and clinical sciences, Stephane Larochelle for biological sciences, Enda Bergin for chemistry and biotechnology, and Prabhjot Saini for physics and earth sciences. Starting October 2014, the journal only accepted submissions from authors willing to pay an article processing charge . Until the end of 2015, part of the published submissions were only available to subscribers. In January 2016, all content became freely accessible. Starting from 2017,

1372-403: 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,

1421-503: The following years several additional Communications journals were established: Communications Materials in 2020, Communications Earth & Environment in 2020, Communications Medicine in 2021, , Communications Engineering in 2022 and Communications Psychology in 2022. These open-access journals offer a lower publication fee than Nature Communications , reflecting their more specialist remits. Manuscripts rejected by Nature Publishing Group journals can choose to transfer

1470-464: 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

1519-565: The hot fluids model, steam and hot gases generated deeper underground are the cause. In this case activity could stop abruptly, or lead to a phreatic eruption of hot liquids, gases and rock fragments, rather than lava. While very dangerous, it is less so than a magma eruption. An answer to this question would help to estimate how likely this volcano, and other large volcanoes and supervolcanoes , are to erupt, and what warning signs to look out for. A February 2020 status report indicated that earth uplift around Pozzuoli continued at steady rates, with

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1568-467: 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

1617-429: 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,

1666-607: The journal offers a deposition service to authors for preprints of articles "under consideration" as part of the submission process. The journal is abstracted and indexed in: According to the Journal Citation Reports , the journal has a 2023 impact factor of 14.7. In 2017, the creation of three "subjournals" under the Communications brand was announced: Communications Biology , Communications Chemistry , and Communications Physics . In

1715-484: 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

1764-592: The level of the site in relation to sea level has varied. Hydrothermal activity can still be observed at Lucrino , Agnano and the town of Pozzuoli . At present, the Phlegraean Fields area comprises the Naples districts of Agnano and Fuorigrotta , the area of Pozzuoli, Bacoli , Monte di Procida , Quarto , the Phlegraean Islands , Ischia , Procida and Vivara . The Solfatara crater

1813-561: 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

1862-638: The most destructive one in 1883 , with a magnitude of 4.2–5.2 and causing catastrophic shaking assigned XI ( Extreme ) on the MCS scale . Extreme damage was reported on the island, and over 2,000 residents perished. A 2009 journal article stated that deformation of the caldera centre near Pozzuoli might presage an eruptive event within decades. In 2012 the International Continental Scientific Drilling Program planned to drill 3.5 kilometres (11,000 feet) below

1911-476: 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

1960-564: The preparation of contingency plans to evacuate up to 360,000 people in the area. Despite a further 4.0 quake on 2 October, most volcanologists consider that a major eruption is not expected imminently. The best-case scenario was deemed to be the activity ending, as happened after much activity on the 1980s. The worst would be an eruption like the one of 1538. A study by Italy's National Institute of Geophysics and Volcanology (INGV) and University College London (UCL) in June 2023 concluded that

2009-462: 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

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2058-474: The sequence was of magnitude 3.1, the strongest at the time since the last major period of unrest and rapid uplift in 1982-1984. However, no new fumaroles were reported. Volcanic activity was reported in January 2022 to be increasing. In the year to September 2023 seismic activity had intensified, particularly in the later months. On 27 September 2023, a magnitude 4.2 earthquake—the strongest in 40 years—prompted

2107-611: The variety used comprises at least 90% of the blend and the wine is fermented to at least 12% alcohol for reds and 11% for whites. Red Campi Flegrei is a blend of 50–70% Piedirosso , 10–30% Aglianico and/or Sciascinoso and up to 10% of other local (both red and white) grape varieties. The whites are composed of 50–70% Falanghina , 10–30% Biancolella and/or Coda di Volpe , with up to 30% of other local white grape varieties. Campi Flegrei has had strategic and cultural importance. Caldera A caldera ( / k ɔː l ˈ d ɛr ə , k æ l -/ kawl- DERR -ə, kal- )

2156-514: The volcano was edging towards "breaking point" and in an "extremely dangerous state". Nello Musumeci , Italian minister for civil protection, was to ask Neapolitan local officials for an "acceleration in the drafting of exodus plans in the event of an emergency"; he said that evacuation would only be carried out in the event of "extreme necessity". Mass evacuation plans were to be tested at the end of May 2024. Intense seismic activity continues in 2024. On 20 May 2024, seismic activity intensified, with

2205-545: The western edge of the Campi Flegrei area. Two people were killed and many more people injured in Casamicciola on the northern coast of the island of Ischia, which is south of the epicentre. The reason for the seismicity and bulging ground is not known as of 2023. According to one model, called in a Scientific American article the shallow magma model, magma is pushing to break through the surface, making an explosive eruption with magma flow likely. In what has been termed

2254-663: The world in a listing published in October 2022. Italian wine , both red and white, under the Campi Flegrei DOC appellation comes from this area. Grapes destined for DOC production must be harvested up to a maximum yield of 12 tonnes / hectare for red grape varieties , and 13 t/ha for white grape varieties. The finished wines need to be fermented to a minimum alcohol level of 11.5% for reds and 10.5% for whites. While most Campi Flegrei wines are blends, varietal wines can be made from individual varieties, provided

2303-653: 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

2352-517: Was accessible on foot until 2017 and contains many steam-emitting fumaroles and over 150 pools, at the last count, of boiling mud. Several subsidiary cones and tuff craters, one filled by Lake Avernus , lie within the caldera. The magma underlying the Phlegraean Fields produces lavas of varying composition but generally rich in potassium . Trachyte is the most common eruptive product, unusually alkali-rich in some cases. Peralkaline phonolitic trachyte and latite have also been produced, and there

2401-464: 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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