The Last Day of Pompeii
Кальдера Кампи Флегреи: Вулканическая история
Кампи Флегреи, находящиеся к западу от Неаполя, произвели самое крупное вулканическое извержение, произошедшее в Европе за последние 200 000 лет. Верхняя половина кальдеры, диаметром около 13 километров (8 миль), находится на суше, с городом Поццуоли посреди, тогда как нижняя половина находится под водой в Бухте Неаполя и Тирренском море. Кальдера образовалась во время огромного извержения Кампанской Игнибритовой пылевой волны 40 000 лет назад с объемом 181–265 км3 (43–64 мили) с классификацией 7 по индексу вулканической взрывоопасности. Это извержение покрыло большую часть южной Италии и восточного Средиземноморья толстым слоем вулканической пеплом. Крупное извержение, произошедшее 15 000 лет назад, привело к образованию неаполитанского желтого туфа, покрывающего площадь более 1 000 км2 (386 миль2) с оцениваемым объемом около 40 км3 (примерно 10 миль3) извергнутой магмы.
Хотя это впечатляет, объемы магмы значительно меньше объема магмы, извергнутой во время формирования кальдеры Йеллоустоун, который составил около 1000 км3 (240 миль3).
Записи деформации Кампи Флегреи
Записи деформации в Кампи Флегреи восходят к римским временам. Мраморные колонны в 2000-летнем рынке Поццуоли обеспечивают замечательную запись долгосрочных узоров подъема и опускания. Нижние трети колонн искурочены от бурения морскими моллюсками, что означает, что рынок был построен, когда земля находилась выше уровня моря, погрузилась примерно на 7 метров (23 фута) и была затоплена морской водой, а затем снова возросла из воды — все это примерно за последние 2 000 лет!
Серапеум, Римский рынок в Поццуоли, Италия
Серапеум, римский рынок в Поццуоли, Италия, записывает деформацию кальдеры Кампи Флегреи за два тысячелетия. Он был построен над уровнем моря примерно 2000 лет назад, но сквозные отверстия от моллюсков на больших мраморных колоннах показывают, что он опускался на 7 метров (23 фута) ниже уровня моря, прежде чем был поднят снова выше уровня моря в течение последних нескольких сотен лет.
Национальный парк Италии и туристический объект
Национальный парк Везувий и его сеть троп
Незаконные застройки в Италии: Риски Вулкана Везувия
В Италии, по оценкам, около 6 миллионов человек живут в незаконно построенных домах, следствие лет государственного управления, от полного неграмотности до явного коррупционизма. Бурное урбанизирование Италии в середине 20-го века привело к тому, что застройщики спешили строить дома, отвечающие спросу общественности, но часто нарушали строительные нормы. Типичный ответ правительства заключался в неявной поддержке, а иногда даже прямом участии, в обходе собственных регуляций.
Это необузданное урбанизирование превратило Везувий в один из самых опасных вулканов мира. Лучия Паппалардо, вулканолог, старший исследователь в Обсерватории Везувия и родом из Неаполя, подчеркивает, что катастрофическое извержение непредсказуемо, и единственный способ обеспечить безопасность населения – это предварительная эвакуация, сложная задача в связи с плотностью населения и недостаточными путями эвакуации.
Итальянское правительство многие годы игнорировало эти очевидные риски. Пока в 1980-х годах государство не начало ограничивать городское строительство вокруг Везувия, выделив определенные зоны как красные. Однако эти ограничения были полны дыр, что позволило продолжать строительство в этих зонах в обмен на амнистические выплаты, ставя людей перед огромным риском жить на грани до следующего извержения.
Источники
24 августа 79 года н. э., после веков спячки, вулкан Везувий извергся, потрясая южную Италию и всю Римскую империю. Извержение было настолько катастрофичным, что уничтожило процветающие римские города Помпеи и Геркуланум, погубив тысячи человек. Города, засыпанные толстым слоем пепла, пемзы и грязи, так и не были восстановлены и постепенно исчезли из истории. Затем, в 18 веке, Помпеи и Геркуланум были вновь обнаружены и раскопаны, вызвав интерес к древней истории Рима и археологии. Более того, эти города, зарытые на столетия, предоставляют нам беспрецедентную археологическую документацию повседневной жизни древнего Рима, застывшую во времени. А также ценные научные данные, которые могут помочь предотвратить дальнейшие катастрофы.
Извержение вулкана Везувия – непреодолимая катастрофа
Уничтожение храма Ирода в Иерусалиме Титом.
For centuries, the ancient Roman cities of Pompeii and Herculaneum thrived near the base of Mount Vesuvius at the Bay of Naples. In the early years of the Roman Empire, around 20,000 people lived in Pompeii, a vibrant trade hub in southern Italy. The area was known for its rich soil, ideal for numerous vineyards and orchards. Herculaneum was a resort town of 5,000, a favorite summer destination for wealthy senators and . However, at noon, on the 24th of August, 79 CE, this prosperity and pleasure came to an end when the peak of nearby Mount Vesuvius exploded.
For the next 12 hours, volcanic ash and pumice showered Pompeii and Herculaneum, forcing the people to flee in terror. Those who remained met their tragic and sudden end when a lethal cloud of hot ash and gas engulfed the area, burning or asphyxiating the unfortunate people. Then, a flood of volcanic mud and rock buried Pompeii and Herculaneum.
However, It Also Preserved Pompeii and Herculaneum
Plaster casts of some of the victims of the eruption of Mount Vesuvius in 79 CE, via Antiquarium Museum of Pompeii
Although the eruption killed thousands and erased Pompeii and Herculaneum from the map of the Roman Empire, it had an unexpected side effect. Namely, the layers of ash and pumice formed a natural “time capsule” that preserved the buildings, , sculptures, and even human remains until their rediscovery almost 1700 years later. As a result, the preserved ruins of Pompeii and Herculaneum offer us a unique and valuable glimpse into ancient Roman society
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The buildings, artwork and everyday objects found in the two cities reveal the culture, customs and beliefs of the former citizens. In addition, the preserved human remains give us information on the physical characteristics, , and health of the people and the circumstances of their tragic death. Thus, Pompeii and Herculaneum are probably the most important places to study Roman history.
Vesuvius’ Eruption Was Recorded by an Eyewitness
Pliny the Younger and his Mother at Misenum AD 79, by Angelica Kauffmann, 1785, via Princeton University Art Museum
Mount Vesuvius erupted in the “golden era” of Roman history. At the moment of the disaster, the Roman Empire was at its apex, enjoying a long and unprecedented period of peace and prosperity – the . Thus, the eruption’s impact was not so damaging to the Empire. Yet, it would be wrong to think that the Romans were not affected by the disaster. In fact, we have a rare and incredibly detailed report of the disaster, written by one of the eyewitnesses – Pliny the Younger.
Thanks to Pliny’s letters, we know of the events that occurred in the first hours of the eruption. Also, we know that his uncle, celebrated naturalist Pliny the Elder, the commander of the Roman fleet at Misenum at the time of the Vesuvius’ eruption, organized a doomed rescue expedition. Unfortunately, soon after reaching the port of Stabiae, on the other side of the Bay of Naples, Pliny the Elder succumbed to toxic gas and died. This seems to be the only attempted rescue of the unfortunate people. Emperor Titus was later criticized for his inadequate response.
The Scientific Importance of Mount Vesuvius’ Eruption
A photograph of a Plinian eruption of Mount St. Helens, 1980, via United States National Park Service
The eruption of Mount Vesuvius was a major disaster for the ancient Romans. However, the ancient catastrophe transcends the place and time. The detailed eyewitness account of Pliny the Younger allowed historians and scientists to reconstruct the timeline of the eruption. More importantly, the account of the eruption left a significant contribution to the field of volcanology. The particular type of volcanic eruption that doomed Pompeii and Herculaneum is nowadays recognized as “Plinian.” Together with other well-recorded Plinian eruptions, such as that of Krakatoa in 1883 or Mount St. Helens in 1980, the Vesuvius eruption provided scientists and researchers, providing us with a better understanding of the Earth’s natural processes and how humans can prepare for and mitigate the effects of natural disasters.
Impact of the Mount Vesuvius Eruption on Culture and Art
Vesuvius in Eruption, by J. M. W. Turner, circa 1817-1820, via Yale Center for British Art
In addition, the ruins of Pompeii and Herculaneum renewed interest in , and many buildings in Europe and America were constructed in the neoclassical style. It also inspired the design of public parks and gardens, with many features, such as fountains and sculptures modelled on ancient Roman examples.
The excavated villa of San Marco at Stabiae, via Antiquarium Museum of Pompeii
Lastly, the disaster significantly impacted the field of archaeology, as the rediscovery of Pompeii and Herculaneum led to a renewed interest in the study of the ancient world, and the excavation of the cities became a major focus of archaeological research. The discoveries made at Pompeii and Herculaneum provided essential insight into the daily lives, customs, and beliefs of ancient Romans and helped to shape our understanding of their world.
In 79 C.E., an ash column with a mushroom top towered over the ancient Roman city of Pompeii as residents scrambled to flee the eruption of Mount Vesuvius.
The effects of the eruption were devastating to the area. As one ancient historian, Pliny the Younger, recounted the events to another historian, Cornelius Tacitus, “On Mount Vesuvius sheets of fire and leaping flames blazed at several points, their bright glare emphasized by the darkness of night.”
Modern research suggests the eruption only took 15 minutes to wreak havoc on the city, killing an estimated 2,000 people, per The Guardian. In the aftermath of the catastrophic eruption, it’s believed more people died as they inhaled rain of lapilli.
The pumice, volcanic debris and ash that fell in a deluge upon the city covered the remaining bodies, buildings, horses, loaves of bread — everything in the city. The city was buried and preserved. It’s a paradox of sorts. The volcano which led to the death of thousands of residents and destroyed the daily lives of survivors also led to the preservation of the city.
Over the course of the last few hundred years, archaeologists have worked to uncover what remains. But a large swath of the city remains unexplored: around a quarter of the city has yet to be excavated, National Geographic reported.
What does the future look like for this ancient city?
Archaeologists are working out what to excavate next. And at the same time, Pompeii is experiencing a boom in tourism. It was a good summer for the city. The number of tourists who visited Pompeii in a single day was record-breaking, per CNN.
The city is different than some other archaeological sites because there are several buildings preserved, not just one. As visitors observe what remains of luxurious private villas, they can creatively imagine what it would have been like to live there in its heyday.
Take the House of the Faun, for example. It’s not so much a house as it is a sprawling palace with colorful mosaics tiled on the floor and homages to ancient Roman gods scattered across the land. The home is full of high ceilings, animal artwork and household objects, providing a clear reminder that once upon a time, someone lived here.
https://youtube.com/watch?v=-X4i0psJ2p0%3Ffeature%3Doembed
While at Pompeii, you can stroll over to the Villa of Mysteries, which is home to a brightly colored fresco that is stretched across three walls. The fresco features Dionysus (the god of grapes, wine, theater and festivity) alongside his wife Ariadne, fauns and maenads, all engaging in ritualistic activities associated with the worship of Dionysus.
The rites and rituals depicted on the fresco are not entirely understood by scholars. They are part of the mysterious rituals surrounding Dionysus that have remained mysterious through the present day.
https://youtube.com/watch?v=SEzDiejb1a0%3Ffeature%3Doembed
These magnificent villas reveal clues about what daily life was like for a portion of ancient Romans. Keep in mind, the residents of these two villas would have had something of a fortune. But other archaeological advancements tell us what daily life would have looked like for most people living in the area.
Between what historians said about daily life and archaeological discoveries, scholars have been able to piece together what it would have been like to live in Pompeii.
Without the buzz of an alarm clock, people relied on the sun rising and setting for their sleeping schedules. There were a number of occupations in ancient Pompeii and Rome, like barbers, farmers, snack shop owners, seamstresses, shop owners and numerous political jobs.
One of the more surprising findings has to with bread.
When historians analyzed the nutrition of people who lived in the area, they didn’t find disparities in nutrition between poorer people and wealthier people.
“Reasons for this have been appointed to the 30 bakeries found in Pompeii, and the 81 carbonised loaves, cooked and ready to be sold, left perfectly preserved in one of the town’s many ovens,” according to tour company Sightseeing Tours Italy’s website. “This suggests that rich and poor alike would have fed on the same bread, explaining their similarities in nutrition.”
Historians analyzed the preserved trash and also discovered that the diets across different economic classes were more similar than what was previously expected. “Evidence of fish bones, chicken, fruit and nuts were found, demonstrating that even normal everyday people ate well,” per the website.
While a fair amount about the city is known, there is still more excavating that archaeologists plan on doing.
“Excavating at Pompeii is a huge responsibility. Excavation is an unrepeatable event,” Gabriel Zuchtriegel, site director of the Pompeii archaeological park, said. “What is excavated remains so forever. It is therefore necessary to devote great care to documenting and analysing each find together with all the stratigraphic relationships and to working out, right from the start, how to safeguard and restore what we find.”
Some of the recent discoveries from excavations have hit the headlines, like the proto-pizza fresco. In the ancient city of Pompeii, archaeologists found a fresco near a bakery depicting a flatbread, similar to a pizza. While the flatbread doesn’t have the “classic ingredients” pizza has, archaeologists at the Unesco World Heritage park told BBC the flatbread “may have been eaten with fruits such as pomegranates or dates, or dressed with spices and a type of pesto sauce.”
Archaeologists also found a kitchen shrine that is decorated with a bunch of serpents, along with a new bakery, according to BBC.
Other discoveries have included decorative bowls, a table, a closet for dishware, a trunk, objects inside bedrooms and kitchens, the remains of a bed frame, an incense burner and a fragment of a plate, The Guardian reported. While these may all seem like small findings, they shed light on what daily life was like for the residents of Pompeii.
Archaeologists have been trying to “solve the problems of water seepage between the excavated area and the unexplored area of the ancient city,” per the Pompeii Sites website, as they accommodate tourists and make Pompeii sustainable.
And so now, the archaeological team at Pompeii has found a way to maneuver tourists throughout the area. “Grande Pompei will be a ‘parco diffuso’ or scattered archaeological park, incorporating the archaeological areas of Pompeii itself, as well as villas at nearby Boscoreale, Oplontis (in the modern town of Torre Annunziata) and Stabiae, at modern Castellammare di Stabia,” CNN reported.
Italy’s culture minister, Gennaro Sangiuliano, told media it would be a “scattered museum” that is a “program of sustainable enhancement of the archaeological sites of the (archaeological) park and of the area around it,” per CNN. This means that even though sites used to be ticketed separately, they will bundled together with a shuttled service connecting the sites together.
The future is looking bright for the ancient city, once covered in ashes. What new discoveries will bring is uncertain, but what is known is the preservation of Pompeii has propelled knowledge about the ancient world forward.
The Two Plinys
Pompeii, with Vesuvius towering in the background
Pliny the Younger
These events and a request by messenger for an evacuation by sea prompted the elder Pliny to order rescue operations in which he sailed away to participate. His nephew attempted to resume a normal life, continuing to study and bathe, but that night a tremor woke him and his mother, prompting them to abandon the house for the courtyard. At another tremor at dawn, the population abandoned the village. After a third tremor, "the sea seemed to roll back upon itself, and to be driven from its banks", which is evidence of a tsunami. There is, however, no evidence of extensive damage from wave action.
A black cloud obscured the early light through which shone flashes, which Pliny likens to sheet lightning, but more extensive. The cloud obscured Point Misenum near at hand and the island of Capraia (Capri) across the bay. Fearing for their lives, the population began calling each other and moving back from the coast along the road. Pliny’s mother requested him to abandon her and save his own life, as she was too fleshy and aged to go further, but seizing her hand, he led her away as best he could. A rain of ash fell. Pliny needed to shake off the ash periodically to avoid being buried. Later that same day, the ash stopped falling, and the sun shone weakly through the cloud, encouraging Pliny and his mother to return home and wait for news of Pliny the Elder. The letter compares the ash to a blanket of snow. The earthquake and tsunami damage at that location were not severe enough to prevent continued use of the home.
Pliny the Elder
Vesuvius, active volcano that rises above the Bay of Naples on the plain of Campania in southern Italy. Its western base rests almost upon the bay. The height of the cone in 2013 was 4,203 feet (1,281 metres), but it varies considerably after each major eruption. At about 1,968 feet (about 600 metres), a high semicircular ridge, called Mount Somma, begins, girding the cone on the north and rising to 3,714 feet (1,132 metres). Between Mount Somma and the cone is the Valle del Gigante (Giant’s Valley). At the summit of the cone is a large crater about 1,000 feet (about 305 metres) deep and 2,000 feet (about 610 metres) across; it was formed in the eruption of 1944. More than two million people live in the vicinity of Vesuvius and on its lower slopes. There are industrial towns along the coast of the Bay of Naples and small agricultural centres on the northern slopes.
Vesuvius probably originated somewhat less than 200,000 years ago. Although a relatively young volcano, Vesuvius had been dormant for centuries before the great eruption of 79 that buried the cities of Pompeii, Oplontis, and Stabiae under ashes and lapilli and the city of Herculaneum under a mudflow. The writer Pliny the Younger, who was staying at a place west of Naples, gave an excellent account of the catastrophe in two letters to the historian Tacitus. Between the years 79 and 1037, several eruptions were reported, which include those occurring in 203, 472, 512, 685, 787, 968, 991, 999, and 1007. The explosions of 512 were so severe that Theodoric the Goth released the people living on the slopes of Vesuvius from payment of taxes.
How volcanoes work, explained by a volcanologist
Volcanologist Janine Krippner dives into the details of how volcanoes work and the different types of lava flows.
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After some centuries of quiescence, a series of earthquakes, lasting six months and gradually increasing in violence, preceded a major eruption that took place on December 16, 1631. Many villages on the slopes of the volcano were destroyed, about 3,000 people were killed, the lava flow reached the sea, and the skies were darkened for days. After 1631 there was a change in the eruptive character of the volcano, and activity became continuous. Two stages could be observed: quiescent and eruptive. During the quiescent stage the volcano’s mouth would be obstructed, whereas in the eruptive stage it would be almost continuously open.
Watch buildings crumble during the volcanic eruption of Italy’s Mount Vesuvius in 1944
In 1944, after a long period of dormancy, Italy’s Mount Vesuvius erupted, causing great destruction.
Between 1660 and 1944 several of these cycles were observed. Severe paroxysmal (suddenly recurring) eruptions, concluding an eruptive stage, occurred in 1660, 1682, 1694, 1698, 1707, 1737, 1760, 1767, 1779, 1794, 1822, 1834, 1839, 1850, 1855, 1861, 1868, 1872, 1906, 1929, and 1944. The eruptive stages varied in length from 6 months to 30 years. The quiescent stages varied from 18 months to 7 years.
Scientific study of the volcano did not begin until late in the 18th century. An observatory was opened in 1845 at 1,995 feet (608 metres), and in the 20th century numerous stations were set up at various heights for making volcanologic measurements. A large laboratory and a deep tunnel for seismo-gravimetric measurements were also built.
The slopes of Vesuvius are covered with vineyards and orchards, and the wine grown there is known as Lacrima Christi (Latin for “tears of Christ”); in ancient Pompeii the wine jars were frequently marked with the name Vesuvinum. Higher up, the mountain is covered with copses of oak and chestnut, and on the northern side along the slopes of Mount Somma the woods proceed to the very summit. On the western side the chestnut groves give way above 2,000 feet to undulating plateaus covered with broom, where the crater left by the great eruption of the year 79 has been filled in. Still higher, on the slopes of the great cone and on the inner slope of Mount Somma, the surface is almost barren; during quiescent periods it is covered by tufts of meadow plants.
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The soil is very fertile, and in the long period of inactivity before the eruption of 1631 there were forests in the crater and three lakes from which pasturing herds drank. Vegetation on the slope dies off during eruptive periods because of the volcanic gases. After the eruption of 1906, forests were planted on the slopes in order to protect inhabited places from the flows of mud that usually occur after violent eruptions, and in the fertile soil the trees grew rapidly.
In 73 the gladiator Spartacus was besieged by the praetor Gaius Claudius Glaber on the barren summit of Mount Somma, which was then a wide, flat depression walled by rugged rocks festooned with wild vines. He escaped by twisting ropes of vine branches and descending through unguarded fissures in the rim. Some paintings excavated in Pompeii and Herculaneum represent the mountain as it looked before the eruption of 79 , when it had only one peak.
The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Meg Matthias.
Nature of the eruption
Pliny the Younger wrote:
Pompeii and Herculaneum, as well as other cities affected by the eruption of Mount Vesuvius. The black cloud represents the general distribution of ash, pumice and cinders. Modern coast lines are shown; Pliny the Younger was at Misenum.
The eruption is considered primarily phreatomagmatic, i.e. a blast driven by energy from escaping steam produced by seawater seeping into the deep-seated faults and interacting with hot magma.
Timing of explosions
The authors suggest that the first ash falls are to be interpreted as early-morning, low-volume explosions not seen from Misenum, causing Rectina to send her messenger on a ride of several hours around the Bay of Naples, then passable, providing an answer to the paradox of how the messenger might miraculously appear at Pliny’s villa so shortly after a distant eruption that would have prevented him.
Inside the crater of Vesuvius
Date of the eruption
Since at least the late 18th century, a minority among archaeologists and other scientists have suggested that the eruption began after August 24, during the autumn, perhaps in October or November. In 1797 the researcher Carlo Rosini reported that excavations at Pompeii and Herculaneum had uncovered traces of fruits and braziers indicative of autumn, not the summer.
Casualties from the eruption
The casts of some victims in the so-called "Garden of the Fugitives", Pompeii.
The skeleton called the "Ring Lady" unearthed in Herculaneum
Herculaneum, which was much closer to the crater, was saved from tephra falls by the wind direction but was buried under 23 metres (75 ft) of material deposited by pyroclastic surges. It is likely that most, or all, of the known victims in this town, were killed by the surges, particularly given evidence of high temperatures found on the skeletons of the victims found in the arched vaults on the seashore and the existence of carbonised wood in many of the buildings. These people were concentrated in the vaults at a density as high as three per square metre and were all caught by the first surge, dying of thermal shock and partly carbonised by later and hotter surges. The vaults were most likely boathouses, as the crossbeams overhead were probably for the suspension of boats used for the earlier escape of some of the population. As only 85 metres (279 ft) of the coast have been excavated, more casualties may be waiting to be unearthed.
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Tension among residents has remained high because scientists don’t know for sure what’s going on under the surface. The scientific community agrees that the tremors and uplift are signs that the volcano is awakening. But they are struggling to rectify two competing explanations for the bulging ground that have been debated for decades, leaving residents and researchers uneasy. An answer to the geological mystery could bring scientists much closer to determining how likely the volcano is to blow. It could also provide geologists worldwide with warning signs they could look for when other big volcanoes start rumbling, especially supervolcanoes such as Yellowstone in the northwestern U.S., Toba in Indonesia and the Altiplano-Puna volcanic complex in Argentina, Bolivia and Chile.
One model—let’s call it the shallow magma model—posits that the seismicity and bulging are caused by magma pushing to break through the surface, making an explosive eruption, with violent magma outflow highly likely in the near term. Alternatively, in the hot fluids model, steam and hot gases released by magma located deeper underground are to blame. In that case, the ongoing seismic activity could stop abruptly or peak in a phreatic eruption—the volcano would spurt out hot liquids, gases and rock fragments instead of lava. This would pose a lesser threat, although it would still be a lethal one because so many people live close by.
“Everyone agrees that magma is involved,” says Roberto Moretti, an associate professor of geochemistry and volcanology at the University of Campania Luigi Vanvitelli in Italy, and a proponent of the hot fluids model since 2013. But scientists disagree on what role magma plays exactly and consequently how close it is to the surface. “Hence the big question,” Moretti says. “Where is the magma?”
The volcano, known as Phlegrean Fields in English, comprises two dozen craters and other structures in an area 14 kilometers across. One third of it lies under the Tyrrhenian Sea, between the Italian mainland and the country’s island of Sardinia. The volcano has been active for at least 80,000 years. Its caldera—the depression created when emptying magma chambers cause the roof of a volcano to collapse—formed after two violent eruptions 39,000 and 15,000 years ago. The older one caused a volcanic winter in areas within 100 km, sent ash as far away as Russia and abruptly cooled the climate around the world.
After its most recent eruption in 1538 the volcano went quiet. By now, “any previous connection between the molten rock underground and the surface has been sealed up,” says Christopher Kilburn, a volcanology and geophysical hazards professor at University College London. As a result, the crust serves as a barrier, and Kilburn says that before another eruption can take place, the crust has to be ruptured, creating a new pathway for lava or fluids to breach.
Scientists think that has been happening since Campi Flegrei awakened in the 1950s. At that time modest seismicity picked up, paired with the slow flexing—uplift and sinking—of the ground. Scientists say pressure from below the top part of Earth’s crust pushes against it at a depth of two to three km, causing it to stretch and fracture, creating superficial earthquakes and the surface bulge. Between 1982 and 1984 the ground rose 1.8 meters, and some 30,000 people were evacuated in what many scientists consider an aborted eruption—magma is thought to have ascended close to the surface, only for something to then halt its rise. The ground began deflating again until 2004, when the current uplift began.
According to a 2023 paper co-authored by Kilburn in Communications Earth & Environment, each uplift episode stretches the crust further, creating conditions more favorable to a rupture and opening a pathway for an eruption.
But that’s where the division lies. According to the shallow magma model, rising magma is piling pressure on the crust, which happened when the ground rose in the 1980s. According to the hot fluids model, which has gained more traction since seismicity picked up in the area in 2016, the magma sits deeper, but it is sending larger and larger quantities of steam and hot gases toward the surface.
Finding definitive evidence for either model remains elusive. Geophysicists lack direct access to the complex underground phenomena that they study. Instead they analyze the indirect signals of those processes that reach the surface, such as seismicity, ground uplift and gases emitted by vents called fumaroles. “That’s not unique to Campi Flegrei,” Kilburn says. “Whenever a volcano reawakens, we all have to use a little bit of imagination to work out what the signals mean.” Moretti likens the efforts of volcanologists to those of the physicians of the past who tried to discern human diseases only from a person’s symptoms, without having detailed knowledge of internal bodily processes.
Moretti and Kilburn, among others, note that the uplift has so far been slower than in 1982–1984, when it was likely caused by magma rising at shallow depth, which hasn’t really been seen in the current circumstances. The hot fluids model would be consistent with the large quantities of carbon dioxide measured at fumaroles and the shape of the ground’s bulge, which is greater at the epicenter, close to the town of Pozzuoli, Italy, and gradually decreases from there.
The one investigation scientists could conduct is to drill. “Boreholes are the most efficient and direct way to study geology and volcanoes,” says Giuseppe De Natale, research director at Italy’s National Institute of Geophysics and Volcanology, who agreed to speak to Scientific American as an individual researcher, not a representative of the institute. De Natale led efforts to drill a 500-meter pilot borehole in 2012 that provided scientists with more precise stratigraphical information about the origins and boundaries of the caldera. But he says that local politicians and media, together with a local scientist, began to “wage war” on the project by describing it as dangerous. Public opinion turned against a second, 3.5-km borehole, causing funders to pull their support.
It’s unclear whether support for new boreholes has increased now that the threat seems greater. De Natale says news of new drilling would likely cause a similar reaction, so right now drilling initiatives have been shelved. A 3.5-km borehole would take about a month to drill. It would have a diameter between 30 and 35 centimeters close to the surface and 10 to 12 cm at deeper levels. One such borehole would inevitably pierce Earth’s crust, but De Natale says that would pose few risks to local residents because modern boreholes are equipped with blowout preventers—mechanical devices also used in oil wells that monitor and seal the boreholes when pressure exceeds a certain threshold. Moretti says drilling could generate seismicity, and hot, acidic fluids could spurt out—as they do in geysers.
Boreholes would allow scientists to study deep geochemical compounds, as well as rocks, including their temperature and pressure. Additionally, boreholes would help researchers understand how much more the crust can stretch. “We know that the ground rose four meters since 1950 and 1.17 meters since 2005—but we don’t know how much more pressure the rocks can bear,” De Natale says. Four meters of uplift could be moderate, he says, or it could be close to the critical point of an imminent eruption.
Kilburn says the differences among scientists could sound like nitpicking to people on the caldera, because as long as the uplift continues, pressure underground will build, and seismicity will continue to increase. Yet De Natale says stronger earthquakes could also mean that fractures are taking place underground, allowing some of the pressure to ease. A similar trend appears to have occurred at the end of October, when the number of tremors under Campi Flegrei decreased. But De Natale says the trend might be short-lived: “Fractures heal over time, and when they close, pressure begins building again,” he says. Something similar happened in 2013, when seismicity appeared to drop only to pick up after a year. “It seemed as if it were all over,” De Natale adds. “But it all started again, just like before.”