What's happening to the volcano in Italy. When will Campi Flegrei erupt? How were the Phlegrean fields formed?
An international team of scientists from Italy and the USA conducted a study and determined the exact location of the magma bubble under the Phlegrean Fields. According to scientists, molten rocks lie beneath the port city of Pozzuoli in southern Italy and create pressure that could intensify the eruption to catastrophic proportions. This was reported in a press release on Phys.org.
According to researchers, the supervolcano is becoming more and more dangerous. A particular danger is that no one can say exactly when the next eruption will occur. In this case, there is a possibility that the magma will find a way out at the bottom of the sea and no catastrophe will occur.
Let us remind you that the Phlegrean Fields are a volcanic area located in Italy near the city of Naples. The super eruption of the Phlegrean Fields occurred about 40 thousand years ago and probably led to the onset of a volcanic winter. Ashes covered an area of about 1.1 million square meters. km.
In the 1980s, a number of weak earthquakes occurred in the area of the Phlegrean Fields. Then the eruption did not happen, but the hot rocks caused deformation of the lithosphere and an increase in pressure.
Phlegrean Fields is a district of the city of Naples, located on the shores of the Gulf of Pozzuoli. The Phlegrean Fields are located in the northwestern part of the city, bordered in the west by Cape Miseno, and in the east by Cape Posillipo. The coastal strip of the Tyrrhenian Sea is clearly visible from the mountains. The Phlegrean fields cover an area of 100 square kilometers. Today, this area is connected to the central part of the city via a metro line.
Supervolcano on the Phlegrean Fields today
Recently, frequent reports have appeared on the Internet and in the media that a supervolcano is coming to life in the Phlegrean Fields. You can often find headlines like this in newspapers: “A volcanic eruption will soon occur in the Phlegrean Fields of Naples!” Is it really?
Volcanologists, unfortunately, confirm such reports. Their opinion is based primarily on the fact that the volcano is beginning to show signs of activity, the temperature of the volcano is constantly increasing, and this may mean, as experts say, that magma will soon reach ground level. It is assumed that the magma chamber of this volcano is connected with the chamber of Vesuvius, the most dangerous volcano in the entire history of mankind. The degree of danger is constantly increasing, as scientists say, if an eruption occurs, it will have serious consequences, first of all, for densely populated city, as well as for the whole of Europe. If the ground continues to rise further, the city will have to be evacuated.
History of the volcano on the Phlegrean Fields
It is believed that the first eruption of the volcano occurred 39 thousand years ago. Some researchers suggest that this is what contributed to the migration of Neanderthals to the eastern part of the Mediterranean Sea. Scientists believe that during that eruption, about 300 cubic kilometers of ash, mixed with large amounts of fluorine, chlorine, and sulfur dioxide, were thrown into the atmosphere.
The volcano became especially active in 1970, when 10,000 people were evacuated. local residents who never returned to their homes. A few months after the evacuation, the coastal part of the city was completely submerged into the sea to a depth of 10 meters. Thanks to the fact that people heeded the warnings of the authorities in time, they were able to avoid disastrous consequences.
There are no reasons for special concerns yet. People living at the foot of the volcano in Naples need to regularly monitor the research of volcanologists, and in case of a threat, be prepared for urgent evacuation.
The Italian supervolcano Phlegrean Fields is one of the most dangerous in the world, not least because more than a million people live around it.
A new study, published in Scientific Reports, has identified the source of the magma that fuels the dormant and ominous cauldron. Unfortunately, this volcano is more dangerous than previously thought.
Search for the supervolcano's hot zone
Typically, scientists use the seismic waves that magma emits as it travels through the crust to determine where it is currently located. But because the supervolcano has remained generally quiet since the mid-1980s, finding its source of magma is much more difficult. 
An international team led by specialists from the University of Aberdeen attempted to solve this riddle. Using specialized mathematical analysis of seismic data collected since the mid-1980s, the team identified a hot zone at a depth of 4 km beneath Pozzuoli, near Naples. 
According to the results of the study, the hot zone is either not a large number of magma, or the molten top of a massive magma chamber whose liquid fire spreads deep below the earth's surface. Either way, scientists have found compelling evidence of an active heat source that supplies magma to one of the world's most dangerous volcanoes. But the story doesn't end there. 
Rising ground level above the caldera
One of the key mysteries of the Phlegrean Fields is their periodic and frightening growth. Between 1982 and 1984, the ground in the crater rose 1.8 meters. Whatever the cause - magma, gas moving through the earth's crust, or the movement of superheated water - the crater soon sank.
New research helps explain why this growth did not end with a volcanic eruption. Seismic imaging shows that the magma's eruption to the surface was prevented by a very rigid, shallow rock formation located above it. This is why the magma spread laterally and was unable to break through. 
This means that the risk from the caldera has migrated. "The Phlegrean Fields can now be compared to a pot of boiling soup beneath the surface," says lead author Dr Luca de Siena, a geologist in Aberdeen. 
This means that instead of a single eruption point, a new caldera may form. 
How were the Phlegrean fields formed?
The Phlegrean Fields remains a monster that scientists understand very poorly. The caldera was formed 40 thousand years ago during one of the most energetic paroxysms of the last few million years. At that time, the supervolcano ejected about 500 cubic kilometers of debris, which could even reach Greenland, despite a distance of 4,600 kilometers. 
There have been several eruptions since then, but it has left most of the fireworks to volcanoes located near or within the crater itself, such as Vesuvius and the ominous sulfurous Solfatara. Volcanologists remain acutely aware of the risk to the 6 million people living in the monster's "blast zone" and are therefore constantly monitoring it. 
Should we be afraid of a new eruption?
What's really worrying is that the Phlegrean Fields are growing again, although the risk of an eruption is now 24 times lower than in the early 1980s. As always, volcanologists don't know what's really going on, but they believe the volcano is reaching a critical point where an eruption is imminent. 
Regardless of whether the eruption results in a new caldera or a regular eruption, de Siena is confident that the volcano is becoming increasingly dangerous. 
Forget Yellowstone. Phlegraean Fields is a supervolcano that's really worth worrying about.
Almost all calderas on our planet are potentially dangerous. But if we talk a lot about Taupo or Toba, then Campi Flegrei in Italy for some reason is deprived of attention. In fact, it poses no less a threat than its overseas “brothers”, and can lead to a major catastrophe that will destroy a significant part of Europe. Understanding what is happening to the Italian caldera could be vital in helping to avoid the consequences of its activity in the future.
The last eruption in the subvolcanic system of Campi Flegrei occurred only 477 years ago - in 1538. The amount of volcanic material ejected from the caldera was enough to form the hill of Monte Nuovo near the city of Pozzuoli. Signs of its earlier destructive activity have survived to this day - the fumarole fields of Solfatara with hydrogen sulfide springs and the famous Roman columns of the “Temple of Serapis”, indicating the flooding of the region along the Gulf of Pozzuoli.
Campi Flegrei remains active today, so the National Institute of Geophysics and Volcanology of Italy (INGV) closely monitors its activities. The data obtained over the past few decades is disappointing. From 1982 to 1985, the surface of the caldera rose to a height of about 2 meters in just 3 years. In 1983, the city center of Pozzuoli - Rione Terre - suddenly rose and then fell again. Then about 10 thousand people were forced to leave their homes and were never able to return, since access to this zone is now prohibited.
Since the beginning of 2012, the surface of Campi Flegrei in the Pozzuoli region has been growing by about 6 cm per year. Although these figures are not as impressive as in the 1980s, they raise serious concerns among volcanologists. According to a report from the Vesuvius Observatory published on July 21, 2015, temporary increases in growth occur from time to time in the Phleugrean Fields. For example, in January 2014 alone, the ground rose by 8.5 cm, and in March 2015 - by 3 cm. In total, over the past 4 years, the growth of the caldera surface was 24 cm.
At the end of 2012, severe deformation of the Bocca Grande crater was recorded on the fumarole fields of Solfatara, and over the past few years a large number of tremors have been recorded in the caldera, mainly off the northern shores of the Gulf of Pozzuoli at a depth of 1–4 km. In particular, for Last year 119 earthquakes occurred here. Moreover, since 2003, the temperature of water and steam in the volcano’s fumaroles has risen by 10–15 °C, and the composition of the released gases has become more “magmatic,” that is, with a higher content of carbon dioxide.
What does all of this mean? According to the conclusions of volcanologists, such a situation may indicate, firstly, a further rise of magma, which began in the 1980s. Secondly, this may be due to changes occurring in the hydrothermal system of the volcano. And thirdly, activity may increase due to the appearance of new magma in the bowels of Campi Flegrei. In combination with rising ground, changes in the composition of gases and an increase in temperature in the fumaroles, the latter hypothesis seems the most likely.
Considering that major changes in the 1980s did not lead to an eruption, one can only hope that the current situation will not affect the activity of the volcano. Scientists are still trying to answer the question of when the explosion of Campi Flegrei will occur. This year they drilled into the caldera and installed monitoring instruments at great depths. But for now the future of the Phlegrean Fields remains a mystery.
The magma underneath has already created the necessary pressure and temperature, after reaching which a powerful eruption could cover the territories of a number of European countries at once.
Researchers from Italy and France have concluded that the supervolcano that rendered a third of Europe temporarily uninhabitable 39,000 years ago is close to another mega-eruption. The exact date cannot yet be given, but the information is significant and indicates the need for close monitoring of this quite dangerous place. The corresponding article was published in Nature Communications (http://www.nature.com/articles/ncomms13712).
Scientists used modeling of processes leading to particularly violent eruptions. Before they happen, magma rising through the earth's crust hits a "lid" at the top. When the threshold pressure is reached, the rocks that make up the “lid” undergo a sharp change. The compounds that make up the magma decompose, releasing the water bound in them. Superheated water vapor immediately begins to heat the surrounding crustal rocks, reducing their strength. After this, the “lid” collapses and the erupting fountain of hot gases scatters debris and ash over a huge distance.
Having modeled how such processes occur in the area of the earth's crust near Naples, where the Phlegrean fields are located, scientists came to the conclusion that now the magma there is close to critical pressure, after which it will trigger the process of avalanche-like destruction of the “lid”. This means that a new eruption here will happen quite soon by geological standards. It is still difficult to specify its timing more precisely, since it is impossible to directly study these processes, and in order to create more accurate models, it is necessary to record more parameters of mega-eruptions of this kind. So far, humanity has encountered only two - 39,000 and 70,000 years ago. And most of their witnesses died from lava spills and ashfall.
39,000 years ago, the volcano that was on the site of the modern Phlegrean Fields had already erupted according to the pattern described above. Then it simply blew up, and now only a slight depression remains in the place of the former huge mountain. Emissions of ash and stones covered an area of more than 1.1 million square kilometers with a thick layer - from Southern Italy to the modern Black Sea region, Donbass and the Caspian Sea. All the way to Romania, the ash layer reached almost a meter. Where vegetation was not completely destroyed, its growth was significantly inhibited.
Volcanic rock particles in the stratosphere greatly scattered sunlight, leading to a string of cold years. The bulk of what was then Europe was already a fairly cool paleotundra. In the absence of even moderate summer warming, the growth of green plant mass stopped, and the lack of light interfered with photosynthesis. Therefore, those animals that did not die during the “rain” from the ashes left a significant territory from Italy to the Urals. The Neanderthals who lived here previously also ceased to be found in this part of the European continent 39,000 years ago. They survived only in Spain, where the ashes did not fall due to the winds.