Focus on the south of Italy today, more precisely the region of Naples, and what is called the Phlegraean fields.
The Naples region of Italy, and what is known as the Phlegraean Fields, is a volcanic region located in the Gulf of Pozzuoli, northwest of Naples. Fields that correspond to one of the most active super-volcanoes in the world. Italian journalist Daniel Zappala, correspondent for the daily Avvenire in Paris, doctor in geography is the guest of European microphone.
franceinfo: The matter of the Phlegraean Fields, Naples, the Bay of Naples, and to the east of Naples there is Vesuvius. Everyone knows Vesuvius, but who knows the Phlegraean fields? Yet this is what threatens the entire region of the city of Naples?
Daniel Zappala: This is a fact that remains visible today in what is called a super volcano, namely a volcano whose potential power is truly beyond imagination. You just have to think that, about 30,000 years ago, according to scientists, the major eruption of the Phlegraean fields probably contributed to the extinction of Neanderthal man.
Today, over 100 km2 are located on these Phlegrean fields, two cities: Pozzuoli and Cumae. And then there is the famous caldera, the cauldron, and we see it on the map, it’s a cauldron with the bay, which is cut out in a semicircle, it’s a flat basin 13 km in diameter and there , it is more than a million inhabitants who are in danger, whether it is the cities of Pozzuoli and Naples?
A recent study by Neapolitan and London researchers has proven that, perhaps, and the next eruption of the Phlegraean fields is not so far away as we imagined, of course, it is not for tomorrow.
Because the Phlegrean fields are terrestrial volcanoes, but also underwater?
Submarines and in fact, of course, they are monitored every day, monitored. Each micro earthquake is scrutinized, and then we study the composition of the fumaroles, because there is hydrothermal activity, an activity in terms of gases that are emitted, which is permanent, and depending on the composition of these gases, in particular the concentration of carbon monoxide or dioxide, we can assess whether there is in fact a phenomenon of energy accumulation, under the earth’s crust, and suddenly, this is what we have observed since the 1950s , and that’s what raised the alarm. There is not only what is visible, namely in fact land upheavals which are spectacular, in the 1970s, imagine it was in fact a two-metre uplift.
But in addition, there is this accumulation of gases which make the temperatures rise, a few tens of kilometers in the basement, and therefore there is an accumulation of energy. There is a risk that is higher, compared to previous assessments.
Et the Italian government has put in place an evacuation plan for the population…
Of course, we must not forget that Naples has long been the most populated city in Europe. Here, we are in a place that is potentially extremely dangerous, we have an incredible concentration of population, because historically these volcanic phenomena have also given fertile soils.
The fields are several terrestrial and underwater volcanoes, there is one called the Solfatara, the Soufrière?
Yes there are in fact these phenomena of gas emanation, therefore the fumaroles which give this sulphurous side; this allows scientists to really measure indirectly, what is the level of energy which, little by little, evolves at the level of the basement.
And so this plan of the Italian government of the region of Naples, with more than a million people to evacuate?
Of course, this is actually an actual Sword of Damocles. And at the same time, the authorities don’t want to be overly alert either, of course, because we don’t really have a time scale, even according to the most recent studies on the moment of the next eruption.
To read
Eruption with witnesses, the birth of Monte Nuovo, Italy, 1538 by Brice Gruet, Presses Universitaires editions, Blaise Pascal.