A volcanic catastrophe will occur in the Mediterranean Sea every 10,000 to 15,000 years!

Devastating earthquakes, explosions, tsunamis… the Mediterranean region is extremely active in terms of geodynamics. Beneath the blue waters, a real tectonic collision is taking place between several large plates. The symbol of this activity is Etna in Sicily, one of the most active volcanoes in the world. Although very impressive, its frequent eruptions pose no major threat to the population and its activity is much less intimidating than that of another volcano located in the Bay of Naples and whose recent seismic activity scares you awake.

4 major eruptions in 50,000 years, one of which may have contributed to the extinction of the Neanderthals

The Phlegmian Fields represent a supervolcano whose vast caldera bears witness to the violence of past eruptions. Another monster sleeps elsewhere in the area, out of sight, beneath the waters of the Tyrrhenian Sea. Seventy kilometers long, 30 wide and 3,500 meters high, these are the dimensions of Marseille, an underwater volcano that is part of the Aeolian Arc. If its current activity is relatively moderate, some recent manifestations have begun to worry experts. A large eruption could indeed have a major impact on the nearby and densely populated Italian coasts. However, the risk is difficult to estimate due to a severe lack of data related to the eruptive history of this volcano.

So a team of scientists deeply “scanned” the sea floor of the Marseille Basin with the aim of finding traces of this past volcanic activity. In sediments deposited over the past 50,000 years, scientists were able to observe four major volcanic deposits, each testifying to a catastrophic event. With a substantial thickness ranging from 10 to 25 metres, these strata composed of volcanic debris do not seem to be associated with the Marseille eruption! Drilling made it possible to date these deposits and thus trace the author of these major volcanic events.

A catastrophic eruption approximately every 10,000 to 15,000 years

Unsurprisingly, the data pointed to the Fleagrain Fields supervolcano. The ages of the deposits would be 36 ± 6 ka, 32 ± 7 ka, 18 ± 3 ka, and 8 ± 1 ka (ka stands for “kilo-year”, or 1,000 years). Given the margin of error, it appears that the two oldest deposits may be linked to a super-eruption that occurred about 39,800 years ago. An explosion that has also been classified as one of the most violent explosions ever to have occurred on Earth. This would indeed have plunged much of Europe and Asia into volcanic winter, and thus potentially contributed to the extinction of the Neanderthals.

The third deposit would correspond to an eruption that occurred 14,900 years ago. The large amount of volcanic material ejected is the origin of a rock known today as Neapolitan Yellow Tuff. The final deposits, still attributed to the same volcano, would have resulted from a small eruption.

Results published in magazine Geology Which point to a recurrence of destructive eruptions in this area of ​​the Mediterranean Sea every 10,000 to 15,000 years. Although these data provide a better understanding of the history and functioning of the Tyrrhenian Sea volcanoes, this apparent recurrence does not allow us to predict with certainty when a new super-eruption of the Phlegrean Fields might occur. Volcanoes remain unpredictable and only with increased monitoring will it be possible to predict their awakening even slightly.