Campi Flegrei — the giant caldera system located west of Naples, in southern Italy — may not be as dormant as we think. According to a study just published in Science Advances, the ancient supervolcano has a rhythm to its hellish outbursts — and the music may have just started.
This is not to say that Campi Flegrei is about to burst in the near future. The sleeping giant poses no immediate threat to the 1.5 million people living in the Naples region, notes Science Alert.
However, it seems that the massive eruptions that raged at Campi Flegrei during the supervolcano’s long history fit a certain pattern — which may have started to unfold once more. The recent findings suggest that the volcano may be building up magma deep under Earth, which points to “the beginning of a new caldera cycle at Campi Flegrei,” the authors write in their paper.
“We propose that the subvolcanic plumbing system at Campi Flegrei is currently entering a new build-up phase, potentially culminating, at some undetermined point in the future, in a large volume eruption.”
A Volatile History
Also known as the Phlegraean Fields, Campi Flegrei is one of the few active supervolcanoes in the world. The imposing caldera system “is the largest volcanic feature along the Bay of Naples, which is also home to the more famous Vesuvius,” notes NASA.
The massive volcanic cluster — literally named “Fiery Fields” — consists of 24 craters and volcanic edifices (the iconic cone-shaped structure of a volcano, built from an accumulation of lava around an underlying vent). Although most of Campi Flegrei lies hidden beneath the waters of the Gulf of Naples, a large portion of the caldera is situated at ground level, which means you can walk right into it.
Adventurous hikers trekking the caldera can spot some of the many fumaroles pockmarking the supervolcano — openings in the Earth’s crust from where smoke billows out. For instance, the photo below captures a fumarole at Campi Flegrei’s Solfatara volcano — a volcanic crater that also emits sulfurous gases.
Although the area exudes a captivating, wild beauty, Campi Flegrei may actually be the most dangerous volcano on the planet, according to Discover magazine. Its troubled history is marked by two violent “super-eruptions” ranking among the largest volcanic explosions to occur in Europe in the past 40,000 years.
The first one, known as the Campanian Ignimbrite eruption, shook the Earth some 39,000 years ago, dispersing ash over an estimated area of about 1.4 million square miles. The mega-eruption plunged the planet into a “volcanic winter” and may have been responsible for a major global extinction event that possibly wiped out the Neanderthals, the Inquisitr previously reported.
The second “super-eruption” of the Campi Flegrei caldera occurred roughly 15,000 years ago and is called the Neapolitan Yellow Tuff eruption — named after the yellow tuff rock exposed by the blast.
The Recent Past
The most recent volcanic eruption at Campi Flegrei was considerably milder and happened almost 500 years ago. This latest explosion led to the formation of a new mountain dubbed Monte Nuova — forged from burning lava spewed over the course of eight days.
Around 20 other similar “tame” eruptions have been recorded in the supervolcano’s long history, going back 60,000 years. After examining material leftover from all these events, including the two mega-eruptions that re-shaped the caldera, the volcanologists discovered a hidden secret in the chemical composition of the crystallized magma.
As it turns out, the chemistry of the volcanic rocks described a specific pattern — hinting that the eruptions follow a certain cycle. And, since the material that settled after the latest eruption also appeared during a few other minor events in the supervolcano’s past, the team inferred that the cycle may have just restarted.
Similar to the Monte Nuova eruption, these events also produced gassy, water-saturated magma rich in carbon dioxide. The notable thing about these particular events is that they occurred shortly before the Campanian Ignimbrite and Neapolitan Yellow Tuff eruptions, the authors write in their paper.
“Our data reveal that the most recent eruption of Monte Nuovo is characterized by highly differentiated magmas akin to those that fed the pre-caldera activity and the initial phases of the caldera-forming eruptions.”
“We suggest that this eruption is an expression of a state shift in magma storage conditions, whereby substantial amounts of volatiles start to exsolve in the shallow reservoir,” adds the team, arguing that this “may indicate that a large magma body is currently accumulating underneath Campi Flegrei.”
Does this mean that the supervolcano is cooking up a new massive eruption? Not necessarily, says study lead author Francesca Forni, a volcanologist at Nanyang Technological University in Singapore
“We actually don’t know for sure what the next step is going to be,” Forni told the National Geographic, explaining that the magma could either ignite in a new build-up cycle or cool down and resume its slumber.
As she points out, the chemical analysis of the last eruption “indicate[s] that the magmatic reservoir might be ‘ready’ for accommodating magmas from recharge without erupting frequently.”