Experts from the National Research Institute for Geophysics and Volcanology (INGV) in Italy and University College London (UCL) conducted an investigation of the volcanic activities within the premises of Campi Flegrei volcano. Led by Professor Christopher Kilburn from UCL's Earth Sciences department, the researchers observed that this volcano is becoming more prone to rupture or fracture through the rock that comprises the body of the volcano, suggesting a possible eruption anytime soon.
How Active Is Campi Flegrei Volcano?
The Campi Flegrei volcano, located in southern Italy, is one of the remaining active supervolcanoes in the world. It falls under the supervolcano category because of its potential to create a magnitude eight eruption, resulting in the discharge of materials over 200 cubic miles away.
Its eight-mile-wide caldera, or the basin-like depression that resulted from a previous explosion, is the largest active caldera in Europe. It extends from the western part of the city of Naples to the Tyrrhenian Sea. One-third of the caldera is partially immersed in the Bay of Pozzuoli, while the remaining two-thirds is a densely populated area.
Its last eruption took place during the reign of King Henry VIII in 1538, following the volcanic activities that happened 3,000 years prior. Campi Flegrei is a large caldera that is home to about 360,000 residents. These people need to be evacuated if the experts sense an immediate threat of eruption.
If the anticipated disaster happens, it could be compared to the size of the eruption of Mount Vesuvius which destroyed the Roman cities of Pompeii and Herculaneum in AD 79. The people living in the vicinity of the volcano would be in danger as it expels pyroclastic currents which is described as solidified lava particles combined with hot and fast-moving gas flow.
READ ALSO: Italian Supervolcano Campi Flegrei Reportedly About To Erupt Soon; 360,000 People Affected
Warning Signs of an Impending Eruption
According to the researchers, large calderas like Campi Flegrei usually wait only several decades of inactivity before erupting again. What worries scientists is the fact that the volcano has remained restless since the middle of the 20th century. It showed two-year periods of activity in the 1950s, 1970, and 1980s which cause local shaking and ground uplift as the magma moves beneath the surface.
During the past decade, the ground underneath Pozzuoli creeps upwards at a rate of four inches annually. This is due to the bulging and deformation of the ground as a result of increased pressure in the magma coming from gas.
A possible eruption can be preceded by weak signs like fewer shakings and minimal ground uplift. Meanwhile, the immediate signal of an impending eruption is the formation of cracks in the ground and the release of dark streams of volcanic gases. As of now, the warning signs shown by Campi Flegrei have not yet reached this stage.
The current tensile strength of Campi Flegrei is almost about one-third of its measurement in 1984. This property refers to the maximum amount of stress that can be tolerated by a stretched material before it gets broken.
Experts at UCL used a model of volcano fracturing in interpreting the patterns of shaking and ground uplift. The images projected by the model suggest that some areas of the volcano have been stretched to a near breaking point.
Experts reported that it has become weaker and more prone to rupture, suggesting an increased likelihood of an impending eruption. However, they clarify that there is still no guarantee that an eruption will happen anytime soon.
Kilburn explains that a rupture naturally forms when a volcano is stretched as a result of pressure build up underground. Once a rupture has started, the fluids inside the volcano can escape easily. Although a rupture allows the opening of a crack through the Earth's crust, the magma still needs to be pushed up at the right spot before an eruption happens.
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