Gravity pulls mount Etna to the sea, increasing the risk that the slope of an active volcano sooner or later will be destroyed.
There is no indication that such a collapse is inevitable, but new research shows that the South-Eastern side of Italian volcano moves over the land and in the sea, informs Rus.Media.
This movement means that the risk of slope collapse is higher than previously thought, the researchers report today (10 October) in the journal Science Advances.
“We need to better understand how this movement works, and what steps bring us closer to collapse,” says Morelia Urlaub, researcher of marine geodynamics at GEOMAR research Center ocean in Germany.
Mount Etna is the most restless volcano in Europe. This mountain is experiencing strong periods, beginning about 6000 RR. BC, and currently, there is a period of eruption, which lasts from September 2013.
Researchers, using satellite data and GPS measurements, also recorded that the South-Eastern slope of mount Etna is moving in the direction of the sea for over 30 years. In March, scientists from the Open University in the United Kingdom reported that in the period from 2001 to 2012, this slope was moving on average about half an inch (14 millimeters) annually.
There are disputes about whether this is a result of the displacement of the circulation of magma moving inside the volcano caused by the force of gravity. Mount Etna is constantly spewing lava on its slopes, and its rising weight increases the force of gravity. the material on the slopes, she said, the power gravitates to the new material down. The broadening of the base is typical of large volcanoes.
The foot of mount Etna, is immersed in water. The slopes of the mountain down below cichlasoma the coast and go deep in the Mediterranean sea. To date, no data on the movement of mountains below sea level.
Using a network of sensors seabed, Urlaub and his team measured how the sound goes from point to point every 90 minutes between April 2016 and July 2017.
They found that during the eight-day period in may 2017 mark on the underwater slope moved up to 1.6 inches (4 centimeters). The offset was not in the earthquake; not because of a fault or seismic waves, but rather as the result of a gradual slide.
The area where the researchers recorded the offset is far from a reservoir of magma in the centre of Etna, reported Urlaub. This means that the movement was not the result of magma movement, which circulates in the underground chamber of the volcano. It is relentless work of gravity, which pulls the whole slope above and under water
This is bad news, since Etna is a real threat to human life.
From the geological history of the other volcanoes we know that they were catastrophically destroyed and has caused large, rapid landslides. If such shifts is out to sea, they can lead to devastating tsunami.
It’s only a hypothesis which still needs to prove scientifically. Scientific observations of the mountains being only a few decades, and the whole history of Etna exceeds 500 000 years. Need more monitoring to find out whether there are any changes in the movement of the slope and assess the risk of collapse.
“The danger exists,” said Urlaub. “It is very important to follow the slope of mount Etna and its movement.”