A massive volcanic activity could happen sooner than scientists already estimated, as a new research published Wednesday suggests.
Experts previously believed that the last time the world experienced one of these gigantic eruptions was around 74,000 years ago, in Indonesia – the same Mount Agung that recently forced about 100,000 people to leave their homes in Bali. But this new research suggested that it was actually 20,000 and 30,000 years ago.
Scientists thought these eruptions could only happen between 45,000 and 714,000 years – an amount of time that the Professor Jonathan Rougier, a statistician and the lead researcher of the study, considered as “comfortably longer than our civilization.” However, this new result published in the Earth and Planetary Science Letters journal suggested that’s far from reality.
The researchers from the University of Bristol, using an eruption data called LaMEVE database, assured that this apocalyptic, volcanic super-eruption – able to destroy a significant part of an entire civilization living in a whole continent – could occur in the next 17,000 years.
Also, the team also said that the eruptions could occur as frequently as every 5,200 years.
“On balance, we have been slightly lucky not to experience any super-eruptions since then. It is important to appreciate that the absence of super-eruptions in the last 20,000 years does not imply that one is overdue,” said Jonathan Rougier, professor of statistical science. “What we can say is that volcanoes are more threatening to our civilization than previously thought.”
In comparison, a standard eruption could spread around 3,000 cubic kilometers full of rocks and ash. But these gigantic eruptions would be able to cover even the entire planet, changing the worldwide weather for several decades.
Enough ash to cover a continent
On one side of the study, the experts wrote that eruptions of around 100 million metric tonnes could happen with less frequency than previous research suggested. On the other side, the most massive eruptions of 1,000 gigatonnes or more could occur with far more frequency.
“The approach and assessment are robust, and certainly will help us understand and most importantly may help predict future eruptions,” said a Dr. Reichow from the University of Leicester, who was not involved in the study. “However nature, including volcanic eruptions, does not necessarily work as clocks work.”
Prof. Rougier also said that the technology and techniques used to determine the “average time between super-eruptions” can also be employed to change the “approach of seismologists looking at earthquakes.”
The researchers said that the largest eruption that happened in the last two million years was the Toba Caldera eruption, in Sumatra, Indonesia. According to them, the volcanic ash that threw away covered around 671 cubic miles (2,800 cubic km) throughout the atmosphere over the area.
That amount of ash would be enough to cover one half of the US.
The island located in the middle of the Lake Toba probably formed when the magma coming from the ground interacted with the water.