The surface bulge warns early volcanic eruptions

According to research results published in the Journal of Natural Geology on 12/1, the bulge of the ground before volcanic eruption may indicate the amount of ash sprayed into the sky.

During the study, a team of scientists from the Northern European Volcanic Center in Iceland's capital Reykjavik, led by Sigrun Hreinsdottir, installed sensors of the Global Positioning System (GPS). around the famous volcano Grimsvoetn of Iceland.

The data showed that, when Grimsvoetn operated in May 5/2011, the ground around it swelled.

During this short but intense eruption, Grimsvoetn created a column of dust and smoke up to 20 km high.

Photos: wired

By comparing the level of deformation of the ground with the amount of ash sprayed out, scientists have determined the conditions that often occur in magma basin (molten rock) , formed under the previous volcano. when an eruption occurs.

Magma basin is where molten rock is continuously pumped. When the pressure there is too high, magma will be released through the fault of the ground above, then become ash due to reduced heat during the air movement.

The eruption time and scale of the smoke column depend on a number of factors inside the magma basin such as magmatic mass, spraying force and elasticity of the stone walls inside the tank when the pressure increases.

According to research results, magma basin of Grimsvoetn volcano is about 3km in length. The signs below the ground show that if the pressure at a depth of 1.7 km decreases, about 1 hour after the volcano will erupt.

For volcanoes being closely monitored, this method can help warn of impending eruptions and predict the possible height of dust clouds.

Such an early warning will be very useful for the airline industry.

Grimsvoetn is located in the center of the largest Vatnajoekull glacier in Iceland and is also the country's most active volcano. It has erupted nine times since 1922 to 2004.

The eruption in 2011 has caused a lot of concern about possible air traffic chaos, like a year earlier when Eyjafjoell's nearby volcano erupted, causing the largest stagnation of aviation activity. from the second world war with about 100,000 flights and 8 million passengers were affected.