Largest quake recorded: Volcanic tremors

A large earthquake struck just before 7 this morning. The earthquake is the largest at the volcano in Grímsvötn since the beginning of measurements. There are indications that a glacial outburst flood has started.

“We are looking at data from our office. There are indications that there has been a start to a flood in Grímsvötn, but we are waiting for further measurements to confirm,” Lovísa Mjöll Guðmundsdóttir, a natural hazard specialist at the Icelandic Met Office, tells us.

Aware of volcanic tremors

The earthquake measured 4.3 magnitude and originated at a depth of about 100 meters about 2 kilometers northeast of Mt Grímsfjall, according to Lovísa.

“We’re seeing volcanic tremors,” she added. Experts will then examine whether the water level has increased in Gígjukvísl.

The most active volcano and ready for eruption

Grímsvötn is by far the most active volcano in Iceland and for several years it has been considered ready to erupt again.

Land rise has been detected there for a long time and it has been thought that it is due to magma accumulation under the ground.

FLightcode from yellow and green again earlier this month

In 2020, the expansion of Mt Grímsfjall had reached the same level as before the last eruption, which happened in 2011. That eruption was large. Since then, the expansion has only increased.

The size of this eruption was actually surprising, as the expansion was about the same as before the 2004 eruption.

The flight colour code for Grímsvötn was upgraded to yellow earlier this month, after a small earthquake was detected at the volcano.

The code was lowered to a green day later, or Friday, January 5 .