Over 4,500 Earthquakes Hit Iceland as Volcano Shows Sign of Eruption

A large earthquake swarm that has so far seen over 4,500 quakes recorded has hit Iceland. The swarm began on 19 June, with thousands of small earthquakes striking near the village of Siglufjördur, in the north east of the country.

Officials at the Iceland Meteorological Office (IMO) said three of the earthquakes in the swarm measured above magnitude 5. The largest was on June 21, when a magnitude 5.8 hit about 18 miles from Siglufjörður. In a statement released June 23, the IMO said seismic activity is ongoing and there is a chance more earthquakes will hit the area.

The swarm was felt across northern Iceland, with the IMO even getting reports as far as the capital of Reykjavik. The magnitude 5.4 and 5.6 earthquakes on June 20 appeared to trigger landslides and falling rocks near the epicenter, but events like these have taken place in the past, with steep slopes in the region.

No damage to property has been reported, although some people said small items fell from shelves as a result of the earthquakes. On June 22, the IMO said it expects the swarm to continue over the coming days and that a larger earthquake, measuring magnitude 6 or above, cannot be ruled out. However, it said "in most cases" the seismic activity will come to an end without any more significant quakes.

The earthquake swarm follows a report by the IMO that the Grímsvötn volcano in toward the south, one of the country's most active, could be about to erupt. The earthquake swarm is not connected to the unrest recorded at the volcano.

On June 16, the IMO said a team of scientists had met to discuss the increased activity at Grímsvötn observed since January. The volcano last erupted in 2011 and caused disruption to flights across Northern Europe, with the IMO describing it as a "fairly large and powerful event."

In between eruptions, magma accumulates and pressure in the volcanic system builds. Over recent weeks, scientists have noticed an increase in sulfur dioxide near to where the last two eruptions took place. "This is the first time that we measure so much [sulfur dioxide] at a volcano in Iceland that is not in an eruptive phase and its presence is indicative of magma at shallow level," Melissa Anne Pfeffer, a specialist at the IMO, said in a statement.

There has also been a notable increase in geothermal activity at the volcano.

Unrest at Grímsvötn started six months ago, with total uplift in the area measuring 4.7 inches. Seismic activity picked up at the end of May, with 2,000 earthquakes detected since then. The IMO said pressure in the magma chamber beneath the volcano is comparable to the last eruption.

The IMO will now closely monitor the volcano with the Institute of Earth Sciences, Iceland Geosurvey and geothermal power station HS-Orka.

Grímsvötn volcano
An eruption at Grímsvötn volcano in 2011. Scientists say the volcano may be about to erupt again. NordicPhotos /Getty Images