A magnitude 4 earthquake shook the Bárðarbunga caldera around 7am. Earthquakes of this magnitude occur regularly there. It is the second largest volcano in the country and one of the most active.
The epicenter of the earthquake was 4.6 kilometers northeast of Bárðarbunga at a depth of 1.3 kilometers. According to the measurements of the Institute of Meteorology, no significant seismic activity has been recorded since this quake. The last major disturbance around the volcano occurred in 2014, when magma erupted from the magma chamber below Bárðarbunga, and about 40 km further in Holuhraun there was a large volcanic eruption that lasted almost six months. If, however, an eruption occurred in the caldera itself beneath the glacier, its nature would be explosive and there is a high risk that it would be accompanied by large glacial flows and even catastrophic flooding.
Source: Yle