Iceland Quakes Spread to Second Volcano

Significant seismic activity has been occurring between Iceland's Barðarbunga volcano and Askja volcano, which are only about 30 miles apart. A number of heavier magnitude earthquakes have rocked the region since last night, and Icelandic officials have been reporting ongoing earthquake swarms.

According to the Icelandic Meteorological Office (IMO), last night's events began with a 5.3-magnitude earthquake around Barðarbunga a quarter after midnight. This signaled countless tinier earthquake swarms ranging between magnitude 2 and 3 that have intermittently continued into this morning.

Just before 2 p.m. (GMT), the IMO identified a 4.5 magnitude event just east of the Askja caldera - a new location for these worrying events to spread. The Askja volcano is about 30 miles north of Barðarbunga.

Less than an hour later, a 5.2 event struck Barðarbunga once more, indicating unsettled volcanic activity beneath the mountain. More than 700 earthquakes have been identified as of midnight. Tuesday saw more than 900 quakes in various swarms throughout the day and into the night, and the days prior have seen even more.

However, while this activity apparently reflects a northward migration of building magma pressure, Barðarbunga has yet to blow, and Askja appears to not be in danger of erupting.

Last Saturday, the IMO initially elevated aviation warnings for Barðarbunga to code red, suspecting an ongoing eruption beneath the Dyngjujökull glacier. However, by Monday satellite imagery and seismological measurements revealed a false alarm, and the warning system regressed to orange.

Palmi Erlendsson, a geologist at the IMO, told Reuters that the magma still has a little under 10 miles to go before even reaching the Askja caldera. If Barðarbunga begins a sub-glacial eruption before then, it might never make it. However, if it does make the trip, it is still only likely that one volcano - not both - will erupt. It would even be preferable that Askja erupts, as it's not covered in a thick sheet of ice - a flooding and heavy ash hazard.

"That would not be as dangerous," Erlendsson said, "but it's impossible to say what will happen."