Geophysicist Páll Einarsson believes that Bárðarbunga volcano, which is currently feeding the eruption in Holuhraun, may impact other volcanoes in the vicinity, most likely Tungnafellsjökull, where increased seismic activity has been picked up.
“Almost every day now we see earthquakes in Tungnafellsjökull clearly related to these events so Bárðarbunga is trying to stir up some action in Tungnafellsjökull,” Páll commented in an interview with RÚV.
Páll explained that there is a multitude of volcanoes to the north and west of Vatnajökull which are believed to be connected in some way. Bárðarbunga lies under the northwestern glacier. Grímsvötn is another well-known sub-glacial volcano.
Other well-known volcanoes in the vicinity, in addition to the aforementioned Tungnafellsjökull the north of Vatnajökull, include Torfajökull, Hamarinn (aka Lokahryggur), Kverkfjöll and Askja.
Páll finds it unlikely that the current events will trigger an eruption in Askja, as earlier speculated, even though the northern edge of the new lava field is approaching the volcano.
“The longer that the current course of events carries on, it becomes less likely, but there are great many possible scenarios,” he said. “At the moment, [an eruption in] Tungnafellsjökull is most likely.”
Bárðarbunga is known for having an impact on other volcanoes. The so-called Settlement Eruption of 871 is believed to have been a joint effort by Bárðarbunga and Torfajökull. In the Veiðivötn and Laugahraungos eruptions from 1477, a large intrusive dike from the Bárðarbunga system started an eruption in Torfajökull.
More recently, Bárðarbunga is believed to have caused the sub-glacial eruption in Gjálp in 1996, resulting in a flood, when a dike is thought to have formed to the south from the volcano.
The eruption in Holuhraun has now carried on for four months. There has been little seismic activity in Bárðarbunga in recent days but a 5.3 magnitude earthquake hit the caldera on December 30, ruv.is reports.