Within 24 hours, lava flowing from the Holuhraun fissure will enter the one of the branches of Jokulsa a Fjollum glacial river, if the advancement rate remains the same, says volcanologist Thorvaldur Thordarson. Volcanic activity in Holuhraun has not diminished since yesterday.
"The lava field has been advancing towards the westernmost outlet of Jokulsa a Fjollum glacial river, with a rate of about 40 metres per hour," says Thordarson, who is observing the eruption in Holuhraun along with collagues from the University of Iceland´s Institute of Earth Sciences and the Icelandic Met Office.
"If the lava flow remains steady, we should see the lava entering the riverbed sometime in the afternoon tomorrow," he says. "I do not expect much explosive activity, but we should however see some violent magna/water interaction when the lava meets the glacial runoff."
The glacial river runs from the Dyngjujokull outlet glacier in several branches; the branch which the lava is heading for is one of the larger ones.
According to the most recent status report from the Civil Protection Agency´s Scientific Advisory Board, the volcanic activity in Holuhraun has remained steady. The main eruption is at the fissure which opened last Sunday; less so in the smaller fissure to the south, which started erupting early yesterday morning.
Seismic activity has decreased since yesterday, with appr. 90 earthquakes detected since midnight. As before, the strongest events are happening in the Bardarbunga caldera; at 05,40 GMT a magnitude 5 earthquake occurred in the caldera. At least 14 earthquakes of magnitudes greater than 5 have been located since 16 of August.
(Volcanologist Thorvaldur Thordarsson, at Askja, near the Holuhraun eruption)
During the interview with RUV today, Dr. Thordarson was at the newest fissure, which opened yesterday morning. "The activity there is fairly low. Lava is coming from a 100 - 150 metre long part of the fissure, with small lava fountains visible."