Cracks, 6 km long, have been seen in Dyngjujökull, northeast of Bárðarbunga, as RÚV just reported. It has also been reported that a new caldera has been formed in Bárðarbunga. Mbl.is reports that an eruption has started below the glacier, but this is not confirmed by the Icelandic Met Office.
Scientists from the Icelandic Met Office and the Institute of Earth Sciences, together with representatives of the Civil Protection Department in Iceland, met earlier today to discuss the ongoing unrest at Bárðarbunga volcano.
Their main conclusions are:
Intense seismicity continues. Almost 1,300 earthquakes have been detected in the automatic network since midnight. This activity has mostly been in the intrusive dike, which now stretches some 12 km north of the glacier's edge. A few earthquakes have also been detected near the Bárðarbunga caldera, the largest a magnitude 2.7. There were no signs of volcanic tremor.
Earthquakes are occurring mostly beyond the edge of the Dyngjujökull glacier and the intrusion itself has migrated about 1 km northwards since yesterday.
At 00:16 UTC today, a magnitude 5.3 earthquake occurred in the caldera of Bárðarbunga.
At 02:50 UTC, another similar-sized earthquake (magnitude 5.2) took place in the same region.
At 01:52 UTC a magnitude 4.5 earthquake was detected on the eastern side of the Askja volcano. This was followed by a few micro-earthquakes in the same area.
The dike intrusion beneath Dyngjujökull is thought to be about 40 km in length.
Modeling of GPS data indicates that about 20 million cubic meters of magma have been added to the volume of the intrusion in the last 24 hours.
Modeling results suggest that the dike intrusion is causing stress changes over a large area, including the region to the north of the dike's extent; this could account for the increased seismicity at Askja volcano.
There are no indications that the intensity of the activity declining.