The Iceland Met Office reports that since midnight, over 1,100 earthquakes have been detected by sensors on and near Vatnajökull glacier. The dike does not appear to have migrated further north since noon. The main activity is in the dike and at similar depth as before (8-12 km).
One earthquake of magnitude 5.0 occurred at 08:13 am by the northern rim of the Bárðarbunga caldera. Two minutes earlier (08:11 am) another earthquake of magnitude 3.9 occurred at a similar location. A few earthquakes were detected near Askja, the biggest one of magnitude 2.7.
Scientists from the Icelandic Meteorological Office and the Institute of Earth Sciences, together with representatives of the Civil Protection Department in Iceland, met today to discuss the ongoing unrest at the Bárðarbunga volcano. These are their conclusions:
This morning, there was a flight over the Bárðarbunga area and the surface of the glacier was surveyed. No changes to the ice crevasses southeast of Bárðarbunga, that were seen yesterday evening, were observed. These crevasses were likely formed due to melting at the ice bottom.
The depressions have been located southeast of the Bárðarbunga caldera, in all likelihood within the water divide of the river Jökulsá á Fjöllum. There are three circular crevasse formations, about 5 km in total length. The ice thickness in the area is 400-600 m.
The water level in Grímsvötn Lake has been surveyed and has likely risen by about 5-10 m in the last days, which corresponds to an addition of 10-30 million m³ of water in the lake. A slight increase in conductivity in Köldukvísl River was measured this morning, but the cause is yet unknown. No change has been measured in the Hágöngulón lagoon, Jökulsá River and Skjálfandi River. It is assumed, that the water from the cauldron has flowed into the Grímsvötn Lake or the river Jökulsá á Fjöllum.
The seismic activity is similar to that of the last days. Around midnight, three earthquakes of magnitude around 4 were recorded and one of magnitude 5.0 at 08:13 this morning, all located within the Bárðarbunga caldera.
Shortly before 08:00 this morning, there was a slight increase in seismic activity in the Askja volcano. Changes in the stress field due to expansion caused by the dike have an effect on the Askja area.
Since yesterday, the length of the dike under Dyngjujökull has increased by 1-1.5 km to the north, which is considerably less than in the last days. The dike has now reached the fissure system of the Askja volcano and GPS measurements indicate that the area there is greatly affected.
The conclusions from the meeting of the Scientific Advisory Board of the Icelandic Civil Protection will continue to be published at around noon, after the meeting, if necessary.
From the Icelandic Met Office:
The Aviation Color Code remains at the ‘orange' level for Bárðarbunga.