Bárðarbunga, Iceland: A small fissure eruption has started north of Dynjujökull

A flight over the glacier has discovered a row of 10-15 m deep cauldrons south of the Bárðarbunga caldera. They form a long line. The cauldrons have been formed as a result of melting, possibly sub-glacial eruption, uncertain when. There are three circular crevasse formations, about 5 km in total length. The ice thickness in the area is 400-600 m. No signs of flooding have been detected.

Now a small fissure eruption further north has been detected.

The Aviation Colour Code remains at the ‘orange’ level for Bárðarbunga.

Iceland Met Office reports:

A fissure eruption has started north of Dynjujökull.

29th August 2014 02:45 – An eruption north of Dyngjujökull

An eruption started in Holuhraun north of Dyngjujökull at around 00:02. Seismic tremor was observed on all seismic stations and the web camera installed in the area by Mila has showed some nice pictures of the eruption.  It is a small fissure eruption and at 02:40 AM the activity appears to have decreased.

28th August 2014 18:14 – from geoscientist on duty

Since midnight over 1100 earthquakes have been detected by the automatic system. The dyke does not appear to have migrated further north since noon. The main activity is in the dyke and at similar depth as before (8-12km). One earthquake of M5 occurred at 08:13 AM by the northern rim of the Bardarbunga caldera. Two minutes earlier (08:11) another event of M3.9 occurred at a similar location. A few earthquakes were detected near Askja, the biggest one of M2.7.

28th August 2014 12:35 – from of the Scientific Advisory Board

Scientists from the Icelandic Meteorological Office and the Institute of Earth Sciences, together with representatives of the Civil Protection in Iceland, met today to discuss the on-going unrest at the Bárðarbunga volcano.

Conclusions of the Scientific Advisory Board:

  • 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 yesterdayevening, 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 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 dyke have an effect on the Askja area.
  • Since yesterday, the length of the dyke under Dyngjujökull has increased by 1-1.5 km to the north, which is considerably less than in the last days. The dyke 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.
Iceland earthquake swarm 20140829

Iceland earthquake swarm 20140829

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