Bardarbunga volcano update: Eruption continues, status update
The fissure eruption on Holuhraun continues with no signs of weakening. Icelandic press now counts as a relatively large effusive eruption, comparable to the Krafla fissure eruptions in 1980-1984.
Mo, 1. Sep 2014, 17:3817:38 PM | VON: T
The active eruption fissure is now around 2 km long and has erupted an estimated 16-25 million cubic meters of lava, covering approx. 3-5 square kilometers.
Lava flows continue to expand northwards from the vents. The lava effusion rate was re-estimated to 300-500 cubic meters / second for 20:00 h yesterday evening.
It is unclear how the situation will evolve, in particular because intense earthquake and deformation activity continue, suggesting that magma continues to intrude into fissures at depth, a process that could significantly modify the ongoing eruption at any time.
From the latest IMO report:
"In connection with the FUTUREVOLC project, a gas monitoring station has been set-up near to the eruption site. Gas measurements indicate a high level of sulphur dioxide. People could be exposed to highly dangerous gas levels close to the eruption. It is essential that those visiting the eruption site are equipped with gas sensors and gas masks.
"- According to the latest GPS observations, horizontal ground movements continue in response to the dyke intrusion. There is no clear sign of a pressure decrease in the dyke intrusion in connection with the ongoing eruption, although there are irregularities in GPS displacements at nearby stations. The northern extent of the dyke intrusion has not changed to any great extent.
"- When Sunday's eruption began earthquake activity decreased somewhat, although seismicity remains high, with over 500 earthquakes detected since midnight today. Most of the seismicity is occurring on the northern end of the dyke intrusion, covering a 15-km-long region that extends partly beneath Dyngjujökull and north of the ice margin.
"- At 08:58 UTC today, a magnitude 5.0 earthquake was recorded on the Bárðarbunga caldera, and another of magnitude 5.2 at 11:41 UTC in the same region.
"It remains unclear how the situation will develop. Four scenarios are still considered most likely:
1 The migration of magma could stop, resulting in a gradual reduction in seismic activity and no further eruptions.
2 The dike could reach the Earth's surface causing another eruption, possibly on a new fissure. Lava flow and (or) explosive activity cannot be excluded.
3 The intrusion reaches the surface and another eruption occurs where either the fissure is partly or entirely beneath Dyngjujökull. This would most likely produce a flood in Jökulsá á Fjöllum and perhaps explosive, ash-producing activity.
4 An eruption in Bárðarbunga. The eruption could cause an outburst flood and possibly an explosive, ash-producing activity. In the event of a subglacial eruption, it is most likely that flooding would affect Jökulsá á Fjöllum. However it is not possible to exclude the following flood paths: Skjálfandafljót, Kaldakvísl, Skaftá and Grímsvötn.
5 Other scenarios cannot be excluded." (IMO)
Mo, 1. Sep 2014, 07:57
The fissure eruption is continuing at a stable level with little variation. A curtain of lava fountains up to 70 m high is being erupted above the fissure and pahoehohoe type lava flows are expanding to several kilometers around it, forming a growing flat lava flow field. ... Read all