Holuhraun eruption from the plane
It is Wednesday morning. I arrive at my office at the University of Iceland after the International Carbon Conference in Reykjavík and quick visit to Oslo. In the hallway I am already going over my to do list in my mind. The first person I meet is Nicole, calling: “We are flying to the eruption! Andri and Siggi booked the plane!” Everyone in the geochemistry team is extremely excited. Everyone is heading home to get their camera. Everyone is charging the camera batteries. Everyone who doesn’t have camera is borrowing a camera.
Finally, we meet at the airport. After approximately 40 minutes of flying from Reykjavík we reach the eruption site. For those who do not know, (is there anyone who doesn`t know?!) there is an ongoing fissure eruption is taking place in Iceland, in the Holuhraun area, situated north of the Vatnajökull glacier. After an intensive series of seismic events the eruption started on 29th Friday of August and, apart from a few small interruptions, continues to erupt.
The first impression from the plane was absolutely incredible. I have never seen anything so intensely orange in my life! For next half hour we flew around the eruption enjoying the beauty of nature while trying desperately to capture the best moments through the airplane’s tiny windows. As we were flying around scientists on the ground have been working continuously in a closed area with permission from Civil Protection. They follow strict safety guidelines to protect themselves against the dangers of toxic gas and the possibility of jökulhlaup (glacial outburst flood) if an eruption starts under the glacier. We therefore took images of the surrounding glacier Dyngjökull (part of Vatnajökull) too. The floods can be potential hazard for animals due to the increased fluorine concentrations from the eruption.
In this kind of event, scientists from the Icelandic Meteorological Office and the Institute of Earth Sciences, and representatives of the Civil Protection in Iceland attend meetings of the Scientific Advisory Board of the Icelandic Civil Protection. Their Latest conclusions from Thursday are as follows:
- The intensity of the ongoing eruption in Holuhraun is not declining. Lava is flowing toward ENE and it has been elongated considerably since yesterday. Since this morning, a preliminary estimate of lava field extension is about 10.8 km2.
- Seismic activity is still detected in the northern part of the dyke intrusion, along the eruption site and extending south below Dyngjujökull. Event rates are lower than in recent days, 180 earthquakes have been detected since midnight until noon. Four events larger than M4 have been detected in Bárðarbunga caldera. The largest one (M4.8) occurred last night at 03:09.
- The low frequency tremor seen yesterday disappeared last night but started again this morning, however minor compared to yesterday. The source of the tremor is not certain however possible explanation could be magma-water interaction although this interpretation has currently not been confirmed by other observations.
- There are no signs of a subglacial eruption under Dyngjujökull. No obvious changes such as increased water flow or cauldrons on the glacier surface were observed from scientists on board TF-SIF yesterday. Water meters in Jökulsá á Fjöllum do not show any unusual changes in discharge and electric conductivity.
- The GPS time series indicate slower rate of deformation in the last 24 hours. The current deformation pattern north of Vatnajökull still suggests volume increase in the dyke. No significant signs of deformation are observed around Bárðarbunga.
- There have been no observations of ash-fall away from the eruption site. Ash production is negligible.
Sulphur dioxide emission continues. Low-wind speed condition is present in the area at the moment. Based on radar images the eruption cloud from today (composed of steam and volcanic gases) has not drifted far away and is mostly concentrated around the eruption site. Stations measuring SO2 further away from the eruption site are showing concentration below health and safety thresholds. Since this morning, the cloud reaches 6 km of altitude. The volcanic cloud will drift towards south in the coming hours due to wind rotation.
Four scenarios are likely:
- The migration of magma could stop, resulting in a gradual reduction in seismic activity and no further eruptions.
- 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.
- 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.
- 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.
Other scenarios cannot be excluded.
For more information head to