Eruption on the Sundhnúkur Fissure Swarm
- An eruption began between Stóra-Skógfell and Sýlingarfell at 11:14 PM on 20 November
- The first signs of the magma intrusion were detected on instruments at around 10:30 PM.
- The length of the eruptive fissure is estimated to be approximately 3 km, with its southern end located near Sýlingarfell.
- Gas emissions are being carried southward over Grindavík.
- Link to IMO's gas pollution forecast
Updated at 02:10
The activity in the eruption appears to have peaked. The fissure seems to have stopped expanding, and based on measurements from the Icelandic Meteorological Office, there are no indications that the activity will increase.
The length of the eruption fissure is estimated to be about 3 km. The lava flow is spreading both eastward and westward. At this point, the lava front is approximately 500 meters away from Grindavíkurvegur to the west.
This eruption is significantly smaller than the last eruption, which began on 22 August. The estimated lava flow rate at present is about 1,300 m³/s, compared to approximately 2,500 m³/s during the August eruption.
What stands out is that seismic activity did not start increasing in the weeks leading up to this eruption, as was observed in previous events. The amount of magma that had accumulated beneath Svartsengi was similar to the amount prior to the last eruption. However, the recent trend indicates that increasingly larger volumes of magma are required to trigger the next event. This suggests that the pattern observed in earlier eruptions may be changing.
(Photo: Civil Protection/Björn Oddsson)
Updated at 00:10
A small earthquake swarm began at around 10:30 PM on 20 November. This was followed by pressure changes at 10:37 PM in boreholes operated by HS Orka. Both independent measurements were a clear sign of the onset of a magma intrusion.
At 11:14 PM on 20 November, a volcanic fissure opened between Stóra-Skógfell and Sýlingarfell. The fissure extended north-eastward.
Initial reports of lava-flow indicate that lava is moving westward, south of Stóra-Skógfell. No lava flow has been observed heading southwards towards Grindavík.
Strong northerly winds in the area are directing gas emissions southward over Grindavík.
Map showing the estimated location of the eruptive fissure as of 11:40 PM on 20 November. The location is based on radar data from IMO's radar station at Keflavík Airport.
