The activity at the eruption site, dubbed Sundhnúksgígar, continues at reduced levels.
The lava-fountaining eruption at the 3.5-km long eruptive fissure has restricted from the whole-length fountaining at the initial phase to only five eruptive vents, meaning about one-third of the fissure is currently active. Fissures have been shrinking during this time, turning into eruptive vents.
Lava fountains continue to generate molten lava clots that, in turn, have been piling lava material and building the growing spatter ramparts along the vents. In addition, hot fluid blebs fall to the ground, coalescing and thereby feeding the easterly spreading field of lava. The height of fire fountains has lowered from an initial several hundred of meters to 30 meters, although some lava jets may exceed 100 meters.
Fountaining is to be triggered by sudden release of CO2-rich bubbles trapped at reservoir roof.
The gas-steam plume with small amount of ash continues to extend towards the west and northwest and gas pollution might be remarkable in Vestmannaeyjar today. According to the weather forecast, the area in the vicinity of the capital town might be gas-affected late tonight or tomorrow morning.
A new hazard assessment map is being prepared, and it will be published later today.
Source: Icelandic Met Office volcano activity update 19 December 2023
