3.1.5.3 - A recent volcanic event and responses

A fissure eruption beside Grindavík

The 14 January 2024 event occurred near Hagafell, beside Grindavík on Iceland's Reykjanes Peninsula, within a region of divergence and recurrent magma intrusion.

A dyke is a sheet-like magma intrusion that cuts through rock. Intrusion can deform the surface and reactivate faults before or during eruption; cracks and seismicity are not merely damage caused by lava already on the surface. According to the Icelandic Meteorological Office's dated updates, an intense earthquake sequence and major GPS/pressure changes showed magma movement before an eruption began at 07:57 UTC. At that early update the southern end of the fissure was about 900 m from town and on the town side of deflection barriers being constructed north of Grindavík.

At 12:10 UTC a second fissure opened just north of the town; by the 15:30 update lava had entered Grindavík. The following day's measurements described up to 1.4 m displacement in 24 hours distributed across fissures in town. This is a local deformation measurement, not the width of every crack or a national earthquake magnitude. The IMO also reported that the second fissure provided no recognisable warning signs on its monitoring equipment. Useful warning of general unrest did not identify every vent's exact location and time.

The local tectonic setting explains basaltic fissure activity, while the dyke's position explains why risk shifted close to buildings. A general map of a plate boundary alone could not locate that day's most damaging pathway.

Impacts and their different pathways

Grindavík's impacts combine direct lava and ground damage with longer disruption to housing, services and decisions about the town's future.

The official October 2024 safety leaflet records three houses destroyed by flowing lava inJanuary 2024 and significant cracks and building damage during the unrest. House destruction and deformation are primary physical impacts. They remove homes and alter the urban surface; solid lava and unstable fissures can restrict subsequent access. Potential gas exposure depends on winds and emissions; the IMO issued gas forecasts, but those forecasts do not establish observed illness or acid-rain damage in town.

Social impacts include displacement and uncertainty about safe return, alongside the direct loss of homes and belongings. Economic consequences include property losses, interrupted access and the costs of repair, inspection and relocation. Natural Catastrophe Insurance's 15 January update described assessment delays and the possible need to reinspect properties after new fissure changes. Interrupted assessment is secondary to the physical event and extends uncertainty for affected owners.

Environmental effects include lava burial of existing surfaces and continuing unstable ground, while political effects involve decisions about access, protection expenditure, compensation and permitted rebuilding. These categories overlap: whether a household can move depends partly on financial assistance and public decisions. A completed buyout later in 2024 is a response to sequence-wide disruption, not an estimate of the damage caused by three burned houses alone.

On 20 January Civil Protection reported that power appeared active throughout town, while heating remained unavailable in the harbour and eastern urban area. About 900 of approximately 1,200 residences had been inspected by plumbers. The report's next-day completion goal remains a goal. Restoring or checking one utility is evidence of partial recovery, not proof that buildings and ground were safe for normal occupation.