Sundhnúkagígar eruptions Reykjanes

Sundhnúkagígar eruptions Reykjanes

Since December 2023, six short but intense eruptions have happened in the Svartsengi volcanic system on the Reykjanes Peninsula just north of Grindavík. Sadly, these are not harmless eruptions in an isolated valley like the ones at Fagradalsfjall in 2021, 2022 and 2023. On this page you can find the latest updates and an overview of the Sundhnúkagígar eruptions in 2024, with useful links for information direct from Iceland.

2024 Grindavík state of emergency and eruptions

Update September 2024: The sixth eruption started on 22 August at at the Sundhnúkagígar crater row and has finished on 5 September. The area around Grindavík and the Sundhnúkagígar eruption site remains closed. Volcanic unrest and land uplift continues in the Svartsengi area north of Grindavík. This could lead to yet another eruption or dike intrusion in the coming months. Veður (the Icelandic Met Office) gives frequent updates on the current situation.

This map below shows the Sundhnúkagígar lava fields from December 2023 to September 2024 and the current danger zone (updated on 10 September 2024).

Volcanic danger zone around Grindavík.
Volcanic danger zone around Grindavík as per 10 September 2024. Source: Icelandic Met Office. For current road conditions and closures on Reykjanes Peninsula, see Umferdin.is.

Sundhnúkagígar eruptions Reykjanes.
The Sundhnúkagígar eruption near Grindavík on 16 March 2024. Photo: Almannavarnir.

Lava barriers to protect against future eruptions

Weeks of intense earthquake swarms and land uplift preceeded the first eruption. On 10 November 2023 a 15-kilometre long magma tunnel formed beneath the Grindavík area, and the entire town was evacuated. It remains uncertain if and when residents can return.

After the earthquakes and subsequent evacuation in November 2023, the Icelandic authorities didn’t waste time to build a lava barrier around the Svartsengi geothermal power plant and the Blue Lagoon. Another lava defense barrier has been cranked up around Grindavík. It withstood its baptism by fire on 14 January 2024 and proved to be very effective in diverting the lava flow from the main fissure, even though the barrier was only half-finished at the time.

Almost the entire town is now surrounded by the defense barriers, as well as lava flows from the last eruptions…

Sunset at the Svartsengi lava barriers, Reykjanes Peninsula, Iceland.
Sunset at the Svartsengi lava barriers near the Blue Lagoon.

Webcam screenprint of the Sundhnúkagígar eruption Sýlingarfell on 29 May 2024, Reykjanes Peninsula, Iceland.
The eruption at Sýlingarfell on 29 May 2024. Screenprint: MBL livestream.

Svartsengi-Sundhnúkagígar eruptions

Below is an overview of the Sundhnúkagígar eruptions on the Reykjanes Peninsula in 2023 and 2024. The volcanic activity concentrates around three large hills east of Grindavíkurvegur (Road 43) in the Svartsengi volcanic area. From south to north: Hagafell, Sýlingarfell and Stóra-Skógfell. Þorbjörn (Thorbjörn) is Grindavík’s signature mountain north of town and west of Road 43.

Days of activity include the first and the last day of the eruption. Initial lava flow is the maximum output during the first few hours. The interval is counted from the last day of the previous eruption to the first day of the new one.

Sundhnúkagígar eruption

🌋 18 December 2023: Eruption #1 kicked off at the Sundhnúkagígar craters, about 2,5 kilometres northeast of Grindavík. It cracked open a 4-kilometre long fissure between Sýlingarfell and Stóra-Skógfell, but the activity quickly reduced after the first day. Most of the lava flowed to the northeast, away from Grindavík.

Start: Monday 18 December 2023 at 22:17 hrs
End: Thursday 21 December 2023.
Days of activity: 4.
Initial lava flow: 200 m3/sec.
Fissure length: 4 km.
Lava field: 3,7 km2.
Interval: 38 days after the dike intrusion on 10 November 2023.

Hagafell eruption

🌋 14 January 2024: Eruption #2 was smaller, but way more destructive. It started near Hagafell and ripped right through one of the lava defence barriers north of Grindavík. The lava flow also cut off the main road into town (Road 43). Three houses were destroyed when a second small fissure erupted on the northern edge of Grindavík.

Start: Sunday 14 January 2024 at 07:57 hrs.
End: Tuesday 16 January 2024.
Days of activity: 3.
Initial lava flow: 100- 200 m3/sec.
Fissure length: 1 km, plus an additional 150-metre fissure.
Lava field: 0,7 km2.
Interval: 24 days.

Sýlingarfell eruptions

🌋 8 February 2024: Eruption #3 appeared again at the Sundhnúkagígar craters between Sýlingarfell and Stóra-Skógfell. Another lava flow went over Road 43, right at the turnoff to the Blue Lagoon. It also took out one of the hot water pipelines from the Svartsengi power plant – a rather inconvenient timing, as temperatures dropped below -10C. This eruption finished within 24 hours, making it the shortest eruption in Icelandic history.

Start: Thursday 8 February 2024 at 06:02 hrs.
End: Friday 9 February 2024.
Days of activity: 2 (but finishing within 24 hrs).
Initial lava flow: 600 m3/sec.
Fissure length: 3 km.
Lava field: 4 km2.
Interval: 23 days.

🌋 16 March 2024: Eruption #4 began at the same location. The lava flow connected the two separate lava fields and advanced to just 200 metres from Road 427 (Suðurstrandarvegur), the main road on the south coast of Reykjanes. This eruption lasted much longer than the previous three and kept going for nearly 8 weeks.

Start: Saturday 16 March 2024 at 20:23 hrs.
End: Thursday 9 May 2024.
Days of activity: 55.
Initial lava flow: 1100- 1200 m3/sec.
Fissure length: 3 km.
Lava field: 6,2 km2.
Interval: 36 days.

🌋 29 May 2024: Eruption #5 was more powerful than the ones before. It ripped open a complex series of fissures between Hagafell and Stóra-Skógfell. Huge volumes of lava rapidly flowed all the way south along the lava barriers, crashing into the base of Mount Þorbjörn and blocking two of the three roads to Grindavík. Only Suðurstrandarvegur hasn’t been overflowed. The eruption also triggered some phreatomagmatic explosions, when lava flowed into a crack in Hagafell and came in contact with ground water.

Start: Wednesday 29 May 2024 at 12:46 hrs.
End: Saturday 22 June 2024.
Days of activity: 25.
Initial lava flow: 1500- 2000 m3/sec.
Fissure length: 3,4 km.
Lava field: 9,3 km2.
Interval: 20 days.

Stóra-Skógfell eruption

🌋 22 August 2024: Eruption #6 was the most northerly and the biggest one up to now. It started along the same 4-kilometre fissure as the December 2023 eruption. A second fissure opened up further north outside the lava field near Stóra-Skógfell and took over all the activity. Most of the lava flowed to the north as well, which is a relief for Grindavík. Meanwhile, Stóra-Skógfell has become an ‘óbrynnishólmi’, an isolated hill completely surrounded by lava flows.

Start: Thursday 22 August 2024 at 21:25 hrs.
End: Thursday 5 September 2024.
Days of activity: 15.
Initial lava flow: 1500- 2000 m3/sec.
Fissure length: 7 km (😳!) – including the northern fissure that took over.
The fissure was not erupting all at the same time across its entire 7-kilometre length.
Lava field: About 15,1 km2 in total so far.
Interval: 61 days.

Webcam screenprint of the phreatomagmatic eruption at Hagafell on 29 May 2024, Reykjanes Peninsula, Iceland.
Phreatomagmatic explosions at Hagafell on 29 May 2024. Screenprint: MBL livestream.

Óbrynnishólmi – The unburnt hill

When an area in the landscape is surrounded by lava but remains unburnt itself, it is called an óbrynnishólmi, an isolated ‘hill island’ in a sea of lava. Fagradalsfjall also created some óbrynnishólmis in 2021. The first one to go was the ‘helicopter hill’ (now completely buried beneath the lava). Then followed Gónhóll, the spectacular viewing hill right in front of the crater. Not long after, the next hill behind Gónhóll was cut off when lava flows tumbled down into Nátthagi Valley (June 2021). Littli-Hrútur also made an óbrynnishólmi of the little elongated hill beneath Kistufell in 2023.

In other volcanic countries they have a name for this phenomenon too. It’s called kipuka in Hawaii and dagala in Italy (Sicily, Stromboli, Aeolian Islands).

Fagradalsfjall crater and óbrynnishólmi, Reykjanes, Iceland.
Fagradalsfjall crater and the óbrynnishólmi of Gónhóll, June 2021.

Is Reykjanes safe to visit?

The volcanic and seismic unrest is concentrated around Grindavík. This area is currently off-limits. The rest of Reykjanes Peninsula is still accessible and safe to visit. The Fagradalsfjall hiking tracks are usually open again after the first few days of a new eruption at Sundhnúkagígar, if the conditions at Fagradalsfjall are safe.

Flights to Iceland are not affected by eruptions on Reykjanes, as these type of eruptions don’t produce ash clouds. The only exception would be if an eruption happens in the sea.

Kleifarvatn lake and Krýsuvík, Reykjanes GeoPark, Iceland.
Kleifarvatn lake and the Krýsuvík geothermal area.

Useful links for updates on the Reykjanes eruptions

  • Icelandic Met Office – Detailed information about the volcanic unrest, with regular hazard maps, inflation graphs, lava flow maps and explanation of earthquake activity.
  • Visit Reykjanes – Regional page with news and information about the eruptions.
  • Safe Travel – Updates from the Icelandic Search and Rescue team (ICE-SAR).
  • Roads & Traffic – Information about road closures on the Reykjanes Peninsula.

Icelandic news sites in English

Lava field map

This interactive map with aerial photographs shows the lava fields in the region. In the section ‘Jarðeldar í Grindavík’ you can see more details, such as the lava barriers and the eruption fissures. Note: the new lava field from August 2024 is not yet visible on this map.

This is the latest lava field map from the Icelandic Met Office:

Sundhnúkagígar lava field map.
Sundhnúkagígar lava field map as per 25 August 2024. Source: Icelandic Met Office.

Scientific information

If you’re a volcano geek like me, you can read in-depth information about the tectonic rifting event and eruptions on the Reykjanes Peninsula in these research articles.

Other articles

Accessible background articles about the volcanic unrest and the impact on Grindavík.

YouTube

Geology professor Shawn Willsey has regular updates on his YouTube channel, with clear explanations about earthquakes, land uplift and other background information about the volcanic unrest on the Reykjanes Peninsula.

@ If you have any questions, let me know in the comment section below. Your questions, comments and suggestions are also helpful for other readers and travellers. Thank you for sharing.

The saddest roadsign in Iceland... Road 43 towards Grindavík on the Reykjanes Peninsula, Iceland.
The saddest roadsign in Iceland… Road 43 towards Grindavík.


© All photos and content on this website are my own, and subject to copyright (unless credited otherwise). Please contact me if you want to use a photo or quote a text from one of my articles. You’re welcome to share a link to my blog articles and photos on social media, with a tag and mention to Wilderness Coffee & Natural High.


Last update: 16 September 2024

Ask a question, leave a comment or share your thoughts 💜