Five Magma Intrusions, Three Eruptions

svartsengi power plant reykjanes

Five magma intrusions have formed near the town of Grindavík, Southwest Iceland, since November but only three of them have broken the surface as eruptions. Magma continues to collect below Svartsengi and uplift (land rise) continues at the site. Recent earthquakes on Reykjanes are more likely a result of magma cooling underground than signs of an impending eruption, according to Salóme Jórunn Bernharðsdóttir, natural hazard specialist at the Icelandic Met Office.

Three brief eruptions occurred on the Reykjanes peninsula near the town of Grindavík in December, January, and February. In late February, as the magma chamber below Svartsengi filled once more, experts predicted a fourth eruption would occur in early March. However, while collecting magma flowed out of the chamber, it never broke the surface and now appears to be cooling underground.

Magma continues to collect below Svartsengi and the amount is now more than it was before the magma intrusion in early March. Salóme told RÚV that if another eruption occurs at the site, it will likely be preceded by the same seismic activity as the last three eruptions in the area.

The eruptions have not impacted flights or travel to and from Iceland.

Read more about the recent eruptions on the Reykjanes peninsula.

Reykjanes Could Erupt Again Next Week

Grindavík volcanic eruption January 2024

The next eruption on the Reykjanes peninsula could occur as soon as next week, RÚV reports. Land uplift at Svartsengi is occurring at a faster rate than prior to the January 2024 eruption in the area. Kristín Jónsdóttir, head of the natural hazards department at the Icelandic Met Office, says an eruption or other volcanic event could occur with little notice.

Magma chamber below Svartsengi

Land by the Svartsengi Power Plant and the Blue Lagoon has risen by up to 8 millimetres per day in recent days, slightly faster than before the January 14 eruption outside of the town of Grindavík. This indicates that the magma chamber beneath Svartsengi is likely expanding and could eventually causing an eruption or form a magma tunnel like the one that formed below the town of Grindavík at the end of last year.

Kristín believes such an event is not far off. “Assuming that this continues at a similar pace as has happened before, it can be expected that there will be another magma outburst in February, around mid-February, or even next week,” Kristín stated.

Eruption could occur with little notice

“The magma could start flowing without there being much seismic activity or us getting a lot of warning long before,” Kristín stated. She pointed out that seismic activity only increased one hour before the December eruption at Sundhnúkagígar.

Read more about the recent eruptions on the Reykjanes peninsula.

Iceland’s Reykjanes Peninsula Likely to Erupt Again Soon

svartsengi power plant reykjanes

Magma is collecting below Iceland’s Reykjanes peninsula again and experts say another eruption could happen at any time. The land by Svartsengi has now risen more than it did before last month’s eruption. The speed of uplift has also increased again, after slowing down last week.

Magma chamber refilling

Following two months of earthquakes and land deformation, Iceland’s Reykjanes peninsula experienced a short but powerful eruption from December 18 to December 21. According to Benedikt Ófeigsson, Coordinator of Deformation Observation at the Icelandic Met Office, the magma chamber beneath Svartsengi has now replenished 75% of the magma expelled by the December eruption.

These developments indicate that another eruption is on the way, Benedikt told RÚV.  The most likely location is the Sundhnúkur Crater Row, between Stóra-Skógfell and Hagafell mountains. According to Benedikt, the eruption could begin there “at any time.”

Blue Lagoon remains open

An overnight evacuation order remains in effect for the nearby town of Grindavík (pop. 3,600). The town was evacuated on November 10 due to powerful earthquakes that damaged roads, homes, and infrastructure in and around the community.

The nearby Blue Lagoon was reopened to visitors on Saturday. Benedikt says an eruption is not likely to occur in the area around the lagoon. “So even if an eruption begins, there will most likely be plenty of time to evacuate people.”

The Reykjanes peninsula, the location of Keflavík International Airport and a stone’s throw from Iceland’s capital, Reykjavík, has entered a period of increased volcanic activity that could last hundreds of years. The four eruptions that have occurred on the peninsula since 2021 have not impacted infrastructure or flights. The earthquakes and deformation preceding the December 2023 eruption, which caused damage in and around Grindavík.

Suspend Blue Lagoon Transport Due to Threat of Eruption

Reykjanes Svartsengi power plant

Reykjavík Excursions has suspended all transport services to the Blue Lagoon due to the risk of an eruption near the site. The Blue Lagoon itself remains open to visitors, a decision Suðurnes Police Commissioner Úlfar Lúðvíksson called “irresponsible” in a RÚV interview yesterday evening. Magma is collecting some 4-5 km below the surface of the Reykjanes peninsula just west of the Blue Lagoon and Þorbjörn mountain, but so far there have been no signs of volcanic unrest.

Infrastructure and town threatened

The Reykjanes peninsula has seen three eruptions in the past three years, indicating the start of a period of volcanic activity that could last centuries. All three eruptions were preceded by earthquakes and land rise similar to the ongoing activity near the Blue Lagoon. However, land rise and earthquakes have also occurred on Reykjanes during this period without leading to an eruption.

While the previous three eruptions did not impact infrastructure or inhabited areas, the midpoint of the current activity is not only near the Blue Lagoon, it also threatens the Svartsengi Power Station and the town of Grindavík. Not only is the location closer to infrastructure, but experts have also indicated that a potential eruption from the magma intrusion could produce faster-flowing lava than the three recent eruptions on Reykjanes. This would mean inhabitants and visitors to the area would have limited time to evacuate.

Evacuation plans have been issued for the town of Grindavík and are available in English, Polish, and Icelandic.

Prioritising staff and customer safety

“Like everyone, we are trying to figure out what the scientists are saying and what the pace [of the seismic activity] is,” Reykjavík Excursions CEO Björn Ragnarsson told Vísir yesterday when asked about the decision to suspend transport to the Blue Lagoon. “We put a lot into the safety of our staff and customers and decided based on our interests as a company to make this decision today.”

On Reykjavík Excursions’ website, it is not possible to book a Blue Lagoon transfer for the coming days, though it is possible to book from November 19. The company has a notice about the seismic unrest on their Facebook page as well where they note they have suspended trips to the Blue Lagoon from noon today. The website also features a banner warning of potential volcanic unrest on Reykjanes asking customers to subscribe to SafeTravel to receive alerts.

Five volcanic systems on Reykjanes

Iceland is located on a rift between two tectonic plates, the North American and the Eurasian. Broadly speaking, the rift cuts through Iceland diagonally from the southwest to the northeast and the movement of the plates is what causes Iceland’s volcanic and seismic activity. The rift cuts across the Reykjanes peninsula, which contains five separate volcanic systems. The magma now collecting below the surface is within the Eldvörp-Svartsengi system.

The Reykjanes peninsula alternates between periods of seismic activity lasting 600-800 years and periods of volcanic activity lasting 400-500 years. The recent eruptions indicate the start of a period of volcanic activity on Reykjanes.

Read more about the geology of the Reykjanes peninsula.

New Magma Intrusion Below Reykjanes Peninsula

Þorbjörn efitr Pálmi Erlendsson Veðurstofan

Magma is collecting some 4 km [2.5 mi] below the surface of the Reykjanes peninsula, not far from where three eruptions have occurred over the last three years. The new magma intrusion is just northwest of the town of Grindavík, close to Þorbjörn mountain and the Blue Lagoon. While there are no signs that an eruption is imminent, a specialist at the Icelandic Met Office says it is a possibility both by Þorbjörn Mountain as well as by Fagradalsfjall, the area where the last three eruptions on Reykjanes occurred.

Earthquakes and uplift (land rise) have occurred before all three recent eruptions on the Reykjanes peninsula, the most recent eruption occurring just last summer. On October 24, an earthquake swarm began northwest of Grindavík, where uplift of 3 cm is now being detected. Strong earthquakes have continued at the site, with an earthquake above M4 felt across the capital area at noon yesterday.

Although experts now say magma is collecting below the site, it will not necessarily lead to an eruption. Benedikt Ófeigsson, a coordinator at the Icelandic Met Office, says an eruption could also still occur at Fagradalsfjall. “We cannot write off Fagradalsfjall immediately,” Benedikt told RÚV. “We are still seeing deformation (uplift) there and it could just as well be that the next eruption will occur there, but we are monitoring both places now.”

While there are no indications that an eruption is imminent, the Department of Civil Protection and Emergency Management has declared an uncertainty phase on the Reykjanes peninsula. Experts have stated that the recent eruptions on Reykjanes indicate the start of a period of volcanic activity that could last decades or centuries. None of the three recent eruptions have impacted inhabited areas or infrastructure.

Shallower Quakes, Seismic Activity Similar to 2022 Eruption

Meradalir

New data shows that magma has accumulated at less than one kilometre below the surface in the area between the mountains Keilir and Fagradalsfjall on the Reykjanes peninsula. The flow of magma has been deemed “considerable.” These are strong signs that an eruption may be imminent, a natural hazards expert with the Icelandic MET Office told RÚV this morning.

Following a similar pattern to the previous eruption

The seismic activity in the area between the mountains Keilir and Fagradalsfjall on the Reykjanes peninsula continues to decrease. Lovísa Mjöll Guðmundsdóttir, a natural hazards expert at the Icelandic MET Office, told RÚV this morning that the activity was “very similar to the previous eruption last year.”

“The seismic activity continues to diminish, and the magma has accumulated at a depth of one kilometre. If the magma reaches the surface, we can expect it to happen in the next hours or days. We’re on our toes and monitoring all the available data carefully.”

Lovísa observed that the experts of the MET Office – who monitor data in real-time – had not detected further deformation in the landscape. The tremors continue to grow more shallow, despite the reduction in seismic activity.

“Yes, the earthquakes are growing more shallow. This is very similar to last year’s eruption when activity decreased in this manner. The earthquakes were occurring at a similar depth. So we may as well expect that this could happen in the near future.”

“And if an eruption were to happen, it would happen without much notice?” a reporter with RÚV inquired. “Yes, very little notice,” Lovísa replied. “So we’re continuing to monitor events closely to try to determine the location of the eruption.”

As noted by RÚV, about 6,500 earthquakes have been recorded since the earthquake swarm began on the Reykjanes Peninsula on Tuesday, with the largest earthquake measuring 4.8 in magnitude. The Department of Civil Protection and Emergency Management has declared an uncertainty level. The flight colour code over Fagradalsfjall remains orange. Travellers are advised against visiting the area.

Readers can monitor activity near Fagradalsfjall via webcams here.

Magma Likely Collecting Under Reykjanes Again

Increasing uplift (land rise) has been measured on the Reykjanes peninsula since the beginning of April, a sign that magma is collecting below the surface. There are no indications that an eruption is imminent, however. The peninsula has been the site of Iceland’s two most recent eruptions, in 2021 and 2022.

Magma far below the surface

Land on the Reykjanes peninsula has risen between 2 and 2.5 centimetres (around one inch) since the beginning of April, Hildur María Friðriksdóttir, a natural hazard specialist at the Icelandic Met Office told RÚV. “What we’ve been seeing now is steady uplift by Fagradalsfjall [the site of the 2021 and 2022 eruptions]. We aren’t seeing any recent changes or anything sudden. We are seeing uplift which is probably due to magma that is collecting again beneath the site. It’s at a significant depth. The situation is stable at the moment.”

First eruptions in nearly 800 years

An eruption began on the Reykjanes peninsula on March 19, 2021, the first in the area for nearly 800 years. It lasted around six months, until September 2021. It was followed by another, though shorter, eruption at the same location in 2022, lasting just over two weeks. Experts have stated that these eruptions likely mark the beginning of a more active volcanic period on the peninsula.

Familiar activity, but no indications eruption is imminent

Both the 2021 eruption and 2022 eruption were preceded by uplift as well as strong earthquakes felt across Southwest Iceland and the capital region. An M 3.2 earthquake occurred on the Reykjanes peninsula, by Kleifarvatn lake, on June 28. Hildur says, however, that earthquake activity has been fairly stable on Reykjanes recently and it is difficult to say whether there will be another eruption on the peninsula, or when. “There is nothing currently that indicates an [imminent] eruption. I don’t dare to promise anything but there’s nothing that indicates an eruption as it stands.”

Read more about the geology of the Reykjanes peninsula.

M4.9 Earthquake in Bárðarbunga Caldera Caused by Magma Intrusion

A lake on top of Bárðarbunga on Vatnajökull glacier.

A strong earthquake occurred this morning in Bárðarbungacaldera located on the Vatnajökull glacier. The earthquake measured M4.9 and was felt as far away as Akureyri. Kristín Jónsdóttir, head of the Icelandic Met Office’s Volcanoes, Earthquakes, and Deformation Department, told RÚV the earthquake was caused by a magma intrusion, but there are no indications the magma is on its way up to the surface.

Land rise has been occurring at Bárðarbunga since the end of the Holuhraun eruption in 2015. Kristín says there are no indications the current activity is related to the land rise and melting ice currently occurring at Askja volcano.

There are also no indications an eruption from Bárðarbunga is imminent, Kristín says. “Bárðarbunga could be in this phase, this magma accumulation phase, and then we get these strong quakes at certain intervals, for decades.”

Land Rises Four Centimetres on Reykjanes

Grindavík - Þorbjörn

The land around Svartsengi, on the Reykjanes peninsula, has risen 4 centimetres since April 21. The uplift is most likely due to a magma intrusion 4-5km below the surface. Satellite images published by the Icelandic Met Office indicate the intrusion is 7-8km long and stretches west of Þorbjörn mountain and underneath Svartsengi Power Station. An earthquake swarm is ongoing at the site, but there is no sign of volcanic unrest.

These geological events are reminiscent of landrise that occurred in the area in 2020. While in that instance, the magma that was collecting underground never reached the surface, a volcanic eruption did occur nearby on the peninsula in 2021, at Fagradalsfjall. While the 2021 eruption was far from infrastructure, the growing magma intrusion is located underneath a geothermal power plant, which is at risk of damage if magma reaches the surface.

Residents of the nearby town of Grindavík were invited to a town hall meeting yesterday evening to discuss the geological activity and go over preparedness in the case of an eruption. Travellers and hikers on the Reykjanes peninsula are warned to stay away from steep inclines, where earthquakes can cause landslides or rockfall. The Civil Protection Department website features earthquake preparedness information in English.

Experts have stated that it is too early to say whether the activity will result in an eruption.

The Department of Civil Protection and Emergency Management has declared an uncertainty phase in the area and the aviation code for the area has been changed to yellow.

Magma No Longer Accumulating By Þorbjörn Mountain

Grindavík - Þorbjörn

Magma has stopped collecting under Þorbjörn mountain on the Reykjanes peninsula, and the uplift (land rise) that it was causing has now stopped. The Icelandic Met Office reports that seismic activity in the area has decreased significantly, though it remains important for the area’s residents to take preventative measures due to the likelihood of earthquakes.

In late January, Icelandic authorities declared a state of uncertainty due to possible magma accumulation a few kilometres west of Þorbjörn mountain. Land rise and earthquake swarms were detected in the area, suggesting magma was accumulating underground. Nearby residents were prepared for a possible eruption, though authorities stated it was more likely the activity would calm without one, as has been the case.

“In the beginning of April the uplift in Þorbjörn decreased and, in the second part of the month, it stopped. The area around Þorbjörn is now most likely recovering after the large induced stress, and the injected magma is cooling down and contracting,” a notice from the Icelandic Met Office states.

Earthquakes may still occur

“The current observations and the course of events over the last several months suggest that there is an active long-term process ongoing in the area,” the notice continues. “The possibility of renewed activity in the near future at Þorbjörn, Reykjanes or elsewhere on the Reykjanes peninsula cannot be discarded.”

The Met Office encourages residents of the area to prevent damage or injuries by securing furniture in their homes so that they do not fall in the event of an earthquake. This includes residents in the Reykjavík capital area, as earthquakes on the Reykjanes peninsula can be felt there as well.