Unrest in Iceland As Reykjanes Enters New Era

 REYJANES - ICELAND

The recent unrest at Iceland's Reykjanes Peninsula has generated a lot of media attention, not to mention increasing the stress levels of those unfortunate enough to be on the receiving end of the unrest in Grindavik. Grindavik was evacuated following the events of November 10th, 2023, where a series of extremely strong quakes coupled with a rifting and dike emplacement event left the town with large fissure cracks running in a NE/SW direction, damaging roads, infrastructure, water and power services. Many apartments and homes are now uninhabitable and will need to be rebuilt.

The fissure/rift is estimated to be some 15km/9mi long, and several meters wide. 

This was initially thought to be the beginnings of an imminent eruption, however that has not come to pass. Instead, the fissure magma supply appears to have slowed or been cut off, which will likely result in solidification of the dike, at least pertially.

Inflation at the Svartsgeni Power Plant area, which was responsible for the current series of events after accumulated magma found its way into the current dike, now continues at an accelerated pace. Magma intrusion below Svartsgeni is espimated to contribute to an averge land rise of 1 cm per day. At this rate, it is only a matter of time until the inflation reaches the level of the Nov 10th event. 

If the inflation does reach this

it is probable that if the status quo continues, and eruption may present to the West of the Svartsgeni power plant, or perhaps migrate further to the East into the previously formed dike. It is impossible to know at this time. 

The Reykjanes peninsula (of which the Icelandic capital of Reykjavik is situated on the NE portion), is now entering into an assumed 'Volcanic Dynasty' which may last several hundred years, according to experts. The last cycle of volcanism on the peninsula ended around 1200 AD, after the settlement of Iceland (some eruptions are reported in ancient Icelandic historical sagas/records) after a long period of unrest. 

Volcanologists appear certain that this occurs in regular phases on the peninsula, driven by the rifting between the North American plate, and the Eurasian plate. The two plates are moving away from each other at around the rate that human fingernails grow per year. This eventually results in the creation of cracks through which the mantle plume under Iceland can inject magma to fill the gaps. This is what is thought to be occurring now underneath the peninsula.

If the current sequence of events does result in an eruption, it will likely happen near the end of December or the first couple weeks of January. However this is not a certainty as volcanoes don't always behave how we expect them to, there are simply too many variables.

In the event that a major or minor eruption does happen around the Svartsgeni power plant, or the nearby town of Grindavik, this will plunge the peninsula and the capitol into a new era of turbulence for the island nation. Residents that may be forced to locate will need to go *somewhere* and permanent solutions for housing will likely be needed - similar to the recent destruction in Hawaii's 2018 eruptions, and the 2023 loss of Lahaina, Maui, to fires (not volcano related).   

In Hawaii, it has been several months since the Lahaina disaster, and a little over 5 years since the Kilauea East Rift Zone eruption that resulted in the loss of over 700 homes, displacing thousands of residents. 

Iceland's situation is being closely monitored. 

Mauna Loa Erupts - Eruption Now Waning

 HAWAII

Mauna Loa, dormant since its last eruption in 1984, and after a very long inflation period with starts, stops, and starts, entered into an eruptive phase Nov 30th (HST) with a visually spectacular eruption. The eruption began with a fissure eruption at the summit of Moku'āweoweo caldera at just around midnight.

Animated 24-hour GIF of the start of the eruption via USGS/HVO

This part of the eruption effused a very large amount of lava in a short period of time, but quickly ended after overfilling the SW caldera rim.

Shortly after, fissures on the Northwest Rift Zone (NWRZ) erupted. A total of four fissures erupted with the dominant fissure being the third and most effusive. The main lava flow threatened the Daniel K. Inouye highway (or, Saddle Rd) on the Big Island, but has since stalled at about 1.7 miles away from the highway, one of the critical roads for the Big Island which enables the far-away communities to reach each other.

Lava flow map of Mauna Loa's recent eruption as of 12/9/22

Mauna Loa has not been actively erupting for around 38 years, which is the longest dormant period since recordkeeping began. The inflationary period began sometime in 2011 and has continued on and off since then. 

The eruption has unfortunately cut off a critical road to one of the world's premier CO2 monitoring sites operated by NOAA, which is responsible for measuring CO2 PPM measurements which are a critical gauge in measuring the effects of climate change and global warming. Access to this site is currently cut off due to lava crossing Mauna Loa Observatory Road early in the eruption.

A live stream of the eruption is available via HVO/USGS at Mauna Loa Eruption, HI - USGS live stream - YouTube, however the camera does go in and out of service due to extreme weather and wind conditions. 

Image of the now waning eruptive fissure, fissure3 as of 4:30pm HST 12/9/2022

 As of today, the eruption seems to be waning, however magmatic tremor remains present. It is possible the eruption pauses and resumes, is done entirely, or that new eruptive fissures can form as long as volcanic tremor remains present. At this point, it will take weeks or months to determine whether or not activity will continue, pause, or cease entirely.

Given the long dormancy period, I suspect this was 'the opening act' for this volcano, and we can expect more frequent eruptions in the near future, as the structure of the mountain has surely been altered by the recent activity, meaning that cracks and fractures may allow for other lavas to erupt. 

You can keep up to date with Mauna Loa at the Hawaiian Volcano Observatory on the USGS site. 

Kilauea Erupts, La Palma Eruption Intensifies, Fagradalsfjall Quakes Raise Questions

 HAWAII, USA - Kilauea began a new eruption after weeks and months of inflationary tilt and occasional quake swarms. As of 3:20PM HST, USGS posted the following update:

"Kīlauea volcano is erupting. At approximately 3:20 p.m. HST on September 29, 2021, the USGS Hawaiian Volcano Observatory (HVO) detected glow in Kīlauea summit webcam images indicating that an eruption has commenced within Halemaʻumaʻu crater in Kīlauea’s summit caldera, within Hawai‘i Volcanoes National Park. Webcam imagery shows fissures at the base of Halemaʻumaʻu crater generating lava flows on the surface of the lava lake that was active until May 2021. 

The US Geological Survey Hawaiian Volcano Observatory (HVO) is elevating Kīlauea’s volcano alert level to from WATCH to WARNING and its aviation color code from ORANGE to RED as this new eruption and associated hazards are evaluated.   The activity is confined to Halemaʻumaʻu and the hazards will be reassessed as the eruption progresses. 

USGS volcano alert levels and aviation color codes are explained here: https://www.usgs.gov/natural-hazards/volcano-hazards/about-alert-levels 

The opening phases of eruptions are dynamic and uncertain. HVO continues to monitor the volcano closely and will report any significant changes in future notices. Stay informed about Kīlauea by following volcano updates and tracking current monitoring data on the HVO web page (https://www.usgs.gov/volcanoes/kilauea/volcano-updates) or by signing up to receive updates by email at this site: https://volcanoes.usgs.gov/vns2/. 

HVO is in constant communication with Hawai‘i Volcanoes National Park as this situation evolves. The eruption is currently taking place entirely within the closed area of Hawai‘i Volcanoes National Park. 

Hazard Analysis: This new eruption at Kīlauea’s summit is occurring within a closed area of Hawai'i Volcanoes National Park. Therefore, high levels of volcanic gas are the primary hazard of concern, as this hazard can have far-reaching effects down-wind. Large amounts of volcanic gas—primarily water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2)—are continuously released during eruptions of Kīlauea Volcano. As SO2 is released from the summit, it will react in the atmosphere to create the visible haze known as vog (volcanic smog) that has been observed downwind of Kīlauea. Vog creates the potential for airborne health hazards to residents and visitors, damages agricultural crops and other plants, and affects livestock. For more information on gas hazards at the summit of Kīlauea, please see: https://pubs.er.usgs.gov/publication/fs20173017.
Vog information can be found at https://vog.ivhhn.org/. 

Additional hazards include Pele's hair and other lightweight volcanic glass fragments from the lava fountains that will fall downwind of the fissure vents and dust the ground within a few hundred meters (yards) of the vent (s). Strong winds may waft lighter particles to greater distances. Residents should minimize exposure to these volcanic particles, which can cause skin and eye irritation. 

Other significant hazards also remain around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes within the area closed to the public. This underscores the extremely hazardous nature of Kīlauea caldera rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since late 2007."

The eruption is occurring within the summit lava lake which was recently formed in December 2020, when a small fissure poured into the water lake which had accumulated after the caldera forming collapse of 2018.  

The lava appears to have had no trouble in breaking through the still-cooling lava lake to 'reactivate' it, and is currently filling the caldera with newly erupted lava. This appears at this time to be a different fissure, perhaps related to a magma intrusion that occurred several weeks earlier.

From HVO, current thermal image of the Halemaʻumaʻu caldera with the new lava fountains.

Halema'uma'u erupting new lava into the May 2018 caldera, post 202 Dec eruption. 

Summit webcams can be found here: Webcams (usgs.gov)

LA PALMA, CANARY ISLANDS, SPAIN - The eruption of La Palma's Cumbre De La Vieja which began after months of low level quake activity continues with vigor, and as of yesterday, the lava flow is now entering the Atlantic Ocean. The events began with a bang, as on the central West slope of Cumbre De La Vieja (literally 'Old Summit' - which is a misnomer as this is the younger of two coalescing stratovolcanoes on the island), as a new pyroclastic cone has been constructed along several small fissures.

The unfortunate placement of this eruptive vent has destroyed hundreds of homes, cut across main highways and roads, and completely disrupted travel to and from the island. The government has promised swift and unimpeded aid to those displaced by the eruption. 

You can view a live feed of this powerful eruption here.

Live 24/7 coverage (in Spanish) can be seen here.

The last eruption on La Palma occurred some 50 years ago, at the Southern tip of the island, and lasted for several months. While it is too early to tell how long the current eruption may endure for, it could be assumed to be similar in duration.

REYJANES PENINSULA, ICELAND - The eruption at Mount Fagradals has gone into a quiet phase for about 10 days now, the longest pause since its 9 day hiatus weeks earlier. During this 'quiet' phase, tremor pulses have been erratic but weak. However for the past few days, a quake swarm has been rattling the region with small, but numerous temblors.

From IMO, the tremor at Fagradalsfjall is picking up. 

 

This has been interpreted in two ways: 1) It could be the 'death throes' of the eruption, signifying small internal collapses within the magma channel, and the readjustment of the crust surrounding it while it 'relaxes', or 2) It could mean that magma supply to the main vent at Fagradalsfjall has been cut off and the magma is trying to find a new pathway to the surface, presumably closer to Mt. Keilir, which was originally assumed to be a possible eruptive center.

Elsewhere in Iceland, the Askja (Ashes) volcano is displaying an abnormally high rate of earthquakes with accompanying deformation. The land has risen over 15cm within the last month, and shows no signs of slowing down. Icelandic geologists are installing more equipment to better monitor this very dangerous volcano, however they have been hampered by poor weather conditions in addition to its remote location.

And that's not all from Iceland... Several other volcanoes are beginning to show some warning signs including Katla, Hekla, Bardarbunga, and Grimsvötn. Grimsvötn's Vatnajökull glacier recently had a massive jökullhlaup (glacier outburst flood) which sustained for weeks, which has raised some concerns that the volcanoes of Vatnajökull are preparing for eruptions.

Quakes at Hekla, which are uncommon but can preceded eruptions, have been ongoing for quite a while, and scientists say that it is more pressurized than it was during its last large eruption. 

And surprisingly, there is even some geological action out in the Snaefellsnes Peninsula, where the volcanic system of Ljosufjoll is displaying seismic activity as well. The last eruption in this region was some 1000 years ago. 

Eruption at Fagradalsfjall Continues After Lull

 In Iceland, on the Reykjanes peninsula, the eruption at Fagradalsfjall entered into a 9 day dormancy, which caused some to speculate that the eruption may be ending. This was proven false several days ago, when rock fracture volcanic quakes, and a gradual increase in tremor resulted in a new phase in the eruption. Currently the volcano is 'pulsing' with activity that ranges from 10-15 minutes of lava effusion, and about another 15-20 minutes of quiet. This pattern has continued for several days now.

Today, a large lava breakout near the main erupting crater created a cascade of lava down into Natthagi valley (translated to 'Nigeria Valley' with online translation). 

The current view from Nigeria Valley. Courtesy of mbl.is.

Earlier, cameras trained on the volcanic crater also captured an individual scaling, then walking along the crater rim of the main vent, which was, to say the least, extremely foolish and a poor example for others. Icelandic authorities have had to repeatedly warn people not to tread on recently cooled magma both in Nigeria valley, but at Geldingadalur valley. 

Months earlier, one man, who later identified himself on social media, was spotted near the main crater narrowly escaping a sudden lava gush.

People should be reminded this volcano is unpredictable, and has shown to be hazardous in many ways. Gases that may seem to be blowing away from you could swiftly shift direction. Lapilli in the air can cause lung irritation. Lava breakouts, and new fissures are still possible. The very ground could open without warning, and issue hot gases and lava. Volcanoes are not toys, and they're not good for the 'Gram if you're dead.

End PSA.

Tremor plots currently show a high level of activity, and it is unknown whether the tremor plots currently being displayed are the result of a computer glitch, or if they are truly what is occuring. 

Krisuvik graph showing massive tremor range to the right. From Iceland Met Office. 

Fagradalsfjall graph showing more intense 2-4hz frequency amplitude.

As both graphs show similar data, it is probably not a data artifact, rather, the volcano is entering a phase of more fierce degassing after being 'clogged' essentially for over a week. Think of it a bit like putting your thumb on a hose filled with carbonated water. If you hold the hose upright, a gas chamber builds, and when released, the gas emission increases (which did happen), and then you get the mostly degassed liquid spouting out first, then the gassier liquid rises faster.

I expect this activity will continue until returning to the phase that was going on previously, with long, intense periods of lava effusion followed by long, quiet spells. But as many Icelandic scientists note, this is not a predictable eruption, and may be the first of its kind to be recorded in Iceland.

The magma source isn't coming from a magma chamber, rather it is coming from the mantle with a clear shot to the surface. Over time, the volcano may end up constructing its own main magma chamber. The past week's activity suggests some smaller ones may already be forming under the newly erupted lava, evidenced by today's outburst of lava from under the crust of the Geldingadalur lavas. 

Some scientists have speculated that even when activity in the main crater is not evident, magma is still gathering under the solidified lava.

In any case, the eruption continues to surprise scientists, delight tourists, and as far as eruptions go, this one has been mostly beneficial to Iceland. 

But please, for all that is sane and good in this world - DO NOT STEP ON THE LAVA.

Why The Eruption At Fagradalsfjall Is Unprecedented

 The eruption that began in Iceland's Reykjanes peninsula in March of 2021 has for the most part shocked scientists, volcano enthusiasts, and tourists alike. The volcano, it seemed at the time, was (or still is, depending on who you ask) part of the Krýsuvík-Trölladyngja system, which was experiencing its first magmatic eruption in some 800 years. The conventional wisdom at the time was that this was a relatively small eruption that would probably only last a few weeks. This has been proven wrong, the question now is why?

One need not look much farther than Iceland itself. Icelandia is a submerged continent who's geological history is incredibly complex. Until recently, Iceland was thought to be a volcanic hotspot underneath an oceanic spreading ridge. It turns out, that not only is Icelandia a continent, it may have existed since before the ridge, been submerged, only to split and have a hotspot form under it in the last several million years. 

This is significant, since original, ancient continental crust would provide more protection/insulation from magmatic intrusion, but since the continent of Icelandia drifted into (or was split in two by) an oceanic rift, the geology is unique. On one hand you have very thick crustal regions, and in the split middle, you have a thin layer of hardened material before you reach a mantle source, in some areas.

This explains in part the presence of stratovolcanoes on Iceland, as typically a stratovolcano is constructed by means of recycled or at least conglomerate material - mantle sourced, primitive magmas, mixing with more advanced, modern crustal material, which incorporates both H2O and organic components leading to explosive, tephra generating eruptions.

 Without any crustal 'recycling', you'd expect the entirety of Iceland, or at least most of it, to display mostly Hawaiian-style hotspot eruptions much like the current eruption at Geldingadalur. 

Back to Iceland's newest eruption, it has not gone according to conventional science, however there is precedent. 

A few days ago, Fagradalsfjall volcano had a brief period where ash was emitted, in what was thought at the time to be the end of the eruption. A similar event occurred at Kilauea, on the big island of Hawaii, at Pu'u'O'o crater. Magma had drained down rift, rapidly draining the small magma chamber under the spatter cone of Pu'u'O'o, and quickly, the roof of the chamber caved in, generating a rather interesting plume of ash, gas, and vapor. While magma has not yet returned to Pu'u'O'o, it can be reasonably assumed that it may, given the right circumstances.

Fagradalsfjall, however, is brand new! This is a magma dyke that has come from quite a depth, far deeper than any extant magma chamber in Iceland. It is not a magma chamber, rather it is a crack that goes down far enough to a mantle source, to build a magma chamber ABOVE land. It is building a new shield volcano. A Shield volcano forms layer-by-layer. The most famous example of which is probably Mauna Loa, the largest active volcano by volume in the world, on the big island of Hawaii.

Mauna Loa likely started life out just as Fagradalsfjall, as a minor crack in the ground, slowly growing and expanding, issuing fluid lavas, until a massive, shield-shaped mountain formed. Over millions of years, volcanoes like Mauna Loa grow their profile, building their own reservoirs of magma, and over time, building their own magmatic plumbing systems. The older they get, the less likely magma injections lead to eruptions (at least for most non-hotspot shields). 

Hotspot shield volcanoes, like Mauna Loa, however, can grow to immense proportions, and last for millions of years. While it is highly unlikely that the new volcano at Fagradalsfjall will be as dynastic as Mauna Loa, it is far, far too soon to tell.

What is clear, and what I will predict is that Fagradalsfjall (or whatever the official name for it will be in the future) is likely to be a very long eruption, with minor pauses, sometimes even months, in between. But this volcano is likely here to stay, providing Iceland with a bit of tourism excitement, but also questions in regards to how ti handles the eruption and disruption to infrastructure.

Already, Iceland has fought this volcano. It has constructed several dirt and rock berms by which to redirect the lava flows away from roads, homes and infrastructure. While the first two berms constructed did fail, several others appear to have learned from the previous berms, and have held. One is preventing the lava from spilling into a valley to the SW of the main vent, while the other is preventing lava from advancing towards the South Road highway, and several farm houses. 

Whether this is going to work or not is unclear, but one thing is certainly notable - Iceland is the only country that I am aware of to successfully fight and redirect lava flows when they threated critical infrastructure. This is quite an impressive feat, and civil engineers should take note. 

Today's activity at Fagrdalsfjall seems to consist mostly of lava-lake activity within the main vent, with some occasional overflows and large strombolian explosions. A new pattern has emerged in the past several days, from an easy-effusiveness to violent lava lake activity, followed by periods of outflow, then massive overflows. This is then typically followed by a period of perceived inactivity (although we cannot tell what is going on under the crater, it is assumed that 70% of the eruption and effusion is occurring out of view in underground lava tubes). 

The resumption of activity is typically begun by gas emissions, followed by the gradual appearance of lava fountaining, and eventual resumption of overflows. The time is not consistent between events, so it is unclear whether this is just a random 'sputter' or if the volcano is building up to something else, or building to an end. I suspect this will keep going on for several years, if not decades. But only time will tell.