Volcanic eruption in Iceland! It finally happened!
On Friday, the 19th of March 2021, a volcanic eruption began in the Reykjanes Peninsula, just a short drive from Reykjavík city. It’s the first time in almost 800 years we’ve had an eruption in this area. You’ve likely seen it in the news. Now get the inside scoop from Doctor Holly Spice for her second guest blog post on this active part of Iceland. Don’t worry, we’ll tag in at the end to discuss what this means for tourism in Iceland too and answer some of your frequently asked questions.
PLEASE NOTE: The volcano stopped erupting in September 2021, leaving behind a massive cooled lava field and smoking crater. Despite the lack of activity it’s still worthy of a moderate hike.
Doctor Holly Spice is a guide for Hidden Iceland and currently holds a PhD studying the geochemistry of Icelandic basaltic lavas. She first wrote about this volcanic site prior to the eruption. You can see her detailed thoughts on the imminent eruption here.
Guest writer: Dr. Holly Spice
It was first noticed on webcams and by locals to the Grindavík area as an orange glow that lit up the night sky. Over 50,000 earthquakes over a 3-week period preceded the eruption, regularly shaking Reykjavík and other nearby towns. The eruption began just as the earthquake activity seemed to be significantly decreasing, taking scientists and locals by surprise. One specialist had even been on the news earlier in the day reporting that an eruption was becoming less likely. Mother nature strikes again.
Volcanic Eruption in Iceland: The lead up
Over the past 3 weeks, locals and volcano enthusiasts around the world have been following the seismic activity, which was caused by the intrusion of a dyke, a 1-2m wide, 7km long vertical intrusion of magma into the crust.
The biggest question on everyone’s minds: will the magma make it to the surface?
That question was answered when the eruption began in Geldingadalur valley in the Fagradalsfjall hills, at 20:45 local time. This was the area that had seen the most intense earthquake activity as the dyke was intruded. The last time this particular area of Reykjanes had an eruption was over 6,000 years ago, and prior to the onset of the earthquakes 3 weeks previously, almost nobody would have considered it likely that this area would be the site of Iceland’s next eruption.
Initial Observations of the Volcanic Eruption
On Saturday morning after some preliminary scientific flights over the area, it was confirmed that a fissure of around 200m in length had opened and that an effusive eruption of lava was taking place. This was the first volcanic eruption in Iceland since the Holuhraun eruption in 2014 / 15.
In this type of eruption, fluid basaltic lava is steadily erupted by fissures and/or craters and then flows away from the eruption site to form a lava field. Volcanic ash seen in the other explosive main type of Icelandic eruption is not present, however the emission of toxic gases can pose a hazard around the eruption site.
A Visit To A Live Volcanic Eruption
By Sunday, it became clear that the authorities were not going to prevent the public from visiting the eruption site, so I decided to make the trip to Geldingadalur to see my first ever volcanic eruption in Iceland. In fact, it was my first volcanic eruption ever. As a geologist whose speciality is in the chemistry of basaltic Icelandic lava, this was a dream come true for me. Something I have been long anticipating, and of course, talking about on my tours. Seeing it with my own eyes wildly exceeded even my own very high expectations, and it is a day I will never forget for the rest of my life. 10/10 would go again.
On the walk to the volcano, you suddenly come over the rise of a hill and are greeted with a magnificent site, a crater throwing glowing hot lava into the air! I could not imagine a more perfect version of a volcano. If you asked a small child to draw a picture of one, they would draw exactly this.
How Does It Compare to Other Volcanic Eruptions in Iceland
The eruption at Geldingadalur is tiny compared to those produced by other Icelandic volcanoes. However it is precisely this that makes it so special and unique for those that visit it. It is possible to get so close to the crater that you can almost touch it (not recommended!). You can easily walk around the whole lava field in a few hours and view the eruption from all angles. The heat keeps you nice and warm, even in the Icelandic winter. It is extremely rare to be able to get so close to mother nature’s greatest and most fundamental process. It is truly a once-in-a-many-lifetimes experience.
Being so close, I was able to witness with my own eyes for the first time, many things I had studied in theory about eruption processes, but had never seen for myself. It brought many things I had learned at university to life.
When the lava is first erupted from the crater, it is fluid and glows orange. It then very rapidly cools in the air to form a hard brittle crust on the surface. This crust insulates the lava underneath and allows it to remain molten and continue to flow. Lava fields can cover huge distances in this way.
Lava types of this Volcanic Eruption
Both types of basaltic lava flow are present in the lava field. These are pahoehoe and a’a lava. Pahoehoe lava has a smooth or ropey surface and is formed by slow effusion of fluid lava. A thin skin forms almost immediately on the surface which is wrinkled and bunched into a ropey texture as the molten lava continues to flow underneath. The flow is slow enough that it does not break up the crust. Pahoehoe lava flows tend to be thin (up to a few 10s of centimeters) and consist of many overlapping thin lava flows.
A’a lava is formed where the effusion and flow rates of lava are higher. The brittle lava crust becomes fragmented and broken as lava flows beneath, resulting in a rubbly, rough appearance. As the lava front advances, the blocks are rolled along and tumble off the steep front of the lava flow and are then buried as the lava advances further. This produces a thick (up to 10 meters) lava flow, with a rubbly top and bottom. The rubbly top allows the interior of the flow to remain molten and continue to advance.
Crater Dynamics
Another interesting process to observe is the change and growth of the craters. When the volcanic eruption began on Friday night, there were 6 small craters on the line of the fissure all erupting lava. By Sunday, three of these craters had gone extinct and one large crater had taken over as the main source of lava. Two smaller craters also remained active.
One week later, one of the small craters has grown so much that it is almost the same size as the main crater. It is likely that the two craters will merge to form one large crater. The craters grow continually as the lava that is thrown into the air lands on the sides of the crater and cools, adding to the pile. Sometimes the side of the crater partially collapses allowing lava to suddenly rush out, however it quickly builds back up again.
Lava by Night
Not being satisfied with just one viewing of the volcano, I headed back on Tuesday evening to see it at night. If possible, this was perhaps an even more magnificent sight. The glowing lava field really comes alive in the dark and you see the lava channels in much more detail. I definitely recommend visiting in the dark if you get the chance. I could have stayed there all night watching the show. Unfortunately the area was evacuated due to dangerous levels of volcanic gas accumulating around the site as the wind dropped. On the drive home, the northern lights came out and I managed to capture them over the glow of the eruption in the distance. The Land of Ice and Fire at her finest.
A Long Lived Volcanic Eruption in Iceland?
There are several aspects of this volcanic eruption in Iceland that are cause for special attention. Firstly, the chemistry of the lava is very primitive, which means it is close in composition to the mantle that melted to form it. The lava comes straight from the mantle (the gooey, hot interior of the Earth that underlies the crust), from a depth of 15-20 km and is not stored in the crust in a magma chamber on the way to the surface.
Lava on Reykjanes is usually fairly primitive, however such primitive compositions as this have not been observed in Iceland for around 7,000 years. Lavas with similar compositions are found in shield volcanoes that were erupted soon after the glacial ice-sheets retreated. Shield volcanoes are low-angled volcanoes that resemble a Viking shield and can be active for many many years.
In addition to the chemistry, the eruption rate of the lava has been remarkably steady since it began. Both of these observations have led specialists to suggest that this could be an eruption that lasts for many months or even many years. Perhaps then you don’t need to worry that you are missing out! If we are lucky, the eruption will continue after COVID-19 restrictions are lifted and international visitors will get a chance to see the eruption for themselves.
However, before you get too excited, I would like to caution that the eruption is barely a few weeks old, and scientists are far from being sure about this. The eruption could also die out within the coming days. Volcanoes are notorious for being continuously surprising and hard to predict. The only thing we can do is cross our fingers and wait to see how the situation plays out.
What does this mean for tourism in Iceland?
Hidden Iceland tagging in to answer some of your frequently asked questions (updated 12th February 2022)?