ERUPTION In Iceland! Fagradalsfjall ERUPTS

 About 1 hour ago, Mount Fagradalsfjall erupted. Some webcams are able to see the eruption including this one. Color video (not the best shot) can be seen here. A camera from RUV.is is here. 

Location of the new fissure from MBL.is

A massive glow can be seen above the mountain, in the area that was predicted to be the most likely spot for an eruption to occur. 

Fissure vent is feeding pahoehoe lava flows.

Screengrab from the IPCAMLIVE 

Image from Icelandic Coast Guard chopper aerial flight. 

A helicopter is apparently flying around as can be currently seen in webcam video.

While it is nighttime, it is impossible to see how high the lava fountaining is at the moment.

The Iceland MET Office has confirmed the eruption.

As stated in a previous post, it is not uncommon for quakes to stop, or slow once an eruption is imminent, and that was the case here. Seismicity dropped to lower levels with very few large quakes. Some scientists believed that an eruption would not occur. Others are theorizing that this may be a new phase for the entire peninsula. Seismicity is still quite low, even with lava now escaping to the surface.

Current seismicity remains lower than the last several weeks.

It is not known how long this eruption may last for, or where the new lava flow models predict that lava will go. We will likely know more once the sun rises in Iceland and more coverage begins. 

There are a few possibilities:

- The eruption is short-lived, lasting only hours to days

- The eruption gains a steady, deep supply of magma and erupts for weeks, months, or years

- The eruption occurs in phases, in fits and starts, until ceasing altogether

As magma is theorized to still be coming into the dyke system, this eruption will likely at least last for a week or two, although it is anyone's guess at this point.

Currently, the magma appears to be fast-flowing pahoehoe style lava, similar to Hawaiian eruptions. Lava this fluid may travel fast.

I will update this post separately from my previous post on the quake swarm, as an eruption is now underway, however if you'd like to refer to the lead-up to the eruption, you can see my previous coverage here. 

*****UPDATE 3/21/2020*****

The eruption at Fagradalsfjall continues. It is as expected, a low-threat eruption with little to no ash emissions. Iceland has cancelled the aviation warning. Many people are showing up to the sit to view the eruption up close. While the eruption may seem safe, this is not advised. New cracks, fissures, or vents can open at any time, as was the case in the Leilani Estates fissure eruption on the Big Island of Hawaii. People should avoid the area, and only take helicopter tours if possible. Of course, you cannot completely deter thrill-seekers, and this would be difficult to control around the clock.

The lava cone that has become the main vent collapsed earlier, spilling out a large pahoehoe flow which is advancing off-camera at ruv.is. It is unknown at this time whether this means the lava flow has found a new outlet and will drain further out of the main area. As lava flows cover the initial zone, it will create ledges, and lava will find a way to its lowest point. If the lava flows continue for weeks or months, it will likely flow to the lowest area it can find. 

This part of the eruption is expected to last from days to weeks, but probably not much longer unless another large injection of magma feeds into the current system. Flow rates fluctuate slightly, but overall the eruption appear consistent in its flow rate. 

Minor Strombolian and major pahoehoe effusive activity is occurring at the moment, with little to no change since the onset of eruption, although the number of active vents has now been reduced to around three or four. 

The fact that pahoehoe is the main product of this eruption strongly suggests a mantle source, as this would not be 'old' magma erupting as lava, however that is yet to be determined by volcanologists. Lava samples are needed to determine crystallization, gas, and other metrics to show whether this is older lava that has been forced up by newer magma, or if this is a mantle sourced 'new' channel. 

*****UPDATE 3/22/2021*****

The eruption continues at Fagrdalsfjall. The new eruptive center has been named for the Geldingadaulur valley, which roughly translates into 'Castration Valley' in English. While the eruption has occurred in Fagradalsfjall Pleistocene volcano, some sources theorize that the eruptive fissure is sourced from the more recent Krysuvik-Trolladyngja volcanic system, some miles to the East. However this is yet to be determined, as no chemical analysis is yet available, and data is still coming in.

What we do know at this point, is that base don historical data, activity in Reykjanes peninsula seems to come in long phases, followed by long periods of rest. It seems that the last period of rest is over. Some volcanologists and bloggers suggest that this could be the start of a new 'volcanic dynasty' in Reykjanes, or that eruptions should take place nearly every year for the next several hundred years. 

I do not share that assessment, although it is too early to tell. In my own opinion, volcanism from this vent will continue for several weeks, to perhaps more than a month, followed by a period of quiet, perhaps more than several years, before another monogenetic event breaks out. This might continue for a couple of decades or so, with rare, but predictable events occurring down the peninsula. However there is no concrete evidence at this time that points to a prolonged volcanic period on the peninsula.

I of course could be flat wrong here, however I don't think that current events indicate a 'major' change in activity, but perhaps a rare avenue for a minor magma surge to emerge and create a spectacle. 

This of course could change if major activity resumes after the eruption halts, or if a major tectonic event opens up wider avenues for magma to flow up to the surface. In any case, the current spectacle is simply amazing, and fun to watch. It is fortunate this eruption has not impacted any communities, and provided a bit of excitement for locals and media during what is probably the worst last couple years in human memory with the misery of COVID-19. 

You can watch the eruption on YouTubelive from RUV.is below.

*****UPDATE 3/23/2021*****

A mantle source for the lava currently being erupted in Geldingadaulur has been confirmed, which completely changes the calculus for Iceland regarding the eruption. Fluid lava is issuing at a steady, if not increased pace at the current vent area, which now consists of a ~400 meter high lava cone (prone to frequent collapses yesterday), with an insulated lava vent on its side. A second vent opened up (to the left on the above camera) which is vigorously issuing lava at around the same rate as the 'main' vent. 

It is now being theorized that due to the steady effusion, and fluidity of the magma, that this comes from a mantle source some 40-km deep (or deeper), and that this magma freshly broke through the crust, and could be a distinct magmatic system from nearby volcanoes like the Krysuvik-Trolladyngja system. 

If this is true, Iceland could be in for a very long eruptive period with a shield-building event not unlike the long eruptions in Hawaii. When magma finds a steady channel to the surface, there is not a lot that will stop it from continuously flowing to the surface. The only things that could stop the eruption would be that magma injection slows to the point it can no longer erupt, and the dyke that was feeding the lava to the surface cools. This does not appear to be a likely outcome any time soon. If anything the rate of flow has increased since the onset of the eruption.

The other option is that this is a long-lived monogenetic event that persists for years, not unlike the Paricutin eruption in Mexico.

Gas in the area is now extremely hazardous as the winds have died down somewhat, and the lava field grows. Icelandic authorities are having to station police and emergency personnel near the eruption site to keep people from getting lost, or putting themselves in danger to see the volcano. It is advised that if you want to watch the eruption, simply stream it rather than putting yourself at risk.  

New satellite imagery of the eruption site was also released by MBL.is today (image below)

NASA image of the eruption site.

*****UPDATE 3/24/2021*****

The eruption at Fagradalsfjall/Geldingadaulur continues. Effusive eruption continues at a steady rate, with no signs of weakening as of yet. Pulses of extremely vigorous emission have been observed. There have been several instances of lava tubes forming on the flanks of the main cone, which is now joined to a more vigorous, elongated vent which is just as active as the former main vent, if not more so.

The lava is pooling in an area with no outlet at the moment, so over time, lava channels will probably redirect the the lowest point on a perched table, which may speed up lava advances to lower valleys like the originally speculated eruption location of "The Night Pasture", or Nátthagi valley (Icelandic translation is not perfect here). If lave begins to enter this valley, it would likely become a main exit for new flows, but that of course could change if vent structure does. 

For now, the lava is pooling in a relatively safe area, with no threat to infrastructure or residents. It could probably not have erupted in a more convenient area, which is quite fortunate for the town of Grindavik, which is the nearest to the eruption site. 

*****UPDATE 4/1/2021*****

The eruption continues, with no sign of slowing down in terms of lava output. Tremor remains variable, and several quakes of up to magnitude 2.9 have occurred in the last several days. No news yet on whether deformation changes indicate any change in the rate of eruption, or any indication of whether or not this will continue for a long time.

Geldingadaulur vally is nearly filled with lava. A recent article by MBL.IS has posted the below photo of the current amount of lava filling the valley as seen on 3/31/2021. 

Photo from RUV.IS showing the extent of the lava in Geldingadaulur valley.

The eruption will likely continue until the magma pressure is cut off, and the surrounding cooler rock solidifies the magma dyke. If the eruption continues, with mantle driven magma, there is every chance that the dyke will erode and melt its boundaries, becoming wider. If this indeed mantle driven magma from a deep source, this could indeed create a larger magma channel over time, if the pressure persists.

If a new, large magma channel is formed, this can create a shield volcano over time. Although it is too early to tell, some have speculated that this is the birth of a shield style eruption.

However, it should be noted that a similar eruption in Mexico of the Paricutin volcano, was similar in many ways. This could be a 'monogenetic' event where a new lava/spatter/cinder cone/lava dome is formed, and never erupts again. 

The Reykjanes Peninsula is riddled with monogenetic cones with large lava flows. It stands to reason that this eruption might not be much different. But with volcanoes, and mantle-driven sources, the proof is only in the results, as we cannot truly see deep enough to know what to expect. This could end up being a very long eruption, the tip of something bigger, or a small eruption that entertained Iceland and petered out after several months or years. 

Hopefully, in the coming weeks and months, more and more data metrics will give a clearer picture of the mechanics of this eruption, and enhance volcano science for the better. It has been a long time since humans have witnessed a 'new' volcano being born, even if all of Iceland is in fact volcanic in origin. This remains an exciting event.