This is a short update on the eruption in Fagradalsfjall mountain that is part of Krýsuvík-Trölladyngja volcano system.
- New crater has been confirmed in the eruption in Fagradalsfjall mountain. This crater started to form few days ago. It follows the activity in the largest crater and remains inactive during the time period when there is no activity in the large crater.
- This new crater is going to change lava flows in the eruption and restart lava flows in the south-Meradalir and Geldingadalir.
- Current the new crater is building up. It is on the larger crater rim and might be unstable and collapse are likely to happen.
- Formation of new craters following the formation of this crater is likely. When and where new craters form is impossible to know in advance.
- It is a question if this is a new phase of the eruption. I currently don’t have an answer.
- The new crater is visible on all the web cameras.
Fog has been blocking the view of the eruption today and I expect that is going to be the case tomorrow (17-August-2021) and maybe next few days. This fog makes it difficult to see what is going in the eruption.
mbl.is has a good view today as they have a cam that’s close.
https://www.youtube.com/watch?v=ZHZ9LU4vpf4
The ever changing eruption. Very cool.
Looks like a third has now opened up.
Next eruption should confirm if that is the case. If so, then I wonder how much fissure activity is going on under that huge mound of lava? Guess the cracks on “Theater Hill” were a very tell-tale sign.
The harmonic tremor is on its way up. It can be seen here. I made this website to keep track of it. There where at least two new craters when the eruption stopped during the night.
http://skjalfti.com/tremor-index.html
http://skjalfti.com/tremor-fagradalsfjall.html
It seems that this is some kind of hornito, a transient, rootless vent like that seen in the crater of Ol Doinyo Lengai in Tanzania (parasitic cone may be too strong of a word even). Crater doesn’t accurately describe this feature, which is transient and seems to lack an independent conduit to the intruding dike in the subsurface—definitely not a separate fissure. The lava and gas supplying it seems to be coming from some unknown depth in the lava lake, possibly through tubes that were roofed over/encrusted down the side of the cone from prior “lava falls”.
Check the timelapses of this feature forming repeatedly over the past few days, in different guises as a simple “hole”, “lavafall”, and finally “hornito”.
Aug 13-15: https://youtu.be/lra3C74ZFMo
Aug 15-17: https://youtu.be/8qG5-gb2QGE