The volcanic silly season seems to be going strong now. And with silly season I mean miniature eruptions, unconfirmed eruptions, unconfirmed Jökulhlaups and so forth. These are of course interspersed with real eruptions and Glacier floods. Let us go through them.
There have been reports of sulphuric smell and unusually coloured water coming out of Hofsjökull glacier towards the northwest. According to witnesses the water is containing silt or mud. There are no reports of an increase in the water flow as of yet, but the changes in color might mean that there is a Jökulhlaup on the way.
Hofsjökull is the largest volcano in Iceland that in any way can be called active. It has an 11 by 7 kilometer large caldera. The volcano has had early Holocene eruptions with formation of a shield volcano and basaltic fissures extending from the glacier. The highly hydrothermally active Kerlingarfjöll is also considered a part of the Hofsjökull volcanic system; it is though not situated under the Hofsjökull glacier.
The change in the water is most likely due to an increase in hydrothermal activity either inside the massive caldera, or in one of the fissures extending to the northwest.
Activity continues at the Kverkfjöll volcano after the phreatic detonations that took place around the 16th of August. A few smaller earthquakes have taken place in the area, and a Jökulhlaup is still ongoing from the area. This is though not a significant Jökulhlaup and will subside as the available water drains out of the caldera.
Early in the morning today a 2.7M earthquake took place under the volcano at a depth that might indicate movement of magma at depth (9.1km).
Skaftá West Cauldron
The western cauldron that drains out into the Skaftár River is filled to the brim and a medium sized Jökulhlaup is expected at any time. The western cauldron normally suffers from smaller jökulhlaups compared to the eastern cauldron. The cauldrons are small caldera like structures at the Loki-Fögrufjöll volcanic system and the ice lakes are driven by strong hydrothermal activity.
It is slightly out of the ordinary, but not unheard of, that 3 different volcanic systems are suffering from Jökulhlaups at the same time. There though seems to be different driving forces behind them, at least as far as we know at this time.
Iliwerung volcano is a caldera flanking somma volcano on the southern rim of Lerek Caldera on the Indonesian Island of Lomblen. The last sub aerial eruption of Iliwerung was in 1952, that eruption ended a period of heightened volcanic activity that saw 7 eruptions during 4 years. The phase started with an emplacement of a dome named Iligripe on the southern slope above the ocean in 1948.
In 1973 a new phase started at the volcano when a sub-aquatic vent named Hobal opened up and 3 small ephemereal islands surfaced.
Two days ago reports came that the vent of Hobal was once again erupting. On the 19th more than 180 earthquakes took place under the flank of the volcano at Hobal. Locals reported changes in water color and that steam rose in the morning of the 20th to a height of 1000 meters. Locals also stated that glow was visible.
I have a couple of big question marks on this by now widespread report. First of all, NVI has only raised the volcano from 1 to 2 on their scale (1 to 4) due to the earthquakes, but has as of yet not raised it further or published an official report on the eruption. There is also no evidence of an ongoing eruption from satellite imagery. The reports of glow from a the submarine volcano might also be a bit problematic.
Something tells me that some of our commentators will find out if this volcano is actually erupting, or not.