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Etna update, 09.12.22:

Effusive activity at the northeastern base of New Southeast Crater continued last week. While the tremor remained elevated, seismic activity increased slightly.

Effusive activity continued at the northeast base of New Southeast Crater last week. The released lava flow, which remained relatively narrow, continued to move into the Valle del Leone, reaching a length of about 600 m on 08 December. Meanwhile, some gas was persistently emitted in the summit area of the New Southeast Crater. I could not observe any explosive activity. Light sensitive webcams sometimes showed faint glow on the upper northern flank of the cone, where an explosive vent was active in May/June.
Bocca Nuova continued to release gas in pulses during the last week. At Voragine and Northeast Crater there was only minor gas emission.

The INGV reports that the effusive vent, which opened on 30 November, is located at an altitude of 2900 metres. The lava flow released by the vent moved parallel to the lava flow emitted from 27 November and had a length of 450 m on 30 November. Its front moved on 2700 m high terrain [1].

The analysis of the data from the GPS stations showed the continuation of the inflation of the volcanic edifice in November [1].
The clinometric data showed a rapid change in the slope in the summit area of one microradian on 15 September [1].

Infrasound activity at the summit craters was moderate in November and the amplitudes of the events were low. The source of the activity was Bocca Nuova [1].

Sulphur dioxide emissions at the summit craters increased somewhat in November. The mean emission rate reached average levels.
Ground carbon dioxide emissions (ETNAGAS station) were at average levels in November.
The concentration of helium isotopes (3He/4He ratio) in the Etna area, which was last determined on 24 November, was lower than in the previous month with a value of 0.57 and was at an average level [1].

The online seismograms of the ECNE station were characterised by slight noise during the past week due to the increased tremor. Weak long-period signals were frequently observed.
The tremor was at a medium level last week and was subject to only slight fluctuations [2].

On 02.12. and 03.12. two weak quakes occurred near Sant'Alfio (eastern flank), the strongest having a magnitude of 1.6. On 07.12. two quakes occurred east of Sant'Alfio, with magnitudes of 2.5 and 1.4. On 08.12. an earthquake of magnitude 2.5 was registered south of Paternò (southern flank). On 08.12. an earthquake with a magnitude of 1.5 occurred near Mangano (eastern flank) [3].

My interpretation of the data and speculation about further developments:
The slight increase in seismic activity, which had recently been particularly concentrated on the eastern flank of Etna, as well as the continuation of the inflation of the volcanic edifice indicate, in my opinion, that magma continues to be stored in the mountain. The relatively weak effusive activity that has continued over the past week is unlikely to provide much relief in this regard.
Most of the gas from the rising magma is likely to escape via Bocca Nuova. As long as there is not a large amount of fresh magma rising, I do not expect explosive activity at the South East Crater complex.
Therefore, I think it is most likely that the purely effusive activity at the New South East Crater will continue. However, new vents could open further north or east at any time. A reduction of the effusive activity or a slow cessation of the eruption is also possible.

1 - INGV-Sezione di Catania. 2022. Etna - BOLLETTINO MENSILE MESE DI RIFERIMENTO NOVEMBRE 2022
2 - INGV-Sezione di Catania. 2022. Home. TREMORE VULCANICO. ECNE
3 - INGV. Osservatorio Etneo. Sorveglianza e Monitoraggio. DATABASE TERREMOTI. Localizzazioni di sala operativa. 2022.

Today, I look back to 15 July 2006, the day when a new eruption of Mt Etna startet after almost two years of quiescence. And it was just on this day that I arrived for a short holiday on the mountain and was able to observe an eruption at close range for the first time. The lava. The smell. The sound. Oh, what a day!

Etna update, 02.12.2022:

Since 27 November, lava has been erupting from the north-eastern base of the New Southeast Crater. This forms a short and narrow flow that is heading towards Valle del Leone. The tremor was temporarily increased and seismic activity is slightly enhanced.

Bad weather with fresh snow frequently hindered observations of the summit craters via webcams during the last 14 days. During the few cloud-free hours, Bocca Nuova continued to show the usual gas emissions, which were still strong and mostly intensified in pulses.
At Voragine and Northeast Crater, no significant gas releases were visible.
At the Southeast Crater complex, some gas was persistently emitted from the central area between the new and old Southeast Crater. In the northern summit area, fumaroles continuously released some gas.

After a stormy and cloudy day, the clouds slowly cleared on the evening of 27 November around 17:30 and suddenly a small thermal anomaly was visible on the Cagliato thermal cam. This was localised at the northeastern base of the New Southeast Crater. A little later, other webcams also showed several small glowing spots in this area, which is located at about 2800 m altitude. In the course of the evening, the glow intensified a bit more and a short lava flow was visible, slowly moving north/northeast towards the Valle del Leone. On the other hand, I was not able to see any glow in the summit area of the New Southeast Crater, but the cone was also often hidden in clouds.
During the night of 28 November, the lava emission continued, but the lava flow hardly progressed. On the morning of 28 November, around 06:30, only a little glow could be seen at the effusive vent. Later, clouds moved in and lingered until 29 November. However, no more activity was visible through some gaps in the clouds.
In the evening of 29 November, glow was again visible at the northeastern base of the New Southeast Crater from about 19:30. The Cagliato thermal camera also showed a small thermal anomaly a little later. Again, lava poured towards the Valle del Leone. In contrast to the eruptive event of 27 November, this time the tremor also increased significantly and reached almost high levels. The effusive vent was located slightly more slope upwards on the NE flank of the New Southeast Crater than during the 27 November eruption.
During the night of 30 November, lava emission continued, but the lava flow gained length very slowly. After the clouds cleared in the evening of 30 November, the northeastern base of the New Southeast Crater continued to show glowing spots. Effusive activity continued on 01 and 02 December. Meanwhile, only gas was emitted from the summit area of the New Southeast Crater. Explosive activity could not be detected.

On 30 November, INGV reported that the lava flow at the New Southeast Crater had reached a few hundred metres in length. Furthermore, it was reported that the source of the tremor was located between Southeast Crater and Bocca Nuova at an altitude of 2000 - 2600 m. Infrasound activity at the summit craters was low and concentrated at Bocca Nuova. No noticeable ground deformations were recorded at the volcanic edifice [1].

The tremor fluctuated at a medium level until 29 November, reaching nearly high levels only on 19 and 27 November. On 29 November, tremor began to rise rapidly and remained just at a high level until 30 November. Afterwards, the tremor oscillated between medium and high intensity several times and stabilised at medium level from 01 December [2].

On 19.11. a quake of magnitude 1.5 occurred east of Monte Nero (NE flank). On 19.11. a quake of magnitude 1.6 was measured northwest of Piano Pernicana (NE flank). On 25.11. two quakes occurred in Piano Pernicana, reaching magnitudes of 1.7 and 1.9 respectively. On 25.11. a quake of magnitude 2.1 occurred west of Randazzo (NW flank). On 28.11. a quake of magnitude 1.5 was recorded near Randazzo [3].

My interpretation of the data and speculations about the further development:
Now the magma has managed to make its way to the surface of Etna after all. After the presumed magma rise on 15 November, which I speculated about in my last update, the pressure in the mountain must have become a bit too great. Since the lava seems to flow out very quietly and there has been no explosive activity in the summit area of the Southeast Crater complex so far, it is probably already relatively strongly degassed magma. It has probably been rising for months (since the end of the last eruption in June) and is being degassed via Bocca Nuova. The recent increase in seismic activity, especially in the area of the Pernicana fault, may indicate that magma has accumulated in the area to the east of the summit craters and/or beneath the northeastern rift system. This has now created a path upwards and is likely to emerge until the pressure inside the mountain is equalised again. Since the vent is still relatively far up and will not be very large, I do not think a prolonged eruption is to be expected. However, it could happen that new effusive vents open further north or northeast, which would then also be located on somewhat lower altitude. Then a longer eruption is also conceivable. Of course, the magma rise can intensify at any time, or fresh and gas-rich magma can ascend. This would be a game changer. At the moment, however, there are no indications of this.
So I think it is most likely that the quiet and low lava production will continue for a few more days and that the narrow lava flow will gradually pour into the Valle del Leone.

[1] INGV-Sezione di Catania. 2022. Comunicati attività vulcanica. 30/11/2022 12:56 - COMUNICATO ETNA

[2] INGV-Sezione di Catania. 2022. Home. TREMORE VULCANICO. ECNE

[3] INGV. Osservatorio Etneo. Sorveglianza e Monitoraggio. DATABASE TERREMOTI. Localizzazioni di sala operativa. 2022.

Renewed eruptive activity at Mt Etna:

On the evening of 29.11.2022, the INGV webcams showed the production of lava at the northeastern base of the New Southeast Crater from about 18:30 UTC. The emission of lava in this area, located at an altitude of about 2800 m, had already started on the evening of 27 November, but then stopped again on 28 November. This time, the event was also associated with a significant intensification of the tremor, which reached almost high levels.
At 20:15 UTC, lava production continues and a short, narrow lava flow moves northwards towards Val del Leone.

Source: My own observations via webcams/website INGV

Here is a photo that I took on 07.07.2021 showing a short but very violent eruption (paroxysm) of Mt Etna's South East Crater.

#volcan #volcano #Etna Un petit évent éruptif s'est ouvert le 27 novembre au soir, vers 18h15 (heure locale), à l base du versant nord-est du Cône Sud-Est. Une petite coulée de lave a été produite/A small éruptive vent opened on the evening of 27/11, at the north-east foot of the South-East Cone, with formation of a small lava flow

@EtnaUpdater
ETNA PRESS RELEASE
The National Institute of Geophysics and Volcanology, Etneo Observatory, announces that starting from 17.00 UTC the video surveillance network, when the cloud cover that insists on the volcano has thinned, has highlighted the opening of an effusive vent at the north base. east of the SE Crater, at an altitude of about 2800 m a.s.l., from which a small lava flow is emitted that slowly advances towards the desert Valle del Leone.

1/2

Eruptive activity startet at Mt Etna today:

Bad weather with fresh snow and storm prevented the observation of Etna via webcams the whole day. But around 17:30 (UTC), glow was visible at the eastern to northeastern base of New Southeast Crater at about 2800 - 3000 m altitude. Due to the bad weather conditions, I cannot yet say whether an eruptive fissure has opened there or if lava is moving from further up of the South East Crater. The tremor continues to fluctuate in the medium range with short spikes to just above high level.

Tourists (including me) climb Bocca Nuova (one of Etna's summit craters) in July 1979, after being taken by all-terrain vehicles to a car park at the base of the cone.
Just two months later, on 12 September 1979, a sudden explosion happened in the Bocca Nuova. Lava blocks were ejected, killing 9 tourists and injuring 22. This tragedy put an abrupt end to the mass tourism that had been practised there until then.

How about a revival of in the Fediverse? I will start, of course with a photo of : the South East Crater from the south flank in June 2022.

So this is my first post on Mastodon.

Part of my work as a volcanologist with the Italian National Institute of Geophysics and Volcanology (Istituto Nazionale di Geofisica e Vulcanologia, INGV) is the real-time surveillance of seismic and volcanic activity in the volcanic areas of Sicily. This is done in 8-hour shifts in the Operations Room of the INGV seat in Catania, the Osservatorio Etneo. This is me making a stupid face during my latest shift, on 5 November 2022.

update:

On 15 November 2022, Etna experienced a significant uplift in the summit area, which was accompanied by strong fluctuations of the tremor, as well as some weak earthquakes. However, there was no eruptive activity or other visible events.

In the past 14 days, gas emissions at Etna's summit craters continued to be concentrated at Bocca Nuova, where there was vigorous and pulse-like gas release.
At the Southeast Crater complex, some gas was persistently emitted from the breach or the central crater area. Some gas was also persistently emitted from the northern summit area of New Southeast Crater. A hot spot on the inner western crater wall of the breach was visible as a small glowing spot during the nights.
At Voragine and Northeast Crater, the webcams continued to show little significant gas release.

As reported by INGV, a significant change in the clinometric readings occurred in the early morning of 15 November. The first change occurred between 01:00 and 01:30 and the second between 03:50 and 04:30. In total, there was a change in the slope of almost one microradian, indicating an uplift that occurred in the area of the summit. At the same time, the DRUV station on Monte Ruvolo (western flank) showed significant variations in dilatometric data. No changes occurred after 05:00 [1].

The online seismograms of station ECNE were characterised by persistent noise during the phases of increased tremor, which wiped out most of the other signals. Otherwise, long-period signals appeared regularly.
The tremor decreased somewhat from 06/11 and then fluctuated at a medium level. On 14/11 there was a rapid increase to a high level, before the tremor temporarily dropped rapidly to a low level on 15/11. It then rose rapidly in the evening of this day, just reaching high level and staying there for a few hours. On 16/11 tremor declined with fluctuations and stabilised at a medium level [2].
In the evening of 15/11 the source of the tremor was located below Bocca Nuova at an altitude of about 3000 m [1].

On 07/11 two earthquakes occurred west of Bronte (northwest flank), reaching magnitudes of 1.7 and 1.9, respectively. On 12/11 a quake of magnitude 1.6 occurred in Piano Pernicana (northeast flank). On 12/11 a quake of magnitude 1.7 was registered southeast of Paternò (south west flank). On 15/11 several very weak (magnitude less than 1.5) quakes occurred in the area of the Southeast Crater complex. On 15th and 16th November two quakes occurred in Piano Pernicana with magnitudes of 1.5 and 2.0, respectively [3].

My interpretation of the data and speculations about the further development:
Probably a larger amount of magma temporarily rose on 15th November, as the clinometric data showed a rapid and significant change in the slope of the mountain flank in the early morning of that day. In addition, several weak earthquakes occurred simultaneously at the Southeast Crater complex. Afterwards, the tremor, which had been elevated for months before, dropped significantly. Since there was no eruptive activity, it can be assumed that the rising magma was stored inside the mountain. It probably spread along the rift zones. At least the Pernicana fault on the northeast flank reacted to the changes in the mountain with some weak earthquakes. It is therefore conceivable that the magma migrated north/northeast from the Southeast Crater complex towards the northeast rift zone. After a temporary strong and rapid increase of the tremor, it has levelled off again at a medium level. The situation has thus returned to normal since 16 November. It is quite possible that the event of 15 November is the prelude to further similar events. Therefore, in my opinion, the probability of the return of eruptive activity within the next few weeks, especially at the Southeast Crater complex, has increased significantly.

Sources:

1 - INGV-Sezione di Catania. 2022. Comunicati attività vulcanica. 15/11/2022 19:47 - COMUNICATO ETNA
2 - INGV-Sezione di Catania. 2022. Home. TREMORE VULCANICO. ECNE
3 - INGV. Osservatorio Etneo. Sorveglianza e Monitoraggio. DATABASE TERREMOTI. Localizzazioni di sala operativa. 2022.


Burial mound near (Hesse/Germany) from about 500 BC . The stone statue of a Celtic chieftain and gold grave goods were found here.


Some weak earthquakes at shallow depths at the Southeast Crater complex last night. Then a sharp decrease in tremor amplitude. Now again a strong increase of the tremor. I wonder what the old lady is brewing up?

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