EtnaUpdater @EtnaUpdater@qoto.org
Volcanophilic nerd & #volcano hiker blogging about Mt #Etna since 2004. Find tweets about Etna and also my backyard geology, the #Vogelsberg area.
Joined Nov 2022
Etna update, 03/02/2023
Last week, the effusive vent at the northeast base of Mt Etna's New Southeast Crater continued to release lava. However, the flowrate fluctuated significantly.
On 28.01., the front of the lava flow initially stagnated at about 2300 m altitude. On 29.01. it retreated to the rim of Valle del Bove at about 2500 m, but during the day a new partial flow developed, which now took a slightly more southerly course. On January 30, the southern branch descended a few hundred meters down the escarpment of Valle del Bove, and the northern branch also became better fed. On January 31, the flows stagnated or retreated again. On the other hand, the southern stream was well fed on 01 February and widened significantly. During the night of February 02, the lava flow decreased significantly and during the day practically no strong thermal anomalies were visible. Towards evening, however, a new surge of lava set off again. Today, the new lava flow continued to move slowly northward through the Valle del Leone.
Meanwhile, in the summit area of the New Southeast Crater, gas was emitted persistently, but in contrast to the previous week, only few ash was visible. Instead, pulsating glow was visible in the upper northern section of the cone during the nights on light sensitive webcams. Presumably, the escaping steam was illuminated from below, from the depth of the vent. Whether this was caused by deep-seated explosions or simply by heat remained unclear.
During last week Bocca Nuova released the most gas of the summit craters. Again, the emissions were pulse-like enhanced and at least once a gas ring was observed. At Voragine and Northeast Crater only weak gas emission was visible.
As reported by INGV, a volume of 4.4 to 5.6 million m3 of lava was emitted by January 29. This occupied an area of about 880,000 m2 [1].
The analysis of the data from the GPS stations showed no significant changes for the period between January 23 and 29. However, the slight deflation already observed in recent weeks continued [1].
Clinometric data showed no significant changes between January 23 and 29 [1].
The measurement of infrasound activity at the summit craters in the period between January 23 and 29 showed a low number of events. However, there was a slight increase in explosive activity in the last days. The source of the events was the Bocca Nuova [1].
Sulfur dioxide emissions at the summit craters were at intermediate levels during the period between 23 and 29 January.
Ground carbon dioxide emissions (station ETNAGAS) decreased slightly between 23 and 29 Jan, reaching low levels [1].
Weak long-period signals were occasionally visible on the online seismograms of station ECNE during the past week [2].
The tremor fluctuated in the lower range of the mean level during the last week and was subject to a slight increasing trend during the last days [2].
As reported by INGV, the source of the tremor in the period between 23 and 29 January was at about 2400 - 2800 m altitude in the area below Southeast Crater [1].
On 28.01. an earthquake of magnitude 1.7 was registered at Pizzi Deneri (northeast flank). On 02.02. an earthquake of magnitude 2.0 occurred at Pozzillo (eastern flank) [3].
1 - INGV-Sezione di Catania. 2023. Etna - BOLLETTINO SETTIMANALE - SETTIMANA DI RIFERIMENTO 23/01/2023 - 29/01/2023
2 - INGV-Sezione di Catania. 2023. Home. TREMORE VULCANICO. ECNE
3 - INGV. Osservatorio Etneo. Sorveglianza e Monitoraggio. DATABASE TERREMOTI. Localizzazioni di sala operativa. 2023.
At the eruptive fissure of 2008, Mt Etna May 2009
Etna update, 27/01/2023
During past week, lava continued to be released at the northeast base of Mt Etna's New Southeast Crater, but the production rate was subject to strong fluctuations. Tremor and seismic activity remained inconspicuous.
After the mountain had been completely wrapped in clouds all day on 22 January, the Monte Cagliato thermal camera showed a significant weakening of the lava flow on 23 January. This had previously been released from the effusive vent at the northeast base of New Southeast Crater in an easterly direction. Only some spots of the flow, which had previously stagnated at the base of the steep western wall of Valle del Bove, were still hot. Then, on the morning of 24 January, a new powerful thermal anomaly appeared just below the effusive vent. It was caused by a new gush of lava that poured eastwards again over the meanwhile cooling flow of the previous days. The new lava flow progressed slowly and on the morning of 25 January its front stagnated at the edge of the Valle del Bove, above the escarpment. Later, clouds moved in again and hid the mountain until the morning of 26 January. Through gaps in the clouds it was visible that the flow continued to stagnate and had even weakened somewhat compared to the previous day. In the evening of 26 January, the thermal anomalies below the effusive vent intensified and again a surge of fresh lava started moving eastwards. During the previous night, this flow then moved down the steep western wall of the Valle del Bove and reached about 2300 m high terrain in the morning. As the day progressed, however, the front stagnated again and this evening the lava flow did not look quite as well fed as yesterday.
At the summit craters, Bocca Nuova again showed the most gas emission last week, which was still frequently intensified in a pulse-like manner. Voragine and Northeast Crater continued to release only few amounts of gas. At the New Southeast Crater, gas was persistently emitted from the summit area. In the morning of 26 January, some brownish ash clouds mixed with the gas clouds from about 11:30. Around 14:45 I could see an even stronger ash emission there, which was nevertheless comparatively weak. The point of emission was apparently the upper northern summit area, which also generated some weak glow at times during the nights of the last weeks.
The volume of lava released since 27 November is calculated by INGV to be 3.7 - 4.8 million m3.
In the meantime, a sample of the current material, taken on 20 December 2022, was chemically analysed. It showed that the lava, with a CaO/Al2O3 ratio of 0.46 and an FeOtot/MgO ratio of 3.3, was more evolved than the lava emitted in 2022 during the paroxysmal phases of the Southeast Crater complex or during the May eruption. According to the INGV, this means that hardly any material was produced from greater depths [1].
The evaluation of the data from the GPS stations showed no significant changes for the period between 16 and 22 January [1].
The clinometric data showed no significant changes between 16 and 22 January [1].
The measurement of infrasound activity at the summit craters was massively disturbed by strong winds during the period 16 - 22 January and thus no data could be provided [1].
Sulphur dioxide emissions at the summit craters remained unchanged in the period between 16 and 22 January compared to the previous week and remained in the lower-medium range.
Soil carbon dioxide emissions (ETNAGAS station) held at medium levels between 16 and 22 January and were subject to a slight downward trend [1].
On the online seismograms of station ECNE, weak long-period signals as well as weak explosion signals were occasionally visible during the past week [2].
The tremor initially hovered on the border between low and medium levels last week, but then increased slightly and remained at lower-medium levels [2].
On 22.01., a quake of magnitude 1.6 was registered southeast of Monte Fontane (eastern flank). On 25.01., a quake of magnitude 1.7 occurred in the area of the summit craters [3].
My interpretation of the data and speculation about further development:
The analysis of the lava released in December showed that it was more evolved than the lava from the May 2022 eruption and significantly higher than the material emitted from New Southeast Crater during the paroxysmal phases in February 2022. This is also not surprising, because it was already largely degassed magma that generated practically no explosive activity, but flowed out very quietly. This magma had been stored in the mountain for some time and had time to evolve.
Unfortunately, there is no analysis (yet) of the lava currently being released. It is quite possible that it is somewhat more primitive than the December lava. However, as there is still no significant explosive activity, the proportion of more highly evolved and degassed magma still seems to be high. However, this could change in the near future and fresher magma could reach the surface.
Yesterday there were some ash emissions in the summit area of New Southeast Crater. It is possible that these were caused by deep-seated explosions, but smaller collapse events are more likely. However, if more fresh magma rises, the gases could cause strombolian explosions in the New Southeast Crater. Perhaps the ash emissions yesterday were already a first indication? Interesting is also the currently strongly fluctuating emission rate; a behaviour that has prevailed since mid-January and always causes new lava spurts. This could also be an indication that another, more gas-rich magma is now beginning to rise. But it could also mean that sufficient pressure can no longer build up to produce lava on a sustained basis. The temporary sinking and rising of the magma column under the New Southeast Crater could then also generate collapse events.
Thus, in my opinion, two developments are conceivable in the near future: 1. onset of strombolian explosions in the summit area of New Southeast Crater, with lava emission at the effusive vent remaining intensified in a push-like manner. 2. weakening or even end of the eruption and collapse events in the summit area or along the northern flank of New Southeast Crater associated with ash emissions.
In any case, Etna remains exciting!
1 - INGV-Sezione di Catania. 2023. Etna - BOLLETTINO SETTIMANALE - SETTIMANA DI RIFERIMENTO 16/01/2023 - 22/01/2023
2 - INGV-Sezione di Catania. 2023. Home. TREMORE VULCANICO. ECNE
3 - INGV. Osservatorio Etneo. Sorveglianza e Monitoraggio. DATABASE TERREMOTI. Localizzazioni di sala operativa. 2023.
Once again, I look back at an interesting stay on Mt Etna on #throwbackthursday. On the afternoon of 01 August 2012, I climbed the summit craters, where strombolian explosions had been occurring in the Bocca Nuova since the beginning of July. I stayed until nightfall and was able to take great photos of the activity.
Ice and ash, Mt Etna May 2009
Etna update, 20/01/2023
Last week, lava emission at the north-eastern base of Mt Etna's New Southeast Crater temporarily decreased. As a result, a new lava flow developed, which is now heading directly towards Valle del Bove.
On 14 January, the fronts of the lava tongues fed by the effusive vent at the northeastern base of New Southeast Crater stagnated at about 2200 - 2300 m altitude. During the evening, the associated thermal anomalies recorded by the Monte Cagliato thermal imaging camera weakened more and more. On 15 January, the lava flow was only active in the upper section, within the Valle del Leone. On 16 January, new small lava tongues were again working their way down the steep western slope of the Valle del Bove, but were no longer as well fed as in the previous weeks. On 17 January, only very small thermal anomalies were visible and it looked as if the lava emission had stopped completely. On the morning of 18 January, a new thermal anomaly appeared near the effusive vent. A new lava flow was now moving in an easterly direction, leaving the previously created lava field. By the evening of 19 January, the lava flow had continued on its easterly course, but progressed slowly despite the steepening terrain. This morning, its front stagnated at a roughly estimated altitude of about 2400 metres. Later, clouds moved in and hindered further observation.
Meanwhile, the summit craters continued their usual gas emissions during last week. They were strongest at Bocca Nuova and often pulsed. At New Southeast Crater, some gas was persistently emitted from the summit area. At Voragine and Bocca Nuova no gas emission was visible.
As INGV reports, the front of the most advanced lava flow was observed on 14 January at 2250 m elevation. By 14 January, a lava field with an area of 700,000 m2 had developed. The volume was calculated at 3.5 - 4.5 million m3 [1].
The analysis of the data from the GPS stations showed no significant changes for the period between 09 and 15 January [1].
The clinometric data did not show any significant changes in the Inclinations of the volcano between 09 and 15 January [1].
The measurement of infrasound activity at the summit craters was frequently disturbed by strong winds during the period 09 - 15 January. During the calm phases, activity similar to that of the previous week was recorded [1].
Sulphur dioxide emissions at the summit craters remained at the lower-medium level during the period 09-15 January.
Ground carbon dioxide emissions (station ETNAGAS) remained at a medium level between 09 and 15 January and were subject to only minor fluctuations.
The concentration of helium isotopes (3He/4He - ratio) in the Etna area, which was last determined on 09 January, was with a value of 0.63 similar to the last measurement in December. The value was thus still at a high level [1].
On the online seismograms of the ECNE station, weak explosion signals as well as individual long-period signals were regularly visible during the past week. From 18 January, there were also repeated phases of stronger noise that lasted only 1 - 3 minutes [2].
The tremor fluctuated between low and medium levels during the past week. The strongest decrease occurred on 17 January. Subsequently, the tremor increased again somewhat [2].
The source of the tremor was located between 09 and 15 January in the area below the central crater at an altitude between 1000 m and 2800 m [1].
My interpretation of the data and speculations about the further development:
The tremor was subject to some fluctuations in the last few days and the rate of lava production temporarily decreased significantly on 17 January. This could indicate that the supply of fresh magma to the effusive vent is gradually stalling. Presumably, not enough magma is rising at the moment or it has sought another path in the mountain along which it is migrating. Sulphur dioxide emissions from the summit craters have also been declining in recent weeks and there has been slight deflation of the volcanic edifice.
This suggests, in my opinion, that the current eruption may be slowly coming to an end. However, the still high Helium-3 concentration shows that fresh magma continues to rise under the mountain, which will be erupted sooner or later, at least in part. So it remains difficult to make a prognosis.
1 - INGV-Sezione di Catania. 2023. Etna - BOLLETTINO SETTIMANALE - SETTIMANA DI RIFERIMENTO 09/01/2023 - 15/01/2023
2 - INGV-Sezione di Catania. 2023. Home. TREMORE VULCANICO. ECNE
EtnaUpdater
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January 14, 2022, aerial reconnaissance photos by the Geological Survey of Tonga showing the eruption of a previously unremarkable submarine #volcano in the Pacific - the Hunga Tonga-Hunga Haʻapai 🌋 Nobody expected what would happen less than 24 hours later ... 💥
EtnaUpdater
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January 14, 1993, 6 volcanologists & 3 tourists are killed by an unexpected and sudden eruption at Galeras, Colombia. The survivors, severely injured, barely escaped the fury of the #volcano.
I have tried to introduce #VolcanoMonday here. Unfortunately, there has been no participation so far, but of course there aren't that many people here who have any photos at all.
Etna update, 13/01/2023:
Last week, lava emission continued at the effusive vent at the northeast base of Mt Etna's New Southeast Crater. Different partial flows continued to be fed, moving through a system of tunnels and channels to the rim of the Valle del Bove. There, the fronts of two or three lava flows stagnated at about 2100 m above Monte Simone. From 08 January, the tongues retreated. Bad weather with fresh snow hampered observations until 10 January. From 11 January visibility was very good again and the hot, fan-shaped lava field stood out very well as a dark area on the snow-covered mountain. During the day, the fronts of the lava tongues descended again a little further down the slope and reached about 2200 m high terrain.
On 12 January, the southernmost lava tongue advanced even further down the slope, but then stagnated today at about 2100 - 2200 m high terrain.
Meanwhile, the usual gas emissions continued at the summit craters of Etna, which were still strongest at Bocca Nuova. During the nights, however, I could no longer observe any glow there. On the other hand, from 11 January onwards, some glow appeared on light sensible webcams in the upper northern summit area of New Southeast Crater. This was probably caused by rising heat or high-temperature fumaroles.
As reported by INGV, the front of the most advanced lava flow reached 2170 m high terrain between 04 and 07 January. The average production rate could be estimated at about 3 m3 lava/s with the help of satellite data. On 07 January, the volume of lava produced since the beginning of the eruption on 27.11.2022 was calculated to be about 2.5 - 4.3 million m3 [1].
The evaluation of the data from the GPS stations showed no significant changes between 02 and 08 January. However, the slight trend towards deflation of the volcanic edifice continued [1].
The clinometric data showed no significant changes in the slopes of the volcano between 02 and 08 January [1].
The infrasound activity at the summit craters was characterised by a relatively high frequency of events in the period from 02 - 08 January. However, the amplitude was low, indicating weak to moderate activity. The source of the events was Bocca Nuova [1].
The sulphur dioxide emissions at the summit craters decreased slightly in the period between 02 and 08 January compared to the previous week and were in the lower medium level.
Ground carbon dioxide emissions (station ETNAGAS) remained at a medium level between 02 and 08 January and were subject to only minor fluctuations [1].
The online seismograms of station ECNE showed occasional weak explosion signals or long-period signals during the past week.
The tremor was initially still on the border between low and medium levels last week, but then rose again somewhat from 10 January and has been slowly decreasing since then [2].
Until 05 January, the source of the tremor was located at an altitude of 2700 - 2900 m in the area between Southeast Crater and the effusive vent. From 05 January on a shift to the area northwest of Southeast Crater at an altitude of 2300 - 2700 m was detected [1].
On 07.01. a quake of magnitude 1.5 was recorded in the area of Grotta del Gelo (northern flank). On 12.01., two earthquakes with magnitudes of 2.3 and 1.9 were recorded near Biancavilla (southern flank) [3].
1 - INGV-Sezione di Catania. 2023. Etna - BOLLETTINO SETTIMANALE - SETTIMANA DI RIFERIMENTO 02/01/2023 - 08/01/2023
2 -INGV-Sezione di Catania. 2023. Home. TREMORE VULCANICO. ECNE
3 - INGV. Osservatorio Etneo. Sorveglianza e Monitoraggio. DATABASE TERREMOTI. Localizzazioni di sala operativa. 2023.
Etna update, 06/01/2023:
During the past week, lava production continued at the northeast base of Mt Etna's New Southeast Crater. The lava continued to move in the form of several partial flows through the Valle del Leone to the edge of the Valle del Bove. On the steepening terrain, new tongues developed again and again. Sometimes a more southern and sometimes a more northern tongue was fed. As a result, the fronts of the tongues did not advance far and stagnated at about 2200 m high terrain in the area southwest to west of Monte Simone.
During 03 January, the intensity of the thermal anomalies visible from the active lava tongues in the Monte Cagliato thermal imager photos weakened considerably. By the evening, only the upper section of the lava field was active. In the afternoon of 04 January, the thermal anomalies in the area of the effusive vent intensified and some time later the lava tongues at the edge of the Valle del Bove became active again. Until the morning of 05 January, they again moved down the steep terrain, but initially did not advance further than about 2300 - 2200 m altitude.
By the evening of 05 January, the lava flow intensified and, especially in the southern section of the lava field, a lava tongue became more and more intense. In the early morning of 06 January, its front reached the valley floor of the Valle del Bove at about 2000 m altitude. At the same time, a little further north, another tongue made better progress than in previous weeks and moved towards the valley floor.
On the evening of 02 January, light sensitive webcams showed pulsating glow over Bocca Nuova. However, I could not observe any thermal anomalies. Probably deep-seated strombolian explosions started in one of the vents of Bocca Nuova. Also during the following nights, faint glow was visible above Bocca Nuova. On the evening of 05 January, the gas clouds above the summit crater were only sporadically illuminated, but in the early morning of 06 January, the glow became more frequent again.
The analysis of the data from the GPS stations showed no significant changes between 26 December and 01 January. However, a reversal of the trend towards inflation was observed during the past month and measurements between the Pizzi Deneri (EPDN), Cratere del Piano (ECPN) and Punta Lucia (EPLU) stations revealed a slight deflation of the volcanic edifice [1].
Clinometric data showed no significant changes between 26 December and 01 January [1].
Infrasound activity at the summit craters remained low during the period from 26 Dec to 01 Jan, but measurements were affected by wind. The source of the activity was Bocca Nuova [1].
Sulphur dioxide emissions at the summit craters hardly changed in the period between 26 December and 01 January compared to the previous week and remained at medium levels.
Ground carbon dioxide emissions (ETNAGAS station) remained at a medium level between 26 December and 01 January [1].
The online seismograms of station ECNE were initially still overlaid by noise caused by the persistently increased tremor. After the tremor decreased, weak explosion signals were occasionally visible from 05 January onwards [2].
In the past week, the tremor was initially still at a medium level and was subject to only minor fluctuations. From 05 January, it decreased significantly and reached a low level [2].
Between 26 December and 01 January, the source of the tremor was in the area of the Southeast Crater at an altitude between 2700 and 2900 m [1].
On 01.01., two earthquakes occurred in the area north of Ragalna (southern flank), reaching magnitudes of 2.0 and 2.8 [3].
My interpretation of the data and speculations about the further development:
It was interesting in the past few days that sporadic glow appeared again over Bocca Nuova after a long time. This was last the case in September last year. Presumably, deep-seated strombolian explosions are occurring there again now. It is also interesting that the tremor decreased significantly on 05 January, but this did not affect the lava production at the effusive vent. On the contrary, as the fronts of the lava eruptions have advanced today as never before during the current eruption, the production rate has apparently increased.
Since weak deflation has been measured at the volcanic edifice in recent weeks, more lava is probably currently being produced than is rising from under the mountain. If this continues, the end of the eruption could soon be in sight. However, there still seems to be plenty of fresh magma acummulating under the mountain, because the ratio of helium isotopes had reached high levels again in the last measurement in mid-December. Thus, it remains difficult to predict how the current eruption will continue.
1 - INGV-Sezione di Catania. 2023. Etna - BOLLETTINO SETTIMANALE - SETTIMANA DI RIFERIMENTO 26/12/2022 - 01/01/2023
2 -INGV-Sezione di Catania. 2023. Home. TREMORE VULCANICO. ECNE
3 - INGV. Osservatorio Etneo. Sorveglianza e Monitoraggio. DATABASE TERREMOTI. Localizzazioni di sala operativa. 2023.
A recent and impressive video of the effusive activity on Mt Etna from etna walk:
EtnaUpdater
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EtnaUpdater
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How beautiful is this? #Etna continues emitting lava, which has been growing into a vast lava field with multiple active lobes reaching a length of more than 1.5 km and a volume estimated at about 1.5-2 million cubic meters. These two photos were taken at nightfall on 2 January 2023 from the northern crest of the Valle del Bove, on the northeast flank of the volcano.
Today, once again a photo for #VolcanoMonday :
It shows the 3432 m high Irazu in Costa Rica. It contains an acid lake and is considered one of the most dangerous volcanoes in the country. It is one of Costa Rica's "drive in volcanoes", as a well-built road leads up to its summit. I took the photo in March 2007.
EtnaUpdater
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Last sunset of 2022 watching #Etna's current lava flow with my wife Catherine from a panoramic point on the east flank of the volcano, Monte Fontane. This lava flow has been slowly growing since it started on 27 November 2022.
EtnaUpdater
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L’evoluzione geomorfologica del vulcano Etna dal 1983 al 2021 🌋
📷 IntraGeo
#etna #vulcano #evoluzione
Etna update, 30/12/2022:
During the past week, effusive activity continued at the northeastern base of the New Southeast Crater. Several partial flows poured over the fan-shaped lava field in a northeasterly direction, crossed the Valle del Leone and reached the edge of the Valle del Bove. There they moved as several tongues in an easterly direction down the steep slope and formed an ever-widening lava field. The fronts of the tongues stagnated at 2100 - 2300 m altitude in the area southwest of Monte Simone.
Furthermore, I could not observe any explosive activity in the area of the effusive vents or in the summit area of New Southeast Crater.
At Bocca Nuova, pulsating gas emission continued. No significant gas emission was visible at Voragine and Northeast Crater.
As INGV reports, the front of the lava flow reached 2150 m high terrain on 25 December. Using MODIS/VIIRS satellite data, the volume of lava released so far could be estimated at 1,200,000 - 2,400,000 m3. The data also show that the production rate has increased from about 20 December, rising from about 1 m3/s initially to about 2 - 2.5 m3/s [1].
Analysis of the data from the GPS stations showed no significant changes between 19 and 25 December [1].
The clinometric data showed no significant changes between 19 and 25 December [1].
Infrasound activity at the summit craters was low during the period from 19 to 25 December. The source of the activity was Bocca Nuova [1].
Sulphur dioxide emissions at the summit craters decreased in the period between 19 and 25 December and reached medium levels.
Ground carbon dioxide emissions (ETNAGAS station) remained at a medium level between 19 and 25 December.
The concentration of helium isotopes (3He/4He - ratio) in the Etna area, which was last determined on 15 December, was higher than in the last measurements with a value of 0.64. High levels have now been reached again [1].
The online seismograms of station ECNE continued to be overlaid by noise caused by the persistently elevated tremor last week [2].
The tremor decreased somewhat on 24 December, but continued to hover at medium levels [2].
The source of the tremor between 19 and 25 December was in the area between Southeast Crater and Bocca Nuova at an altitude between 2500 and 2800 m [1].
On 23.12. a quake with a magnitude of 1.6 occurred in the area southeast of Case del Vescovo (southeast flank). On 23.12. a quake with a magnitude of 1.8 was measured on Monte Scorsone (east flank). On 25.12., a quake of magnitude 1.6 occurred southeast of Fiumefreddo di Sicilia (eastern flank) [3].
1 - INGV-Sezione di Catania. 2022. Etna - BOLLETTINO SETTIMANALE - SETTIMANA DI RIFERIMENTO 19/12/2022 - 25/12/2022
2 - INGV-Sezione di Catania. 2022. Home. TREMORE VULCANICO. ECNE
3 - INGV. Osservatorio Etneo. Sorveglianza e Monitoraggio. DATABASE TERREMOTI. Localizzazioni di sala operativa. 2022.
Photo by INGV
Volcanophilic nerd & #volcano hiker blogging about Mt #Etna since 2004. Find tweets about Etna and also my backyard geology, the #Vogelsberg area.
Joined Nov 2022
