April 27 , 2021 .
Italy / Sicily , Etna :
Press release on ETNA’s activity, April 26, 2021, 21:52 (19:52 UTC).
The National Institute of Geophysics and Volcanology, Osservatorio Etneo, reports that from around 6.30 p.m. there is a weak resumption of Strombolian activity at the Southeast Crater. In addition, still at the Southeast Crater, unique episodes of impulsive explosions with moderate emission of ash, which quickly dispersed in the atmosphere, were recorded today.
We almost got used to this silent volcano, exhausted after this insane streak of paroxysmal episodes between February 16 and April 1 (and all the activity leading up to it for the past two years). I must admit that this truce did not bother me, finally I could – and so many colleagues – take back some things which remain motionless for a long time.
Of course, the show was a bit lacking. It was like a dream, these huge lava fountains, the eruptive columns that seemed to want to hold the sky. As always after a series of lava fountains, a bit like after the first kiss: ′ ′ But is it true? Did I really experience it? «
But Etna wouldn’t be among the most active volcanoes in the world if it didn’t give new signs of life soon, and here they are, those signs of life. After two strong explosions on the night of April 24-25 and the morning of April 26 at the Southeast Crater, we saw red in the evening, small Strombolian explosions from the eastern mouth of the Southeast. Everything is very modest, very hesitant, almost as if he didn’t dare come back on stage.
We don’t have the means to say if this activity will continue, how it will evolve, if it is the beginning of a new story or the continuation of the old one. There is currently no seismic activity on Etna, the soil deformations are extremely reduced compared to what we have seen between the ′ ′ ′ ′ ′ ′ of the fall-winter and the ′ ′ deflation ′ ′ from February-March.
From a seismic point of view, the average amplitude of the volcanic tremor shows an upward trend, currently focusing on medium-low values. The location of the source of the tremor is near the Southeast Crater area at an altitude of 2,500 m above sea level.
Regarding infrasound activity, it remains at medium-low levels, with events localized in the area of the Southeast Crater.
The strain data does not show significant changes.
Further updates will be communicated shortly.
Source : INGV.
Photo et commentaire : Boris Behncke.
Peru , Sabancaya :
Analysis period: from April 19, 2021 to April 25, 2021, Arequipa, April 26, 2021.
Alert level: ORANGE
The Geophysical Institute of Peru (IGP) reports that the eruptive activity of the Sabancaya volcano remains at moderate levels, that is, with the recording of an average of 90 daily explosions, with columns of ash and gas up to 2 km altitude above the summit of the volcano and their consequent dispersion. Therefore, for the following days, no significant change is expected in eruptive activity.
The IGP recorded and analyzed the occurrence of 1659 earthquakes of volcanic origin, associated with the circulation of magmatic fluids inside the Sabancaya volcano. An average of 90 explosions was recorded daily. During this period, Volcano-Tectonic (VT) earthquakes associated with rock fractures were located mainly in the North-West and North-East of Sabancaya.
The monitoring of the deformation of the volcanic structure using GNSS techniques (processed with fast orbits) does not present any significant anomalies. However, in general, an inflation process was observed in the northern sector (around the Hualca Hualca volcano). Visual surveillance identified columns of gas and ash up to 2 km altitude above the summit of the volcano, which were scattered towards the eastern, southeast, and southern sectors of Sabancaya. Satellite recordings have identified the presence of 11 thermal anomalies (maximum value of 32 MW) associated with the presence of a lava body on the surface of the volcano’s crater. Finally, in the northeast sector of the crater, a zone of vents and orifices was observed through which, possibly, a low volume lava flow was emitted.
RECOMMENDATIONS
• Keep the volcanic alert level in orange.
• Do not approach within a radius of less than 12 km from the crater.
Source et photo : IGP.
Saint Vincent , Soufrière Saint Vincent :
La Soufrière, St. Vincent SCIENTIFIC UPDATE – 26/04/21 6:00PM
– Seismic activity at La Soufrière, St Vincent has been low after the tremor associated with the explosion and ash venting around noon on 22 April.
– Only a few long-period, hybrid and volcano-tectonic earthquakes were recorded and there was no further tremor.
– An observation flight took place today in a fixed-wing aircraft at about 11:30 am. Visibility was poor, with clouds blocking the crater for much of the time.
– White steam could be seen venting near-continuously from several locations on the crater floor. No dome was visible, although a spine could be seen through the clouds.
-The volcano continues to erupt. Its pattern of seismic activity over the last few days is typical of the growth and destruction of lava domes. Explosions with accompanying ashfall, of similar or larger magnitude, can restart with little or no warning.
– The volcano is at alert level Red.
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Source : UWI.
Indonesia , Sinabung :
The activity level has been at level III (SIAGA) since May 20, 2019 at 10:00 a.m. WIB. Mount Api Sinabung (2460 m above sea level) has been erupting since 2013. The last eruption occurred on April 13, 2021 with a maximum column height of 500 to 1600 meters above the summit.
The volcano is clearly visible until it is covered in fog. The crater emits white smoke with a moderate height, thick, about 50-700 meters above the summit. The weather is sunny to rainy, with weak to moderate winds to the east and south-east.
According to the seismographs of April 26, 2021, it was recorded:
2 eruption / explosion earthquakes
64 avalanche earthquake
18 earthquakes of emissions
11 low frequency earthquakes
47 hybrid / multi-phase earthquakes
1 deep volcanic earthquake
6 local tectonic earthquakes
1 distant tectonic earthquakes.
VOLCANO OBSERVATORY NOTICE FOR AVIATION – VONA.
Issued : April 27 , 2021.
Volcano : Sinabung (261080)
Current Aviation Colour Code : ORANGE
Previous Aviation Colour Code : orange
Source : Sinabung Volcano Observatory
Notice Number : 2021SIN57
Volcano Location : N 03 deg 10 min 12 sec E 98 deg 23 min 31 sec
Area : North Sumatra, Indonesia
Summit Elevation : 7872 FT (2460 M)
Volcanic Activity Summary :
Eruption with volcanic ash cloud at 03h23 UTC (10h23 local)
Volcanic Cloud Height :
Best estimate of ash-cloud top is around 11072 FT (3460 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer.
Other Volcanic Cloud Information :
Ash-cloud moving to E-SE.
Remarks :
Seismic activity is characterized by eruption
Source : PVMBG.
Photo : Nachelle homestay.