At Sakurajima, at the summit crater of Minamidake, nine eruptions occurred, including two explosions, according to the JMA on April 27. The plume rose up to 2500m above the edge of the crater before dispersing east.
The largest volcanic blocks reach the 6th station (800 to 1100 m from the Minamidake summit crater).
Inclinometers and extensometers installed on the island show the uplift and the expansion of the volcano.
Source: JMA / Fukuoka District Weather Observatory, Kagoshima Local Weather Observatory / info # 35.
In Suwanosjima, in the Ryukyu arc, an eruptive episode is reported on April 28 at 4:17 am; it was accompanied by a plume at 1,400 meters above the crater, with a flow towards the south-east.
The activity is in progress, and the alert levels unchanged.
The Peruvian Geophysical Institute (IGP) reports that the eruptive activity of the Sabancaya volcano remains at moderate levels; that is to say with the continuous record of explosions with columns up to 2 km high above the summit of the volcano and the consequent emission of ash and gas. Consequently, for the following days, no significant change is expected regarding its activity.
Between 20 and 26 April 2020, the IGP recorded and analyzed the occurrence of around 297 earthquakes of volcanic origin, associated with the circulation of fluids (magma, gas, etc.) inside the volcano.
On average, 9 daily explosions of low to medium intensity were recorded. Plumes of gas and ash up to 2 km high above the summit of the volcano could be observed, scattered towards the southwest, south and southeast sectors of the Sabancaya.
Between April 21 and 25, major earthquakes were recorded in the Colca Valley region, with magnitudes between M3.2 and M4.1, associated with tectonic and volcanic activity; The epicenters of these earthquakes are located within a radius of 20 km around the crater of the volcano.
The monitoring of the deformation of the volcanic structure, using GNSS data (processed with fast orbits), does not present any significant anomalies; However, the presence of slight inflation in the area of the northern Sabancaya volcano (near the Hualca Hualca volcano) has been observed.
Satellite surveillance has enabled the presence of 8 thermal anomalies with values between 3 MW and 15 MW, associated with the presence of a body of lava (dome) on the surface of the crater of the volcano.
The volcanic alert level remains orange, with an exclusion zone of 12 km radius around the crater.
Source: I.G. Peru & Cenvul
The Anak Krakatau, on alert 2 / waspada, presented thermal anomalies between medium and low on April 26; visible on April 27 on a Sentinel-2 satellite image, it was not signaled by Mirova, due to cloud cover.
The PVMBG signals at the seismicity level for April 27 :
- 13 blast earthquakes, with an amplitude of 3-20 mm, and an earthquake duration of 6-28 seconds.
- 37 low frequency earthquakes with an amplitude of 2 to 9 mm and an earthquake duration of 3 to 10 seconds.
- 4 hybrid earthquakes with an amplitude of 7 to 9 mm, the S-P was not observed and the earthquake and for 5 to 10 seconds.
- 4 shallow volcanic earthquakes, with an amplitude of 2 to 6 mm, for 4 to 8 seconds.
- 4 episodes of continuous tremor with an amplitude of 0.5 to 6 mm, dominating 1 mm.
The public / tourists are not allowed to approach the crater within 2 km of the crater.
Sources: PVMBG, Magma Indonesia, Mirove and Sentinel-2
Stromboli - hot spots on the terrace and bluish plume of gas on 04.27.2020 - Sentinel-2 L1C image bands 12,11,4 - one click to enlarge
Bonus: a beautiful bluish plume of gas at Stromboli on 04.27.2020