Activity of Kavachi, Klyuchevskoy and Semeru.

The ongoing eruption of the Kavachi submarine volcano is visible under clouds in a Sentinel hub / CopernicusEU image from September 2, 2022.

The roughly conical edifice rises to water depths of 1.1 to 1.2 km to the north and to greater depths to the SE. Frequent shallow submarine and occasional subaerial eruptions produce phreatomagmatic explosions that eject steam, ash and glowing bombs.

It has been erupting since October 2, 2021, and ongoing (GVP).

Sources: Sentinel-2 & Global Volcanism Program

The Klyuchevskoy volcano is quiet.

A strong wind lifts the ashes from the eastern slope of the volcano; a plume of resuspended ash extends 180 km east of the volcano.

An ash advisory has been issued by VAAC Tokyo.

Sources: KVERT & VAAC Tokyo

The Semeru volcano is not very visible on September 4, covered with fog 0-II to covered with fog 0-III. Smoke from the crater was not observed.

Seismicity is characterized by:
- 88 eruption earthquakes, with an amplitude of 10-23 mm and an earthquake duration of 40-159 seconds.
- 3 emission earthquakes, with an amplitude of 3 to 7 mm and the duration of the earthquake was 30 to 50 seconds.
- 1 deep volcanic earthquake, with an amplitude of 6 mm, S-P 2 seconds and an earthquake duration of 15 seconds.
- 1 local tectonic earthquake, with an amplitude of 12 mm, S-P 9 seconds and an earthquake duration of 30 seconds.
- 1 distant tectonic earthquake.

The activity level remains at 3 / Siaga, with recommendations:
- to carry out no activity in the southeastern sector along Besuk Kobokan, up to 13 km from the summit (the center of the eruption). Outside of this distance, the community does not conduct activities within 500 meters of the bank (river edge) along Besuk Kobokan due to the potential for expansion from hot clouds and lava flows. at a distance of 17 km from the summit.
- not to travel within 5 km of the crater/summit of Mount Semeru as it is subject to the danger of thrown (incandescent) blocks.

Source: PVMBG, Magma Indonesia