This paper considers the propagation of ash during the paroxysmal eruption of Sheveluch Volcano which occurred April 10–13, 2023, and its impact on the water resources of the affected area. We characterize ash thicknesses at various population centers and describe the grain-size composition of the ash. We show that the propagation of ash plumes is primarily driven by the eruption dynamics, but atmospheric circulation actually controls the spatial distribution of deposit thickness. The water-soluble salts contained in the ash and the dynamics of their washing out under natural conditions have been determined. The water-soluble part of fresh ash is dominated by calcium and magnesium sulfates, sodium chloride, with minor amounts of chlorides and fluorides of aluminum, potassium, and ammonium. The first substances to be washed out from ashes are well-soluble chlorides, to be followed by sulfates. As time goes on, the total concentration of soluble salts is decreasing, and their qualitative composition changes: hydrogen carbonates of calcium, magnesium, and sodium begin to dominate. Several months after the eruption, the impact of the ashfall on water resources of the settlements, including open springs at the ground surface, was leveled out.

Sheveluch is one of the most active volcanoes in Kamchatka. Its modern edifice includes three main elements: Old Sheveluch, an ancient caldera and Young Sheveluch. On the southeastern slope of Old Sheveluch, there is a group of ancient extrusive domes (from south to north): Sherokhovataya, Krasnaya, Karan, and Sopochka na sklone. Only in the area of the Karan dome are there heated areas with mofets temperature of 70–96°C. After the powerful explosive eruption of the Sheveluch volcano in April 2023, the gas–steam activity of the Karan dome intensified, and a thermal anomaly began to be noted in satellite images of the area of this dome. On April 26, 2024, in a JPSS-1 satellite image at 15:07 UTC, Kamchatkan Volcanic Eruption Response Team scientists discovered a bright thermal anomaly in the area of the Karan dome; that is, they recorded a unique phenomenon on this day: the birth of a new volcanogenic formation – the new lava dome. It was given the name 300 years of the Russian Academy of Sciences. As of June 7, 2024, the size of the new dome was 800 × 500 m and the area of the dome crown was 0.19 km2. The eruption of the new lava dome 300 Years of the Russian Academy of Sciences is continuing.

This paper presents the results from a study of ash compositions that were erupted in 2013–2016.
The juvenile component has been identified in the ejecta using data on the morphology and textural features of ash particles and the composition of volcanic glasses. The data set suggests that the activity of the volcano was phreatomagmatic.

The Sheveluch volcano is the northernmost active volcano in Kamchatka. In this work, we describe the activity of the new 300 Years of the RAS lava dome of volcano in 2024–2025. Explosive eruptions of the dome were observed on August 17–18, September 1–2, and November 7–10, 2024: eruptive columns rose up to 9, 8, and 11 km above sea level, respectively, and ash plumes were extended for 2400, 1100, and 3000 km to the east and northeast of the volcano. The results of detailed real-time monitoring of the volcanic eruption are presented using a video surveillance system and various satellite data from The Remote Monitoring of Volcanic Activity in Kamchatka and the Kurile Islands information system (VolSatView, http://kamchatka.volcanoes.smislab.ru).