The Kamchatka Volcanological Station reported that seismicity at Sheveluch began increasing on 24 April. According to KVERT a new lava dome, named Karan-1, began to grow on the SW flank at around 0200 local time on 27 April based on the intensification of thermal anomalies detected in satellite observations. During 27 April-3 May intense steam-and-gas emissions rose from the active area and on 28 April an ash plume drifted about 25 km NW. Kamchatka Volcanological Station noted that an ash plume rose 2 km on 30 April. Lava-dome incandescence was occasionally visible during the week in webcam images and a daily intense thermal anomaly over the dome complex was identified in satellite images. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.

Geological Summary. The high, isolated massif of Sheveluch volcano (also spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group. The 1,300 km3 andesitic volcano is one of Kamchatka's largest and most active volcanic structures, with at least 60 large eruptions during the Holocene. The summit of roughly 65,000-year-old Stary Shiveluch is truncated by a broad 9-km-wide late-Pleistocene caldera breached to the south. Many lava domes occur on its outer flanks. The Molodoy Shiveluch lava dome complex was constructed during the Holocene within the large open caldera; Holocene lava dome extrusion also took place on the flanks of Stary Shiveluch. Widespread tephra layers from these eruptions have provided valuable time markers for dating volcanic events in Kamchatka. Frequent collapses of dome complexes, most recently in 1964, have produced debris avalanches whose deposits cover much of the floor of the breached caldera.

Sources: Kamchatka Volcanological Station, Kamchatkan Volcanic Eruption Response Team (KVERT)