KVERT reported that during 1-8 June, seismic activity at Kliuchevskoi continued above background levels and a thermal anomaly in the crater was detected on satellite imagery. Video and visual observations during 1-4 June indicated Strombolian and Vulcanian eruptions at the summit crater. Lava flows generated phreatic bursts from places where hot lava interacted with ice on the NW and SE flanks. Ash plumes rose to altitudes of 7 km (23,000 ft) a.s.l. and drifted E and SE during 1-6 June. Plumes were seen on satellite imagery drifting E and S during 1-8 June. Based on information from KVERT, the Tokyo VAAC reported that an ash plume rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted NW on 12 June. The Level of Concern Color Code remained at Orange.

Geological Summary. Klyuchevskoy (also spelled Kliuchevskoi) is Kamchatka's highest and most active volcano. Since its origin about 6000 years ago, the beautifully symmetrical, 4835-m-high basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. It rises above a saddle NE of sharp-peaked Kamen volcano and lies SE of the broad Ushkovsky massif. More than 100 flank eruptions have occurred during the past roughly 3000 years, with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks of the conical volcano between 500 m and 3600 m elevation. The morphology of the 700-m-wide summit crater has been frequently modified by historical eruptions, which have been recorded since the late-17th century. Historical eruptions have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters.

Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), Tokyo Volcanic Ash Advisory Center (VAAC)