During 11-18 February, seismicity was above background levels at Kliuchevskoi, with a large number of shallow earthquakes occurring daily. Ash plumes rose ~3 km above the volcano's crater during 12-14 February. Phreatic bursts, which occurred when lava flows contacted a glacier, were seen on 12 and 13 February. During 12-16 February, volcanic bombs were hurled 300-500 m above the crater, Strombolian activity occurred in the crater, and lava traveled into Krestovsky channel on the volcano's NW flank. During a flight on 16 February, a mudflow was seen extending 27 km. According to a news report, a lava flow from Kliuchevskoi melted a large section of Ehrman glacier. Kliuchevskoi remained at Concern Color Code 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.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)