KVERT reported that at 1235 on 17 November an ash plume from Kliuchevskoi, detected in satellite images, rose to an altitude of 6.5 km (19,700 ft) a.s.l. and drifted 160 km NE. At 1322 an ash plume rose to an altitude of 7km (23,000 ft) a.s.l. and drifted 130 km NE. Video data then showed a high-intensity explosion and Strombolian activity prompting KVERT to raise the Aviation Color Code to Orange.

At 1416 on 19 November seismicity indicated a strong explosion, and observers reported that ash plumes rose to altitudes of 10-12 km (32,800-39,400 ft) a.s.l. and drifted SE. The Aviation Color Code was raised to Red. Later that day the altitudes of the ash plumes were lower; video images showed ash plumes rising to altitudes of 5-5.5 km(16,400-18,000 ft) a.s.l. and drifting NE. The Aviation Color Code was lowered to 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)