KVERT reported that during 26 October-2 November moderate seismic activity at Kizimen was detected along with a thermal anomaly in satellite imagery. Video and satellite images showed lava flows effusing from the summit and the E flank, summit incandescence, strong gas-and-steam activity, and hot avalanches on the S flank. The Aviation Color Code was raised to Orange on 1 November. Based on information from the Kamchatka Branch of Geophysical Services (KGBS), the Tokyo VAAC reported that an ash plume drifted NE at an altitude of 5.2 km (17,000 ft) a.s.l. on 2 November. KVERT reported that during 2-3 November moderate seismicity indicated that possible ash plumes rose to altitudes of 4.5-4.8 km (14,800-15,800 ft) a.s.l. Video images showed gas-and-steam activity during 2-5 November. Incandescence above the crater and lava flow were observed on 5 November.

Geological Summary. Kizimen is an isolated, conical stratovolcano that is morphologically similar to St. Helens prior to its 1980 eruption. The summit consists of overlapping lava domes, and blocky lava flows descend the flanks of the volcano, which is the westernmost of a volcanic chain north of Kronotsky volcano. The 2334-m-high edifice was formed during four eruptive cycles beginning about 12,000 years ago and lasting 2000-3500 years. The largest eruptions took place about 10,000 and 8300-8400 years ago, and three periods of long-term lava dome growth have occurred. The latest eruptive cycle began about 3000 years ago with a large explosion and was followed by intermittent lava dome growth lasting about 1000 years. An explosive eruption about 1100 years ago produced a lateral blast and created a 1.0 x 0.7 km wide crater breached to the NE, inside which a small lava dome (the fourth at Kizimen) has grown. Prior to 2010, only a single explosive eruption, during 1927-28, had been recorded in historical time.

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