KVERT reported that during 7-13 January a thermal anomaly over Kizimen was observed in satellite imagery. Pyroclastic flow deposits on the E flank were noted. Seismicity, recorded during 6-7 and 12 January, was high but variable, and many shallow volcanic earthquakes as well as volcanic tremor continued to be detected. Ash plumes that rose to altitudes of 6-8 km (20,000-26,000 ft) a.s.l. during 5-13 January were visually observed drifting multiple directions, and seen in satellite imagery more than 275 km W and NW. On 12 January ashfall was reported in the villages of Anavgai and Esso, 140 km NW. Seismic data during 14-15 January suggested that ash plumes rose to altitudes of 4-5 km (13,100-16,400 ft) a.s.l. Satellite images showed a bright thermal anomaly over the volcano and ash plumes drifting more than 180 km W on 15 January. The Aviation Color Code level was lowered to Orange.

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