KVERT reported that seismic activity from Karymsky was above background levels during 15-22 October, suggesting that possible ash plumes rose to altitudes of 2-4 km (6,600-13,100 ft) a.s.l. Volcanologists working at Karymsky observed Strombolian activity at night, along with ash plumes during 14-16 October that rose to altitudes of 2.5-3 km (8,200-10,000 ft) a.s.l. and drifted E. A thermal anomaly was seen in satellite imagery during 15-16 and 18-19 October. The Aviation Color Code level remained at Orange.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Geological Summary. Karymsky is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the S side of the Pleistocene Dvor volcano and is located outside the N margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, located immediately south. The enclosing caldera formed about 7,600-7,700 radiocarbon years ago; construction of the stratovolcano began about 2,000 years later. The latest eruptive period began about 500 years ago, following a 2,300 years of quiescence. Much of the cone is covered by lava flows less than 200 years old. Recorded eruptions have been Vulcanian or Vulcanian-Strombolian with moderate explosive activity and occasional lava flows from the summit crater.