Intense gas-and-steam plumes rose above the volcano several times during 6-11 October, with the highest plume climbing 500 m. During the report period, weak fumarolic activity occurred and seismicity was at background levels. Satellite imagery on 2 October showed a broad band of warm ground that appeared to follow the rim of the crater, with a small area of warm ground in the center of the crater. The volcano remained at Concern Color Code Yellow.

Geological Summary. Avachinsky, one of Kamchatka's most active volcanoes, rises above Petropavlovsk, Kamchatka's largest city. It began to form during the middle or late Pleistocene, and is flanked to the SE by Kozelsky volcano, which has a large crater breached to the NE. A large collapse scarp open to the SW was created when a major debris avalanche about 30,000-40,000 years ago buried an area of about 500 km2 to the south, underlying the city of Petropavlovsk. Reconstruction of the volcano took place in two stages, the first of which began about 18,000 years before present (BP), and the second 7,000 years BP. Most eruptions have been explosive, with pyroclastic flows and hot lahars being directed primarily to the SW by the collapse scarp, although there have also been relatively short lava flows. The frequent historical eruptions have been similar in style and magnitude to previous Holocene eruptions.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)