Report on Avachinsky (Russia) — October 1993
Bulletin of the Global Volcanism Network, vol. 18, no. 10 (October 1993)
Managing Editor: Edward Venzke.
Avachinsky (Russia) Usual fumarolic activity; seismicity low
Please cite this report as:
Global Volcanism Program, 1993. Report on Avachinsky (Russia) (Venzke, E., ed.). Bulletin of the Global Volcanism Network, 18:10. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199310-300100
53.256°N, 158.836°E; summit elev. 2717 m
All times are local (unless otherwise noted)
Helicopter observations on 12-13 September revealed only the usual fumarolic activity, which was continuing through 6 November. Seismicity also remained at background levels of ~2-3 earthquakes/day through 28 October, except for an increase to ~8-10 earthquakes/day at depths of 1-2 km during the week of 14-21 October.
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.
Information Contacts: V. Kirianov, IVGG.