Russian Avachinsky volcano, located close to Kamchatka's largest city - Petropavlovsk (population 180 000) is showing signs of increased unrest over the past couple of days, with notable incandescence, degassing and elevated seismicity.
A gradual increase in seismic energy released in the volcanic structure has been observed for about a month, said Danila Chebrov, chairman of the Kamchatka branch of the Unified Geophysical Service of the Russian Academy of Sciences (KB REC). "The energy class of individual earthquakes exceeds 5. For this volcano, these are significant events."
"We cannot say that Avacha will certainly erupt in the next month, but such a scenario is now very likely - be careful," Chebrov sad.
Authorities are warning locals and tourists to stay away from the volcano. Climbing the volcano as well as being within a radius of 5 km (3.1 miles) is not recommended.
Volcano warning for city of Petropavlovsk-Kamchatsky amid ‘very likely’ eruption. City of 180,000 is just 26 km from ‘waking’ Avachinsky on Pacific’s ring of firehttps://t.co/s4xwdMzt5e pic.twitter.com/5pqkVWVShy— The Siberian Times (@siberian_times) December 9, 2019
#volcan #volcano #Avachinsky Ce système volcanique semble un peu instable ces temps-ci:dégazage à très haute T° actuellement & un peu de sismicité semble-t-il/This volcanic system seems relatively unstable actually:very high T° gaz release & some sismicity https://t.co/OZy9A5FsBK pic.twitter.com/EMErkNdcwv— CultureVolcan (@CultureVolcan) December 10, 2019
The last known eruption of this volcano took place on October 5, 2019 (VEI 1). Its previous eruptions were recorded from January 13 - 30, 1991 (VEI 2), February 25, 1945 (VEI 4), March 1 - December 1, 1938 (VEI 3), March 1926 (VEI 4)...
Potential hazards posed by this volcano are ash plumes, ash falls, lava and pyroclastic flows, hot avalanches and lahars. The volcanic dangerous zone threatened by lava and pyroclastic flows, hot avalanches does not exceed 10 km (6.2 miles) from the volcano.
Ash falls and lahars present potential hazard for Petropavlovsk-Kamchatsky (27 km / 16 miles to the south-south-west from the volcano), Yelizovo (30 km / 18 miles to west-south-west) and other settlements situated close to the volcano.
Avachinsky volcano exposes potential hazard to the Kamchatkan airports and aircrafts flying over Kamchatka because its eruptive clouds can rise to a height up to 10 - 15 km (33 000 - 49 000 feet) above sea level and extend for hundreds of kilometers.
Ash falls are possible at Petropavlovsk-Kamchatsky, Yelizovo, and Vilyuchinsk (55 km /34 miles to the south-west).
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 the parasitic volcano Kozelsky, which has a large crater breached to the NE.
A large horseshoe-shaped caldera, breached to the SW, was created when a major debris avalanche about 30 000 - 40 000 years ago buried an area of about 500 km2 (193 mi2) 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 eruptive products have been explosive, with pyroclastic flows and hot lahars being directed primarily to the SW by the breached caldera, although relatively short lava flows have been emitted.
The frequent historical eruptions have been similar in style and magnitude to previous Holocene eruptions. This volcano is located within the Volcanoes of Kamchatka, a UNESCO World Heritage property.
Featured image: Avanchinsky volcano rising above Petropavlovsk, Kamchatka, Russia. Credit: Google Earth