Tuesday 22 October 2013

Ash cloud from Russian volcano disrupts Alaskan air traffic.

Mount Kluchevskoi, an extremely active volcano on the Kamchatka Peninsula in the Russian Far East, underwent a particularly large eruption on Saturday 19 October 2013, producing a 10 000 m high ash column that drifted into Alaskan airspace over the weekend, leading to the cancellation of three flights from Alaskan airports, as well as delays to other services. The volcano produced a second major column on Sunday 20 October, this one around 8000 m high, and in addition has been ejecting incandescent material onto its slopes and producing lava flows on its flanks.

Eruption on Mount Kluchevskoi on Sunday 20 October 2013. Yuri Demyanchuk/Institute of Volcanology and Seismology of the Far Eastern Branch of the  Russian Academy of Sciences/Kamchatka Volcanic Eruption Response Team.

Kluchevskoi began erupting in August 2013, after a break of about ten months. The current series of eruptions has been going on for about a week, but started causing problems for Alaska at the weekend after a change in the wind direction. While Kluchevskoi presents an occasional problem for air traffic, it seldom harms people on the ground, though this is largely because nobody chooses to live near to it.

The Kamchatka Peninsula lies on the eastern edge of the Okhotsk Plate, close to its margin with the Pacific and North American Plates. The Pacific Plate is being subducted along the margin, and as it does so it passes under the southern part of the Kamchatka Peninsula, and as it does so is partially melted by the friction and the heat of the Earth's interior. Some of the melted material then rises through the overlying Okhotsk Plate as magma and fueling the volcanoes of southern Kamchatka.

The approximate location of Mount Kluchevskoi. Google Maps.


Follow Sciency Thoughts on Facebook.