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Avacha Volcano

2007 Schools Wikipedia Selection. Related subjects: Geography of Asia

                 Avachinsky
   Avachinsky, seen from base camp.
   Elevation     2,741 metres (8,993 feet)
   Location      Kamchatka, Russia
   Coordinates   53°15′N 158°50′E
   Type          Stratovolcano
   Last eruption 2001
   Easiest route basic rock/snow climb

   Avacha Volcano (Avacha, Avachinsky) (Russian: Авачинская сопка, Авача)
   is an active volcano on the Kamchatka Peninsula in the far east of
   Russia. It lies within sight of the capital of Kamchatka Oblast,
   Petropavlovsk-Kamchatsky. Together with neighbouring Koryaksky volcano,
   it has been designated a Decade Volcano, worthy of particular study in
   light of its history of explosive eruptions and proximity to populated
   areas.

Geological history

   Avachinsky lies on the Pacific Ring of Fire, at a point where the
   Pacific Plate is sliding underneath the Eurasian Plate at a rate of
   about 80 mm/year. A wedge of mantle material lying between the
   subducting Pacific Plate and the overlying Eurasian Plate is the source
   of dynamic volcanism over the whole Kamchatka Peninsula.

   The volcano is one of the most active volcanoes on the Kamchatka
   Peninsula, and began erupting in the middle to late Pleistocene era. It
   has a horseshoe-shaped caldera, which formed 30-40,000 years ago in a
   major landslide which covered an area of 500 km² south of the volcano,
   underlying the city of Petropavlovsk-Kamchatsky. Reconstruction of a
   new cone inside the caldera occurred in two major eruption phases,
   18,000 and 7,000 years ago.

Recent activity

   Avanchinsky Summit
   Enlarge
   Avanchinsky Summit

   Avachinsky has erupted at least 17 times in recorded history. Eruptions
   have generally been explosive, and pyroclastic flows and lahars have
   tended to be directed to the south west by the breached caldera. The
   most recent large eruption ( VEI=4) occurred in 1945, when about
   0.25 km³ of magma was ejected. The volcano has since had small
   eruptions in 1991 and 2001.

   The volcano continues to experience frequent earthquakes, and many
   fumaroles exist near the summit. The temperature of gases emitted at
   these fumaroles has been measured at over 400°C. In light of its
   proximity to Petropavlovsk-Kamchatsky, Avachinsky was designated a
   Decade Volcano in 1996 as part of the United Nations' International
   Decade for Natural Disaster Reduction, together with the nearby
   Koryaksky volcano.

   Avachinsky (centre, nearest coast) from space
   Enlarge
   Avachinsky (centre, nearest coast) from space
   Retrieved from " http://en.wikipedia.org/wiki/Avacha_Volcano"
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   with only minor checks and changes (see www.wikipedia.org for details
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