Background Information


Geologic Setting 
Karymsky Volcano is part of the Eastern Volcanic Front on the Kamchatka Peninsula in eastern Russia.  The volcanic arc is the result of the Pacific plate subducting beneath Eastern Asia and subsequent melting (Izbekov et al., 2004).  The Karymsky Volcanic Center is located about 30 km west of the Pacific coast and is composed of a group of volcanoes, calderas, and maars all constructed since the Pliocene (Walter, 2007).  
Google Earth image illustrating the northwest movement and subduction of the Pacific plate beneath the North American and Eurasian plates.  The result of subduction is a chain of volcanoes extending across the North Pacific to Kamchatka and south to Japan.  



Karymsky Volcano is a stratovolcano nested within the 5 km diameter Karymsky caldera that collapsed approximately 7.9 ka due to a catastrophic eruption (Braitseva & Melekestsev, 1991).  Karymsky Volcano is located 9 km north of Academy Nauk caldera, which is filled in by Karymsky Lake.  A north-south trending fault connects the two major calderas, which produces numerous hot springs and geysers (Izbekov et al., 2004).

Simplified geologic map and a landsat-4 image of Karymsky Volcano and Academy Nauk caldera modified from Izbekov et al., 2004.  Karymsky Volcano almost complete fills a 7900 yr caldera.  Academy Nauk Caldera located 9 km to the south formed ~40 ka.  The two prominent features are thought to share a magma plumbing system along the north-south fracture fault (Modified from Izbekov et al., 2004 p. 2327 ).   

Volcano Dimensions
Karymsky is a symmetrical stratovolcano that rises 900 m above the caldera floor and 1540 m above sea level (asl).  The volcano is 4.6 km wide and has 20-35° slopes (Walker, 2007).  Geophysical evidence indicates the presence of one or more magma chambers located between 1-5 km below sea level respectively (Walter, 2007).  

A Vulcanian-Strombolian eruption at Karymsky volcano in July, 2008 can be seen from the Academy Nauk caldera 9 km to the south.  Eruptions of this size are very frequent at Karymsky volcano
(Photo courtesy of Pavel Izbekov - UAF).  

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