Geologic Background
Massive Mutnovsky, one of the most active
volcanoes of southern Kamchatka, is formed of four
coalescing stratovolcanoes of predominately basaltic
composition. Multiple summit craters cap the volcanic
complex. Growth of Mutnovsky IV, the youngest cone, began
during the early Holocene. An intracrater cone was
constructed along the northern wall of the 1.3-km-wide
summit crater. Abundant flank cinder cones were
concentrated on the SW side. Holocene activity was
characterized by mild-to-moderate phreatic and
phreatomagmatic eruptions from the summit crater.
Historical eruptions have been explosive, with lava flows
produced only during the 1904 eruption. Geothermal
development is planned at Mutnovsky, which has the
highest heat capacity of any volcano in the
Kuril-Kamchatka arc.
Historic Activity:
- There have been 18 reported eruptions since
historical activity began in the 17th century.
- Historical eruptions were explosive, with known lava
flows produced only in 1904.
- The most recent activity was from December 1960 to
January 1961, when weak explosive eruptions sent a
gas-and-ash column 3.5-4 km high.
Recent Activity:
- During field work in Sept. 1993, large rock
avalanches within the summit crater at intervals of
several hours and intense melting of the glacier inside
the crater were observed. Explosions from a vent in the
central part of the crater ejected boiling mud several
meters high.
- On Nov. 25, 1996, a fumarolic plume was observed
rising to a height of 1 km above the crater.
- 20 years of increasing fumarolic activity proceeded
two gas-and-ash explosions on March 17, 2000. Small
phreatic eruption on June 30 and continued fumarolic
activity.
Data Sources:
- Global Volcanism Network (V. 18, No. 8 and V. 25, No.
9).
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