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Villarrica, Chile
View from approach to national park.
- Villarrica is an open system basaltic
volcano with a long historic record that includes four fatal eruptions.
A very large (VEI=5) eruption was dated ca. 1810 BC by the carbon-14
method. The first historic eruption was recorded in 1558. Since then,
there have been at least 54 small to moderate eruptions. There have
been two moderate-large eruptions in 1640 and 1948.
- Mudfows, associated with eruptions,
killed a total of at least 73 people in 1949, 1963, 1964, and 1971.
The mudflows of 1971 were caused by lava flows that melted ice. Many
homes and agricultural installations were destroyed in the Chaillupen
and Turbio Valleys. Concrete bridges across major bridges were also
cut. About 350 people were killed in Villarrica village by a tectonic
earthquake in 1575.
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October 26, 1999
- On 17-18 October, the Villarrica Volcano
exhibited strong Strombolian eruptions at irregular intervals from
its central crater. Showers of fluid bombs fell on the crater rim
and upon the upper S and W flanks. Tephra covered the upper flanks
of the cone.
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October 12, 1999
- Seismic activity at the Villarrica
Volcano has increased since 22 August. Increased amplitude in harmonic
tremor signals have been noted. Periods of high amplitude tremor lasted
2-30 hours, alternating with background level tremor. On 15 September,
an energetic LP event is considered to have been associated with a
small explosive event in the crater. On 4 October, new ash and projectiles
were observed on the crater rim and indicate that a small explosive
event occurred. Hybrid earthquakes have also been increasing in number
since 1 October. The OVDAS has recommended that local authorities
move to a Level 2 (Green) in the "Semaforo" (traffic light)
alert scheme adapted for the volcano. If the harmonic tremor increases
in amplitute or high levels are maintained for long periods recommendations
will be made to move to Level 3 (Amber).
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