Villarrica, a stratovolcano located in southern Chile
erupted spectacularly on 3rd March causing authorities to evacuate
over 3600 people from the vicinity of the volcano.
The volcano, measuring 2847 metres is one the country’s most active volcano with numerous documented eruptions
of which the majority have been a VEI 1 or VEI 2. Villarrica’s most violent
eruptions according to radicarbon dating took place in 1810 (+/- 200) measuring a VEI 5 and in 0670
BCE measuring a VEI 4.
According to the Global Volcanism
Program, Villarrica showed signs of activity in early December last year;
however the activity was minimal and only began to intensify in February 2015. In
early February the volcano experienced an increase in seismicity, sulphur
dioxide emissions, crater
incandescence and lava lake temperature. Strombolian eruptions took
place during early to mid February emitting ash plumes and ejecting tephra
(including lava bombs measuring 5 metres in diameter) several metres high.
From 28th February to
2nd March the volcano showed signs of greater increase in activity
including significant seismic activity, further strombolian activity, ejection
of tephra and an increase in the level of the lava lake. On 3rd March at approximately 03:00 am after an increase in seismic levels the
most significant eruption took place. A lava fountain was produced reaching
heights of 1.5 km, tephra was ejected several metres around the volcano and
lava flows travelled down the volcano. An ash plume was also produced, reaching
a height of up to 8 km and travelled 400 km towards the east.
The Alert Level was raised to Red
from Orange and a 10 km exclusion
was placed as a result of the increased intensity of the eruption. Residents
within this zone including those from the towns of Pucon and Conaripe were evacuated as a
precautionary measure but returned when the intensity of the eruption decreased
later that evening.
Due to a decline in activity on 5th
March, the exclusion zone was reduced to 5 km and the Alert Level was lowered
to Orange. A further decline in
activity continued at the volcano, including decrease in seismicity and the
absence of an active lava lake on 6th March and subsidence of
material in the crater and decrease in gas levels on 9th March. The
Alert Level was lowered to Yellow on 10th March as a result; however
a 3 km exclusion zone remains due to fear of avalanches on the volcano.
Source: Reuters
Source: EPA (Francisco Negroni)
Source: Rocuant/AFP/Getty Images
Source: AP, Aton
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