27: New eruptive phase reported at Ecuador’s Tungurahua Volcano


January 31, 2014 ECUADOR A new eruptive phase has begun at the volcano. Since the early morning today, the seismic network detected an increase in earthquakes including signals of small explosions and long-period events and tremor typical for internal fluid movements (gasses and magma). The Tungurahua volcano Observatory while unable to make direct visual observations received reports from observers that fine black ash fell in Pungal and Penipe, and minor amounts in Palictahua. The black color of the ash suggests that it originates from fresh (so called juvenile) magma. The last eruptive phase of Tungurahua was between 6 Oct and 13 Nov past year and consisted in strombolian-vulcanian explosions generating ash columns rising up to 4 km, accompanied by strong shock waves and producing occasional pyroclastic flows. Bursts of moderate to strong intensity tremor characterized seismic activity during that period. Since 13 Nov, activity had decreased markedly and the volcano only showed weak degassing and no signs that could have been interpreted as precursors to the current new activity, IGPEN mentions in its latest bulletin. This implies that the magma that started the current new phase of activity has risen very quickly from a deeper reservoir into the shallow plumbing system of the volcano. In other words, eruptions at Tungurahua can start with little or even no warning. –Volcano Discovery



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