Kelut volcano (East Java, Indonesia): eruption update - 4 fatalities, new size estimates
Sat, 15 Feb 2014, 13:4213:42 PM | BY: T
Ash emissions from Kelut yesterday (photo taken from Blitar)
Traces of recorded infrasound waves pointing back to Kelut (CTBTO, facebook.com/CTBTO)
Additional details and new estimates about the recent explosion are emerging. Unfortunately, a 4th fatality caused by the eruption has now been confirmed by BNPB. All victims were within 7 km of the volcano. More than 100,000 people have been evacuated.
Ash emissions from Kelut yesterday (photo: @hilmi_dzi / Twitter)
Fast rise of magma?
One of the most remarkable aspects of the eruption was how quickly it built up, suggesting a very fast rise of magma occurred in the hours before the explosion. VSI mentioned that there were only 2 hours between the appearance of shallow earthquakes (the typical immediate precursors) and the onset of the eruption itself. With such little warning time, it was difficult to implement an effective evacuation, but still, one should recognize that Indonesian authorities have done a marvelous job. Still, it is a small wonder that there were not many more fatalities. Most of this is to be attributed to the fact, that the eruption seems not to have produced any or at least no larger pyroclastic flows (which in itself is also a small wonder).
New estimates of the size of the eruption
The latest estimates of the erupted tephra volume are in the range of 120-140 million m3, which puts the explosion into the subplinian category with a low 4 on the Volcanic Explosivity Index scale (VEI). The plume seems to have reached up to 20 km altitude, analysis of satellite data suggest. These values put the eruption to be the largest in recent years, since the 2010 eruption of Puyehue-Cordon Caulle in Chile.
The explosion produced also one of the largest-ever recorded volcano-related infrasound waves. The pressure waves were picked up by stations all over the world, the furthest one being IS53 in Fairbanks, Alaska at >11.000 km or >6.800 mls, and the calculated traces point all into the direction of Kelut.
Fri, 14 Feb 2014, 19:58
Ash from the eruption is still drifting over the eastern Indian Ocean. More than 100,000 people have reportedly evacuated areas close to the volcano. Heavy ash fall occurred in vast areas of Java. A preliminary judgement of the erupted ash suggests that the explosion was a magmatic event, i.e. triggered by a new bash of fresh magma that seems to have risen very quickly to the surface: Read all