Sometimes volcanoes just do not mess around.
There’s already a post scheduled for tomorrow about a volcano that rumbled for three months before delivering a blow that killed 30,000 people (they didn’t know they were at risk – it was 1902). This week’s eruption at Shindake is so impressive, though, I wanted to post this today.
Here is a machine translated report of the human reaction on the island after Shindake’s eruption. Reportedly all 137 people on the island made it out all right.
Shindake is in Kagoshima Prefecture, but it is not part of Aira Caldera (Sakurajima is the active cone there). Rather, it is part of Kuchinoerabujima, sometimes called a volcano but described by the Smithonsian’s Global Volcanism Program (GVP) as an island with a group of stratovolcanoes (Furudake, Shindake, and Hachikubo, I think, and probably others) at its eastern end.
It appears from this machine-translated online report (I could find little in English) that the geological history of Kuchinoerabujima is not well known. However it has been mapped (Shindake is circled below):
Kuchinoerabujima is the largest volcanic island in the Satsunan Islands, per a machine translation of Japanese Wikipedia.
Shindake is the youngest of these cones. It formed when Furudake, a taller cone, broke open in an explosion. That looks to have happened around 1450 BC, per the GVP eruptive history report. Shindake has had many explosive eruptions since the 1840s, some of them lethal. Eruptions have generally been put at VEI 2 although there have been VEI 3 eruptions, and in 1933 it had a VEI 4 eruption. The last time it went off – a VEI 1 – was in August 2014, triggering a pyroclastic current, too.
Per the GVP, that August 2014 eruption happened after 19 years (1980-2009) of elevated seismicity and tremor following a small eruption at Shindake in 1980. More recently, seismicity was high between May 18 and May 22, 2015, with steam plumes, fumaroles, and incandescence all being observed. Reportedly, too, ground deformation had been detected. Thus, while the eruption shown above was a dramatic surprise to most of us, the scientists knew something was on the way; they just couldn’t say for sure how big it would be and when it would happen.
Per this machine-translated report, JMA is keeping the alert level for Shindake at 5 (the highest), warning that the level of activity is still high and a possibility of more strong eruptions remains.