By Simon Redfern
Volcanic Mount Sinbung in Sumatra, Indonesia, has sprung to life in a
series of massive eruptions over the last few days.
The volcano had lain dormant for more than 400 years before a few
minor eruptions three years ago. But over the past week, more than
5,000 people have been evacuated from nearby towns and villages as
Sinbung makes her presence felt.
The volcano erupted an ash cloud more than 6km (4mi) into the air, and
a super-heated avalanche of lava, ash and rock raced down its flanks
at terrifying speeds.
There have been reports of a stream of red hot lava extending a
kilometre or so from the vent.
Sinabung’s activity is fed by the slow tectonic descent of rocks
forming the floor of the Indian ocean, drawn down and northward into
the Earth’s mantle beneath Indonesia. This geological feature is
called the Sunda Arc and it is home to some of the largest volcanic
eruptions ever seen.
The 1815 eruption of Mount Tambara, above the Sunda Arc, remains the
largest recorded volcano ever.
But it is topped by the super-eruption of Toba, also in Sumatra, which
scientists place at 70,000 years ago as the largest in human history.
The eruption of Indonesian Krakatoa was smaller than both, yet was
heard 5,000km (3,000mi) away and caused widespread devastation. More
than 35,000 people are thought to have been killed.
Indonesia, the world’s fourth most populous nation, sits atop a
geological powder keg. This week’s eruption of Sinabung serves as a
reminder.
As Sinabung puts on her show of power, in the Mediterranean the
volcano Etna has also been active. But the view of Etna’s summit is
far more gentle, as extraordinary smoke rings have been puffed into
the Sicilian sky, as if the volcano is sitting back and relaxing for a
while.
Photographer Tom Pfeiffer managed to capture the scene in his
fantastic shots. – BBC Environment
