Unexpected Indonesian Volcanic Eruption Triggers Mass Evacuation


Robin Andrews

Science & Policy Writer

The Mount Barujari eruption (pictured) began on September 27, 2016, without warning. AP Photo/Denda Wiyana Putri

Indonesia, thanks to its positioning atop a battle between two titanic tectonic plates, is pockmarked with nearly 130 active volcanoes. One of them, Mount Barujari on Lombok Island, is erupting quite furiously at the moment, and thousands of people have been evacuated from the area.

The volcano, also known as the Child of Rinjani as it sits within the larger Mount Rinjani caldera, erupted with almost no warning on the afternoon of Tuesday, September 27, spewing out volcanic bombs and generating an ash cloud at least 2,000 meters (6,560 feet) high. Flights in the region have been grounded.


A popular climbing spot, a mass evacuation was swiftly ordered, and fortunately no one appears to have been injured or killed by the violent outburst. Volcanologists are carefully monitoring the situation, but so far, no major damage has been done.

“We are still searching for about 389 other tourists, mostly foreign tourists, to find out their condition and to evacuate them immediately,” a spokesperson from the Disaster Mitigation Agency said, as reported by The Guardian.

According to the Jakarta Post, residents have been urged to stay cautious. After all, the monstrous Mount Rinjani, which features a 6-by-8.5-kilometer (3.7-by-5.3-mile) cauldron-like pit, has a particularly destructive history.

Just back in August, another ash column was seen rising 9,754 meters (32,000 feet) from the summit. A chunk of rock got lodged inside the vent of the volcano, which caused a sudden and powerful pressure build-up over a short space of time.


Segara Anak, the crater lake within Rinjani. Thorsten Peters/Wikimedia Commons; CC BY-SA 3.0

Back in 1994, 172 separate explosions generated enough ash and airborne lava to cause several pyroclastic flows. Although no one was killed by them, subsequent rainfall transformed the deposits into lahars – quick moving mud flows – that cascaded down the slopes of the mountain and robbed 30 people of their lives.

The enormous caldera in which these smaller volcanoes are nested was formed during the 13th century. Registering as a 7 on the Volcanic Explosivity Index (VEI) – whose highest ranking is an 8 – it unleashed over 100 cubic kilometers (24 cubic miles) of volcanic debris, roughly equivalent to 38,500 Great Pyramids of Giza.

Sulfur particles blanketed the globe and caused sudden regional cooling that brought about agricultural failure and widespread famine. It may have been the most powerful volcanic eruption since the invention of writing.


This type of volcanic cataclysm isn’t unique to the region. Right next door, between Java and Sumatra, is Krakatoa, infamous for the 1883 caldera-forming blast that destroyed 70 percent of the island, killed 40,000 people through ash suffocation and tsunamis, and caused chaotic weather across the world for five years.

There’s no evidence to suggest that a huge magma source beneath Rinjani is priming itself for a huge eruption, but this current activity is a another reminder that, one day, a repeat of its 13th-century fireworks is more than likely.


  • tag
  • volcano,

  • eruption,

  • history,

  • Indonesia,

  • caldera,

  • ring of fire,

  • Child of Rinjani,

  • thousands of tourists,

  • Mount Barujari