Agence France-Presse “Bali volcano: 34,000 flee Mount Agung as tremor magnitude intensifies” https://www.theguardian.com/world/2017/sep/24/bali-volcano-34000-flee-mount-agung-as-tremors-intensify
Michael McGowan “Bali volcano: will Mount Agung erupt and what happens if it does?” https://www.theguardian.com/world/2017/sep/27/bali-volcano-will-mount-agung-erupt-and-what-happens-if-it-does
Scott Bryan*5, an associate professor from the Queensland University of Technology, says there have been “very good indications” that an eruption is imminent.
“The fact that the seismic tremors beneath the volcano are increasing in number, intensity, and the reduction in their depth in the last week or so, is a very good indication that magma is moving up to the surface,” he said.
As well as seismic activity, Bryan said there are two other signs that an eruption is imminent: gas emissions from the summit, and bulging on the volcano’s surface.
He said gas emissions were a sign that pressure under the ground had become too great, sending magma towards the summit of the volcano and releasing gas and steam in the process.
“It’s like a bottle of Coke or champagne, if you shake them up the pressure builds until you release the lid,” he said.
*2:See Associated Press “Bali on high alert after tremors around Mount Agung volcano” https://www.theguardian.com/world/2017/sep/22/bali-indonesia-high-alert-tremors-around-mount-agung-volcano
*3:See Kate Lamb “Bali volcano eruption could be hours away after unprecedented seismic activity” https://www.theguardian.com/world/2017/sep/26/bali-volcano-eruption-seismic-activity-mount-agung
*4:See Kate Lamb “Mount Agung volcano threat forces Bali to make plans for stranded travellers” https://www.theguardian.com/world/2017/sep/27/mount-agung-volcano-bali-stranded-travellers
*5:See eg. http://qut.academia.edu/ScottBryan