Case Study: Agung

Geography: Cambridge International GCSE (2027 Exams), topic 4.4.3

Volcano Case Study - Mount Agung, Indonesia

Mount Agung, on the Pacific 'ring of fire' in Indonesia, erupted in 2017. The eruption caused a huge ash plume and lahars.

On the Pacific ‘ring of fire’ where the Eurasian plate and the Indonesian-Australian plate meet.
At this convergent/destructive plate boundary, the Indonesian-Australian plate is subducting underneath the Eurasian plate.
Magma rises along the boundary, making Indonesia a very active area for volcanoes.

Before main eruption:
Shallow tremors for months.
Sulphuric smoke rising to 200m.
Seismic shocks recorded by Indonesia’s national volcanology centre.
27th of November 2017:
Ngurah Rai International Airport was closed as an ash plume rose 9100m into sky.
59,000 people were stranded for 24 hours while ash was in the upper atmosphere.
Ash mixed with local river water causing lahars as the rainy season caused an increase in water.
Ashfall reported in many villages nearby.

The area was put on a level 4 alert on the 25th of September.
Indonesian Red Cross moved 42,714 people outside a 12 km exclusion zone beforehand.
People stayed in town halls, schools and livestock shelters.
The UK, Singapore and Australia issued travel alerts warning of possible flight disruptions or evacuations.
Masks were distributed in Bali and Pulau Lombok to protect people from inhaling ash particles.