Indonesia- Mt Merapi

Type of boundary + plates

Convergent/destructive (oceanic-oceanic)

Indo-Australian subducts beneath Eurasian

Type of volcano

highly active, explosive stratovolcano, part of island arc. Typically VEI 2-3, occasionally 1,4.

Population within 5km

49,025

Impacts of eruptions

-dome collapse= pyroclastic flows up to 15km (2010)

-lava bombs thrown as air bubbles burst near surface (reaching up to 4km)

-ash mixes with monsoon rains (>1800mm/annum) causing lahars

-ash fall buries land

-SO2 can cause acid rain

-volcanic EQs

Impacts on indonesia

-Livestock killed

-ash, lahars and pyroclastic flows destroy crops and infrastructure

-acid rain damages vegetation

-river channels choked

-Yogyakarta airport closed for 2 wks

-410,000 refugees to be accommodated

-367 killed, 277 injured

Reasons for living nearby

-islands created by volcano

-fertile soil- staple crops eg rice

-intensive farming = popu growth = denser popu

-geothermal potential

-mineral mining (eg sulphur)

-emotional attachment

-spiritual

Indonesia GNI per capita

$12,400 EDC

Mitigation against event

River channels cleared to reduce flooding and contain lahars

Mitigation against vulnerability

-centre for volcanology and geological hazard mitigation (CVGHM) established in 1920. Volcano Observation Section started to slowly monitor certain volcanoes (limited resources and tech eg seismometers)

-Gradual improvement to equipment and monitoring- >60 volcanoes monitored and hazards mapped

-CVGHM works with locals to prepare

-settlement forbidden on Merapi’s highest slopes (near the crater)

-villages on southern slopes encouraged to relocate (financial/ land incentives)

Mitigation against losses

-limited resources for govt

-poorer farming communities have v few resources to aid recovery

-emergency services (eg military) trained in search and rescue

-temp shelters in safe zones are prepared in eruptions, can be upgraded to permanent if needed