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