INDONESIA VOLCANO CASE STUDY

MOUNT MERAPI 2010

Mount Merapi is a strato volcano

4 on the VEI (Icleand 3)

Destructive plate boundary

Pyroclastic flows

SOCIAL IMPACTS

  • 200,000 people were made homeless

  • Emergency shelters had to be moved

  • 353 people were killed from the main eruption

ECONOMIC IMPACTS

  • Large number of livestock were killed

  • Ash falls forced the closure of airport for over a fortnight

  • Many roads closed due to lava flows

However

  • Bought in jobs from the tourism industry

  • Medical use of hot spa water and mud seen to improve health

POLITICAL IMPACTS

  • International aid was offered from organisations such as Red Cross

  • Govt making money available to farmers to help replace livestock

ENVIRONMENTAL IMPACTS

  • Sulphur dioxide emissions caused acid rain to fall over large part of region

  • Conservation area has been set up around volcano where it is unsafe to live

  • Geothermal energy (renewable source) using steam from hot rocks

  • Ash from volcano eventually led to more fertile soil in the area

INDONESIA FACTS:

  • Eurasian Plate, Pacific Plate and Indo-Australian Plate are three avtive tectonic plates that cause the subduction zones that form these volacanoes

  • The PROBLEM is that many local residents refure to leave their homes - can be related to their livelihood - farms which are their only source of income, can also be realted to animist belief-systems - volcano warning signs such as ash and thunder are considered to be acts of their angry ancestors and by praying to local gods local communities believe they will be protected from any danger

TYPES OF ERUPTIONS IN INDONESIA

LAVA FLOWS

  • Speed of lava flows vary from several meters to tens of km/hr before it cools and solidifies

PYROCLASTIC FLOWS

  • Most destructive and deadly event from eruptions

  • Mixture of volanic gases and fragmented rock

  • Flows at high speeds

  • Very high temperatures

TEPHRA FALLS

  • Term from rock fragments released into the air by eruptions

  • Large tephra usually falls not far from crater

  • Lapilli - smaller tephra tend to be found further away

  • Can have huge impacts on human health, environmental pollution, animals

LAHARS

  • Hydro-volcanic events during eruption

  • Large discharge flow, high sediment concentration

MAGMA

  • Earthquakes occur due to magma movement

  • Volcanic islands result from repeated fast placement of magmatic products in a limited area

TSUNAMIS

  • Produced by unavoidable disturbances in marine/lake environments

  • Can cause underwater earthquakes/landslides/volcanic eruptions/collapse of sea floor/bombs

  • Long history of volcano-triggeres tsunamis in Indonesia

Why does Indonesia have so many volcanoes?

There is a widespread subduction zone along the entire 300km length of the Indonesia archipelgo

Much of Indonesia is an island arc formed by subduction of the Indo-Australian plate beneath the Eurasian plate

Continental shelf of northern Australia is in collusion with Eurasian plate - plate movements produce high levels of seismicity and volcanicity