Volcano Impacts Case Study - Indonesia (EDC)

Question 1

How many eruptions has Indonesia experienced in recent history?

Answer 1

At least 80 eruptions, however this could be an underestimate.

Question 2

How do fatalities and destruction from volcanic eruptions in Indonesia compare to other countries?

Answer 2

Indonesia has suffered more eruptions causing fatalities (114 separate eruptions) and destruction than any other country.

Question 3

How long is the area of subduction along the Indonesian archipelago?

Answer 3

3000km.

Question 4

What makes volcanic eruptions in Indonesia so impactful?

Answer 4

Indonesia has a number of highly explosive volcanoes, the most famous of which being Krakatoa.

Question 5

What type of volcano is Mount Merapi?

Answer 5

A strato-volcano.

Question 6

How tall is Mount Merapi?

Answer 6

Nearly 3km.

Question 7

Prior to 2010, what years were Mount Merapi’s 4 most recent eruptions?

Answer 7

1994, 1997, 2001 and 2006.

Question 8

Which two factors show the highly explosive nature of Mount Merapi’s 4 frequent eruptions?

Answer 8

• All 4 eruptions were 3-4 on the VEI.
• All eruptions caused a dome collapse, producing pyroclastic flows.

Question 9

When did Mount Merapi experience a major eruption?

Answer 9

Between October 26th and November 12th 2010.

Question 10

How many people were killed, injured or displaced by the 2010 Mount Merapi eruption?

Answer 10

• 367 killed.
• 277 injured.
• 410,000 displaced.

Question 11

What VEI value did the 2010 Mount Merapi eruption have?

Answer 11

4.

Question 12

How far did pyroclastic flows and lava bombs from the 2010 Mount Merapi eruption travel respectively?

Answer 12

• Pyroclastic flows travelled up to 15km.
• Lava bombs were launched up to 4km in all directions.

Question 13

How did the time of year worsen the impacts of the 2010 Mount Merapi eruption?

Answer 13

The eruption occurred during the rainy season, causing lahars.

Question 14

What impact did ash falls and sulphur dioxide emitted from the 2010 Mount Merapi eruption have respectively?

Answer 14

• Ash falls caused Yogyakarta airport to close for over 14 days.
• Sulphur dioxide caused acid rain over a large area.

Question 15

How much material did ash falls and pyroclastic flows from the 2010 Mount Merapi eruption contain?

Answer 15

130 million cubic metres of material.

Question 16

What three benefits does Indonesia get from being in a tectonically active location?

Answer 16

• Farming is productive due to the tropical climate and fertile volcanic soils, allowing intensive farming of crops such as rice which can be grown up to three times in a year.
• Geothermal power generates 3% of Indonesia’s electricity, such as the 350 MW Sarulla power plant, which is one of the largest geothermal plants in the world.
• Minerals can be mined from volcanoes for industrial processes, such as sulphur which is used to produce chemicals.