Mount Merapi

Question 1

Case study

Answer 1

• Java, Indonesia
• 1,700m high and has been erupting regularly since the 1500s.
• Erupted 26th October 2010
• GDP = $3,475.25
• Stage in DTM = 3
• Active stratovolcano

Question 2

Nature of hazard

Answer 2

• Caused by the Indo-Australian Plate being subducted beneath the Eurasian Plate.
• The volcano is located on a destructive plate margin at a subduction zone and is part of the Pacific Ring of Fire.
• Eruptions are getting worse over time
• VEI = 4

Question 3

Volcano facts

Answer 3

• Age of Rock: 400,000 years
• A part of an island arc
• tall, conical volcano composed of one layer hardened lava, tephra and volcanic ash.
• These volcanoes have a steep profile and periodic, explosive eruptions
• Erupt with terrifying force

Question 4

Primary social impacts

Answer 4

• villages were under 30cm of ash
• 360,000 people were displaced from their homes
• people lost their homes and livelihoods
• The danger area was extended to 20km from the mountain

Question 5

Primary environmental impacts

Answer 5

• Volcanic bombs and hot gases of up to 800°C spread over 11km away
• Pyroclastic flows spread 3km down the mountain
• Ash fell up to 30km away and 5km into the sky.
• Sulphur Dioxide was blown across Indonesia and as far as South Australia.
• crops damaged

Question 6

primary economic impacts

Answer 6

• particularly farmers lost their livelihoods

- Lava flows damaged ski lifts.

Question 7

Secondary social impacts

Answer 7

• Emergency shelters had to be moved over 15 km away.
• 278,000 people living in this area had to flee their homes.
• The evacuation centres were overcrowded leading to poor sanitation, no privacy and serious disease risk.
• 353 people were killed, including Mbah Maridjan and 577 injured

Question 8

Secondary environmental impacts

Answer 8

• Water contaminated with acidic lava and ash.
• Ash, rock and lava deposited on the sides of the volcano was washed away by rainfall into towns creating lahars.
• pyroclastic flows and toxic gas inhalation.
• Sulphur dioxide was blown across Indonesia as far South as Australia.

Question 9

Secondary economic impacts

Answer 9

• vegetable price increased because of the damage to crops
• Planes were grounded in Western Australia because of the risk of damage to aircraft from the ash cloud.
• many people cancelled their trips to indonesia

Question 10

Secondary political impacts

Answer 10

• Ash caused major disruption to airline industry across Asia also.

Question 11

Positive impacts

Answer 11

• Ash from the volcano will eventually lead to more fertile soils in the area
• A conservation area has been set up around the volcano where it is unsafe to live
• The eruption brought volcanic tourism although eruptions can cause tourists to cancel visits. Mineral mining increased.

Question 12

Immediate responses

Answer 12

• 10 evacuation centres were set up either as tents, in schools, churches, stadiums or government offices
• 1,600 people, either volunteers or military, were part of the national aid response
• International aid was offered from organisations such as the Red Cross

Question 13

Long-term responses

Answer 13

• Formal evacuation centres were eventually set up because buildings, such as schools and government offices, were needed for their official uses
• 2,682 people have had to be moved to new, safer houses permanently.
• The government is making money available to farmers to help replace their livestock
• The government has set up a special task force to support people that have been affected by the volcano either by family issues, or because they have lost their jobs
• in the long term more jobs have been created in the tourism industry

Question 14

Management

Answer 14

• Monitoring of the volcano includes 1 seismograph, a set of digital cameras to observe the lava dome and on site sulphur measuring apparatus.
• Small changes in local magnetic fields have been found to coincide with eruptions and tilt measurements show the inflation of the volcano as magma rises.