1.5 - Congo

Question 1

Where is Mt. Nyiragongo?

Answer 1

The Democratic Republic of Congo

Question 2

When were there major eruptions?

Answer 2

1977 and 2002

Question 3

How wide is the continuous lava lake?

Answer 3

2km wide

Question 4

This mountain is responsible for ____% of Africa’s volcanic eruptions

Answer 4

40%

Question 5

What type of volcano is it?

Answer 5

Shield volcano

Question 6

How many people were effected in 2002?

Answer 6

147 killed, 400,000 evacuated

Question 7

What are some features of lava flows?

Answer 7

• molten magma on the Earth’s surface
• so hot, it flows
• viscosity determined by the amount of silicon dioxide
• buildings can be burnt and covered if its running
• 1977: lake wall collapsed and lava drained in 1 hour, flowing at a rate of 6km/s across 9km, swamping villages while people were asleep

Question 8

What are some features of gas/steam emissions?

Answer 8

• H2O vapour: heavy rainfall events, then potentially lahars
• steam escapes through geysers
• SO2 forms very fine particles that gets into the stratosphere
• SO2 also causes acid rain which corrodes buildings and affects vegetation
• Fluorine gas is poisonous in high concentrations and contaminates farmland or water supply
  CO2 - need 700 eruptions a year to match human cause emissions

Question 9

What are some features of ash/tephra

Answer 9

• carried into the atmosphere, potentially even transboundary
• most falls locally, causing roofs to collapse, choke machinery and electronics, breathing difficulties for animals and people, bury crops and vegetation
• disrupts flight paths of planes - abrasion of fuselages and engine blades

Question 10

What are some features of lahars?

Answer 10

• water mixed with volcanic deposits, flowing rapidly along existing valleys
• could be caused by heavy rain, or maybe volcanic ash as seeded quite humid air, causes condensation, clouds and rain
• they’re very fast and carry large amounts of material and because they’re funnelled into valleys they even faster and pick up even more water
• can go 60km/hr and be 50m deep

Question 11

Volcanic hazards

Answer 11

• lava flows
• domes
• pyroclastic fall
• lateral blast
• volcanic gases (climatic effects)
• health effects of gases
• pyroclastic flows
• pyroclastic surge
• lahars/floods
• structural collapse/debris avalanche
• earthquakes/ground inflation
• tsunami