Geography

Volcano case studies.

?

Volcano Case Study. MEDC: Mt St Helens, North Ame

  • Located in the Cascade Range, Washington, USA.
  • Had been dormant (asleep) for many years.
  • Showed signs of erupting in March 1980 by minor earthquakes and steam with ash erupted.
  • The expected, but unpredictable eruption occured 8:32am on 18th May 1980.
  • Earthquake measuring 5.1 on the Richter Scale caused a landslide on the northern side of the volcano. (Biggest landslide ever recorded). This removed pressure from the top of the volcano and allowed the eruption to happen.

Primary effects.

  • Huge land slide (Biggest ever recorded).
  • Wiped out all living things 27km north of the crater.
  • Trees uprooted and thrown around like match sticks.
  • 57 people died (One of whom was volcanologist David Johnston studying the volcano).
1 of 4

Secondary effects.

  • Spirit lake (local lake) polluted with volcanic gases.
  • Roads blocked with 1 metre of ash in places.

Short term responses.

  • Mobilising helicopters for search and rescue.
  • Stranded tourists helped to find shelter.
  • Ash cleared from roads in 3 days.

Long term responses.

  • Bridges and roads rebuilt.
  • Drainage looked at to prevent risk of flooding.
  • Forests to north of the crater replanted.
  • Tourism in creased with provision of extra tourist facilities.
2 of 4

Volcano Case Sudy. LEDC: Montserrat, Caribbean,

  • Volcano: Chances Peak, Soufriere Hills.
  • First erupted July 18th 1995.

Immediate effects.

  • Pyroclastic flows.
  • 19 people died.
  • Southern part of the island including the capital Plymouth was destroyed.
  • Island relied on Britian to send over aid and vital supplies.

Long term effects.

  • Plymouth, the Capital City, was buried in ash.
  • Plans put in place in case of futire eruptions.
3 of 4

Short term responses.

  • Evacuation.
  • Search for survivors.
  • Seek aid from other countries/organisations.

Long term responses.

  • 8,000 people out of a possible 12,000 left the island.
  • Rebuild new settlements at the opposite end of the island to the volcano.
  • Return some of the inhabitants that had evacuated.
4 of 4

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »