mt st helens

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Mt St Helens- Washington USA -1980
- General information
  - lies near to a destructive plate boundary
  - part of the Cascade mountain range
- Environmental impcts
  - Spirit lake filled in by landlside
  - flood risks were increased
  - 250km2 of forestry was destroyed
  - 250km of river ecosystem destroyed by lahars
trigger stimulus was a small earthquake
- this caused a bulge which became unstable and collapsed
- General information
  - lies near to a destructive plate boundary
  - part of the Cascade mountain range
Social impacts
- communications disrupted
- 56 people died
- lahars destroyed 200 homes
- 27 bridges, 185 miles of road and 15 miles of railway destroyed
Responses
- helicopters flew in
- ash was cleared from towns
- the big rivers were dredged
- new tourist facilities built
- volcano monitored
- houses rebuilt
- new plans to prepare and warn people
- exclusion zone was set up
- bridges rebuilt with a wider span
- Mt St Helens- Washington USA -1980
  - Environmental impcts
    - Spirit lake filled in by landlside
    - flood risks were increased
    - 250km2 of forestry was destroyed
    - 250km of river ecosystem destroyed by lahars

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