What was the cause of the eruption of mount st Helen's and what effects did it have?

Question

what effects did the eruption have on the enviroment, people and the ecconomy.

Answer 1

Cause of the eruption:

I came across this article published in the New York Times.

"From these clues scientists have deduced that the triggering event on May 18 was a fairly severe earthquake (magnitude 5) that dislodged a gigantic bulge, formed in recent weeks on the mountain's north side. In the largest landslides ever recorded by American geologists, this bulge slipped down the mountain like a vast sliding door.

With this ''door'' open, rock that had become supercharged with highly compressed gas exploded, ejecting to the north a tremendous horizontal blast. The reconstruction has removed uncertainty over whether the earthquake caused the eruption or vice versa. "

http://query.nytimes.com/gst/fullpage.ht...

Effects:

- 57 people were killed

- 400 m lost from the height of the mountain

-  damage bill one billion dollars

- nearly 7,000 large animals (deer, elk, and bear) died – as well as all birds and most small mammals

- 12 million Chinook and Coho fingerlings lost when – hatcheries  destroyed

- estimate - 40,000 young salmon killed - swimming through the turbines (hydro station) – low water and mudflows

- 200 people lost homes

- 47 bridges collapsed

- 185 miles of highway destroyed

- ash was found covering cars over 2000 miles away

- ash act sas a fertilizer as it decomposes adding chemicals to the soil — Palouse area of Washington benefits - grapes

- State of Washington - leading producer of environmental Sulphur Dioxide