St. Helens Volcano Washington, USA. May 1980 Samantha, Jennifer & Bryan

Classification Category: Geological Hazard Date/Place: Washington, DC, USA. May 18 th, 1980 Population: Killed 57 people

Consequences Flattened 570 square km of forest land 300,000 two bedroom homes gone Snapped 6000 tress. Caused glaciers to melt creating mudslides and flooding 46 billion gallons of water slid down the mountain Ash covered sky and went feet in the sky The eruption killed 7000 large animals and hundreds of thousands small animals Caused billions of dollars in damage Destroyed 27 bridges

Natural hazards faced The eruption caused or can cause: Mudslides Mudflow Earthquakes Flooding Contaminated lakes Ruined shipping channels in Columbia River

Frequency St. Helens Volcano has volcanic activity every hundred years but is 40, 000 years old Duration The volcanic activity happened in early May The eruption happed May 18, all day Extent The eruption affected Washington and Columbia The lava damaged up to 600 square kilometers around the volcano.

Speed of onset Volcano was expected to erupt sometime in the 1980’s Until occurring earthquakes that hit in early May. Then St. Helens eruption happened quite quickly but with lots of time to prepare Spatial Dispersion The area around the volcano is likely to be affected Southern Seattle and Washington were affected the most being the closest to the volcano

Temporal Spacing Even though the volcano is considered young ( years old) St. Helen’s erupts almost every hundred years but recently it has been very active It was a random eruption on May 18, 1980