Mount St. Helens

We are here

What Mt. St. Helens looks like now…

What Mt. St. Helens used to look like…

In 1980 Mt. St Helens erupted

http://www.youtube.com/watch?v=-H_HZVY1tT4

What observations can be made about the eruption?

• Write Mt St Helens observations on the top half of the front of your folded organizer

• Discuss with your table groups the observations you made

• Be prepared to share these with the whole class

Class Observations-

What are some ideas as to why this eruption happened?

There was an explosive volcanic eruption because…

There was an explosive volcanic eruption because…•earthquakes and friction caused the eruption•the plates overlap each other and converge and that caused eruption•magma (and maybe ash too) built up and pressure built up , then erupted•pressure/eruption caused earthquake

Initial explanations….

• This is only the first draft, and we will be making revisions as we learn more about volcanic eruptions

• As a table group, use our list of observations and ideas to write an initial explanation to explain why Mt St Helens erupted explosively

Class Observations

• 57 people killed• Earthquake, landslide, prior to eruption• Wildlife killed• Poisonous gases, hot steam, landslide• Ash went mostly to one side, in one direction• 1300 ft of the mountain was blown off• Pyroclastic flow-• Spirit lake was dislocated and smothered- lake bed

was raised• Cone shaped and changed shape of the mountain• Really large, went high upto sky, went outward

covering ground too