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Mount St. Helens FAQs: Frequently Asked Questions and Answers about Mount St.Helens

Frequently Asked Questions and Answers about Mount St.Helens

Mount St. Helens is the most active volcano in the contiguous United States, which makes it a fascinating place to study and learn about. Scientists receive many questions about the volcano, and some of the most frequently asked are compiled below.

Historical Facts about Mount St.Helens

  • Where did the name "Mount St. Helens" come from?
  • What is the early-settlement documentation of Mount St. Helens?

1980 Eruption

  • How high was Mount St. Helens before the May 18, 1980 eruption. How high was it after?
  • How much ash was there from the May 18, 1980 eruption of Mount St. Helens?
  • How far did the ash from Mount St. Helens travel?
  • For additional information, read the website section dedicated to the May 18, 1980 eruption and activity from 1980-1986.

2004-2008 Eruptive Activity

  • How large is the lava dome, and how does it compare to the 1980–1986 dome?
  • What is the evidence that the lava dome stopped growing in 2008?
  • Why is this considered to be a pause? Why is the Alert Level being lowered to Advisory (Color Code Yellow) instead of Alert Level Normal (Color Code Green)?
  • If the eruption resumes, what kinds of precursors are likely to provide warning?
  • What are some of the lessons that scientists learned from the 2004-2008 eruption?
  • For additional information, read the website section dedicated to the 2004-2008 period of volcanic activity.

30 Cool Facts about Mount St. Helens is a poster that lists the answers to some of the most frequently asked questions about the volcano.