Mount St. Helens Geology Lesson: ‘Trashcano’

Forty years ago, Mount St. Helens, an active stratovolcano in Southwest Washington, erupted killing 57 people and covering much of the northwest in ash. The major eruption on May 18, 1980 remains the deadliest and most economically destructive volcanic event in U.S. history.

To honor the anniversary, Chad Pritchard, chair of the EWU Geology Department, created a “trashcano” to model how gas bubbles can grow and lead to Plinian eruptions. Because he couldn’t share the geology lesson with students in person, he created the video below to share with campus. Do not try this at home.


To learn more about the Eastern Washington University Geology Department and the programs offered to students, please visit the geology website.

Have Feedback?

We strive to make this website the best it can be. If you have questions or comments about this website, we welcome your input. Let us know what you think.