Mount St. Helens

High school (ages 12+)
Environment & Earth

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/mount-st-helens

1. How high is Mount St. Helens?
2. What is the geological classification?
3. What is the primary eruption mechanism (1980)?
4. What happened at Mount St. Helens in 1980?
5. Why did the eruption of Mount St. Helens look different from other volcanoes?

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. How high is Mount St. Helens?Reduced by approximately 1,314 feet (400 meters)
2. What is the geological classification?Active stratovolcano within the Cascade Volcanic Arc
3. What is the primary eruption mechanism (1980)?Lateral blast triggered by a magnitude 5.1 earthquake
4. What happened at Mount St. Helens in 1980?On May 18, 1980, a big earthquake triggered a sideways eruption that sent ash, gas, and rock outward at over 300 miles per hour. It destroyed 230 square miles of forest, 200 homes, and many bridges.
5. Why did the eruption of Mount St. Helens look different from other volcanoes?Instead of shooting up, the eruption blasted sideways in a giant debris avalanche, creating a one‑mile wide horseshoe‑shaped crater.

Stratovolcano: A large, conical volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash.
Pacific Ring of Fire: A major area in the basin of the Pacific Ocean where many earthquakes and volcanic eruptions occur due to tectonic plate movement.
Lateral Blast: An explosive volcanic eruption that ejects material horizontally rather than vertically, often with immense destructive force.