A catastrophic event took place on May 18 1980, the erupton of Mt St. Hellens! Mt St.Helens builds up each time after eruption by pushing lava out of the lava dome and gragually gets bigger. It will keep rebuilding and erupting for a long time! During each eruption Mt St.Helens change the earth by filling the rivers, raising the lakes, and smooth out the landskape with mud and layers of ash. One website I saw on the internet said, "Many of these layers formed as debris slid down the side of the volcano and as mudflows and pyroclastic flows (containing volcanic ash, rock fragments and hot gasses) covered the landscape around the volcano, adding layer apron layer to the surface." Over the course of time, Mt St. Hellen's has changed the shape of itself, and the land surrounding it.
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