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North Flank of Mount St. Helens

Detailed Description

This view from near the Forest Learning Center along Highway 504 shows the north flank of Mount St. Helens, from which much of the debris from the massive 1980 avalanche/eruption spilled into the Toutle River valley. The eruption produced about 3 cubic kilometers of ash and sediment that was distributed across the landscape around the volcano. This material is being transported downstream, causing economic damage to the communities and infrastructure (Costa, 1994). In the years since the eruption, the major streams in the valley have re-established themselves. Shrublands, forests, and aquatic ecosystems are gradually re-establishing themselves. However, large, barren expanses along the streams and in the badlands-style debris fields on and around the volcano are still a source of dust (ash) on dry, windy days.


Public Domain.