Explosive deposits following the first rainy season after the erupt...
Detailed Description
Second of two photographs showing what happened during the first rainy season after the explosive eruption of Mount St. Helens in 1980. The eruption generated a large pyrocalstic surge and tephra fall that deposited loose gravel-sized and sand-sized rock debris to a thickness of about 1 m and leveled nearly all vegetation in this area, about 8 km northeast of the volcano.