Directed volcanic blast

The initial eruption of Mount St. Helens, on 18 May 1980, was a directed blast. This blast was a result of depressurization triggered by an earthquake initiated landslide on the north flank of the volcano. Everything within eight miles of the directed blast area was either removed or destroyed. Several people were killed. Between 8 and 19 miles of the volcano, trees were flattened and resembled toothpicks aligned in a uniform direction on surrounding hillsides. Greater than 19 miles from the volcano, trees were seared black due to hot gases.
(E) Emanations of other problems