Post-eruption
View of Mt St Helens shortly after the May 1980 eruption. Spirit Lake in the foreground filled with floating timber. The apron in front of the breached crater contains debris avalanche deposits overlain by later pyroclastic flow deposits.
Courtesy US Geological Survey
Professional Paper 1250
Lipman, P.W., and Mullineux, D.R., eds., The 1980 Eruptions of Mount St. Helens, Washington: U.S. Geological Survey Professional Paper 1250 [link to pdf]