X1011735853-00174-42175</DOCNO> CVO PROJECT - Volcanoes, Snow, and Water - Mt. St. Helens - LAHARS USGS/Cascades Volcano Observatory, Vancouver, Washington Geology of Interactions of Volcanoes, Snow, and Water: Mount St. Helens, Washington Lahars formed by pyroclastic surge swiftly melting snowpack on 18 May 1980 The initial explosions at Mount St. Helens on 18 May 1980 developed into a huge, hot flow (so-called "pyroclastic surge") that generated catastrophic floods off the east and west flanks of the volcano.
(Washington Lahars; formed; by pyroclastic surge) (The initial explosions at Mount St. Helens on 18 May 1980; developed; into a huge, hot flow) (Washington Lahars formed by pyroclastic surge swiftly melting snowpack on 18 May 1980 The initial explosions at Mount St. Helens on 18 May 1980 developed into a huge, hot flow; generated; catastrophic floods)
Washington Lahars The initial explosions at Mount St. Helens on 18 May 1980 Washington Lahars formed by pyroclastic surge swiftly melting snowpack on 18 May 1980 The initial explosions at Mount St. Helens on 18 May 1980 developed into a huge, hot flow
formed developed generated
by pyroclastic surge
into a huge, hot flow
catastrophic floods