Figure 2: Fine layering was produced within hours at Mt St Helens on June 12, 1980 by hurricane velocity surging flows from the crater of the volcano. The 25-foot thick (7.6 m), June 12 deposit is exposed in the middle of the cliff. It is overlain by the massive, but thinner, March 19,1982 mudflow deposit, and is underlain by the air-fall debris from the last hours of the May 18, 1980, nine-hour eruption. http://creationontheweb.com/content/view/1541/