For pre-historic eruptions, this scale is calculated based upon the dispersal of the volcanic products- i.e. how far and wide they are scattered. Volcanic eruptions that have very tall columns will spread tephra far and wide.
last modified: 05/21/2004 13:24:30
URL: http://wwwacs.gantep.edu.tr/docs/tut/tut29a_ex/height.html