A scale for rating the volcanic eruptions according to the volume of material ejected, the height to which the material rises, and the length of time over which the eruption continues.

Abbreviation for volcanic explosivity index. See Newhall and Self (1982).

The Volcanic Explosivity Index, or VEI, was proposed in 1982 as a way to describe the relative size or magnitude of explosive volcanic eruptions. It is a 0-to-8 index of increasing explosivity. Each increase in number represents an increase around a factor of ten. The VEI uses several factors to assign a number, including volume of erupted pyroclastic material (for example, ashfall, pyroclastic flows, and other ejecta), height of eruption column, duration in hours, and qualitative descriptive terms.

VERB EXCHANGE INC