The Volcanic Explosivity Index (VEI) is a method to gauge the size of a volcanic eruption by using semiquantitative and incomplete historical information. It is intended to be somewhat analogous to the Richter scale for earthquakes.
Description |
Volume of Ejecta in Cubic Meters |
Column Height in Kilometers |
VEI |
non-explosive |
< 10^4 |
< 0.1 |
0 |
small |
10^4 to 10^6 |
0.1 to 1.0 |
1 |
moderate |
> 10^6 to 10^7 |
> 1.0 to 5.0 |
2 |
moderate to large |
> 10^7 to 10^8 |
3.0 – 15.0 |
3 |
large |
> 10^8 to 10^9 |
10 – 25 |
4 |
very large |
> 10^9 to 10^10 |
> 25 |
5 |
very large |
> 10^10 to 10^11 |
> 25 |
6 |
very large |
> 10^11 to 10^12 |
> 25 |
7 |
very large |
> 10^12 |
> 25 |
8 |
VEI |
Qualitative |
Tsuya Class |
0 |
gentle, effusive |
I |
1 |
gentle, effusive |
II – III |
2 |
explosive |
IV |
3 |
explosive |
V |
4 |
cataclysmic, paroxysmal, colossal |
VI |
5 |
cataclysmic, paroxysmal, colossal |
VII |
6 |
cataclysmic, paroxysmal, colossal |
VIII |
7 |
cataclysmic, paroxysmal, colossal |
IX |
8 |
cataclysmic, paroxysmal, colossal |
IX |
Descriptive Term |
VEI |
Hawaiian |
0 to 1 |
Stombolian |
1 to 2 |
Volcanian |
2 to 4 |
Plinian |
4 to 5+ |
Ultraplinian |
5 to 8 |
Limitations:
• The VEI assumes that the magnitude and intensity of eruptions are related in some way and that a single number can fully describe the size of an eruption. The VEI may work for some eruptions, but for many others the magnitude and intensity scales provide more useful information.
Specialty: Emergency Medicine, Critical Care
ICD-10: ,