ALERT LEVEL
|
CRITERIA
|
INTERPRETATION
|
No alert | Background, quiet | No eruption in foreseeable future |
1 | Low level siesmic fumarol, other unrest | Magmatic, tectonic or hydrothermal disturbance; no eruption imminent |
2 | Moderate level of seismic, other unrest, with + evidence for involvement of magma |
(A) Probable Magmatic intrusion; could eventually lead to an eruption (B) If trend shows further decline, volcano may soon go to level 1 |
3 | Relatively high unrest incl. numerous b-type earthquakes, fumaroles, gas emission |
(A) If trend os one of increasing unrest, eruption is possible within 2 weeks (B) If trend is one of decreasing unrest, volcano may soon go to level 2 |
4 | Intense unrest incl. harmonic tremor and/or "long period" (=low frequency) earthquakes | Eruption possible within 24 hrs. |
5 | Eruption in progress | Eruption in progress |