| Caption: |
Increased seismic activity is a good indicator of a forthcoming volcanic eruption. As a dormant volcano reawakens, rising magma fractures rock above. At first the fracturing slowly increases the rate of seismic activity; then both the fracturing and seismic activity accelerate a few days prior to an eruption. (Modified after Kilburn, C. R. J., and Sammonds, P. R. 2005. Maximum warning times for imminent volcanic eruptions. Geophysical Research Letters 32:L24313, doi 10.1029/2005GL024184) |
