Forest fire model could explain earthquake distribution

Science : Statistically, the frequency of earthquakes decreases with increasing earthquake size in proportion to the size raised to the power of around −1.65. In a paper published last week in Physical Review Letters, Eduardo Jagla of Argentina’s National Atomic Energy Commission in Bariloche has developed a model that can not only account for the value of the power law’s exponent, but can also accommodate large infrequent earthquakes and small aftershocks. Jagla based his approach on the Drössel–Schwabl model of wildfire propagation, in which trees grow in size and density until a lightning strike causes one tree to ignite neighboring trees. When applied to earthquakes, a seismic fault plays the role of the forest and zones of stress play the role of the trees. Whether Jagla’s model can predict earthquake activity remains to be seen.