After a mainshock, aftershock rate decays as:
n(t) = K / (t + c)^p
where K is productivity (scales with mainshock magnitude via Bath's law),
c prevents singularity at t=0, and p ≈ 1 (empirically 0.9–1.4).
The ETAS (Epidemic-Type Aftershock Sequence) model allows each aftershock to
trigger its own sequence — explaining the fractal clustering of seismicity.
The map shows epicenters; distance from mainshock follows Omori spatial decay ~r⁻².
Click the map to manually place a mainshock.