Comment on "Diffusion of epicenters of earthquake aftershocks, Omori's law, and generalized continuous-time random walk models".

Modeling of earthquake sequences using an epidemic-type aftershock sequence model by Phys. Rev. E 66, 061104 (2002)] has led these authors to conclude that previous analyses of apparent earthquake diffusions were flawed. We show here that diffusion analyses based on spatiotemporal correlation measures for earthquake populations are an appropriate method for capturing the space-time coupling present in earthquake triggering processes.