Interesting link - and conclusion:
You can clearly see that the Tohokou aftershock activity and the earthquake triggering effects have significantly increased the total number of earthquakes worldwide. This shows nicely that earthquakes do not occur randomly in time (as the probabilistic Poissonian model assumes). This is why in probabilistic seismic hazard assessment the aftershock activity is extracted from the catalogues, but this introduces an additional source of uncertainty.

• Animation of the 2011 worldwide seismicity