The synodic periods of planets in the solar system and synchronization of the timing of large earthquakes

We report the results from a search for statistically significant (at a significance level of <0.05) periodicities that synchronize the occurrence of large shallow (h ≤ 100 km) earthquakes in the eight world regions with the highest level of seismicity. The periodicities in question include the synodic periods of planets of the solar system (Mercury, Venus, Mars, and Jupiter), as well as the precession period of the lunar orbit. In five of the eight regions we have found statistically significant results for the period T ≈ 780 days, corresponding to the synodic period of Mars. The lunar cycle and the period of Mercury were significant in two regions. These results cannot be accounted for by invoking the disturbing influence of gravitational and tidal forces due to planets other than the Earth. The significant periodicities were used to develop a forecast (for the period 2004–2009) of the most probable time intervals for the occurrence of large earthquakes in four regions: Kamchatka, the South Kurils, northeastern Japan, and the Nankai trough.