Spectral Magnitudes of the Sichuan,China,Earthquake of 12 May 2008,and Related Problems

The Sichuan earthquake is quantified on the basis of its spectral magnitudes of the P-and of the S-waves.The maximum spectral magnitudes of the two waves are seen to occur at different periods.The tectonophysical significance of the finding is discussed, and it is deduced from it that the S-wave energy radiated during the earthquake was drawn from unusually large volume, if compared to the volume corresponding to the P-waves.The spectral features of the body waves of the Sichuan earthquake are analysed on the background of the spectral features of a selection of worldwide earthquakes.As a result it is concluded that the Sichuan earthquake fits well into the features of the earthquakes in the surrounding regions.