The magnitude distribution law of characteristic earthquakes in Chinese mainland

Based on the fundamental assumption that the magnitude distribution of characteristic earthquakes obeys the normal distribution, the quantification research are carried out on the magnitude distribution of characteristic earthquakes. Given sparse magnitude data of large earthquakes recurrence in situ, this paper uses magnitude data converted by coseismic displacement data, and each magnitude obeys identical distribution after normalization, then the standard deviation σ which reflects the variability of the normalized magnitude can be got by statistic analysis. Using the approach proposed in this paper, analysis of coseismic displacements of 54 characteristic earthquakes in Chinese mainland suggests a generic value of σ=0.08, which provides an important basis for further studying occurrence probabilistic model of characteristic earthquakes.