Distribution research of recurrence interval for moderate-strong earthquake in the mainland of China

Probability distribution of earthquake recurrence interval is the foundation of calculating the occurrence probability of earthquake. Based on the historical earthquake catalog data, the normalized local recurrence intervals of moderate-strong earthquake in the mainland of China are statistically analyzed. It is found that earthquake activity has both periodic and clustering characteristics. We construct a hybrid distribution model using lognormal distribution and exponential distribution, and the optimal parameters of the hybrid distribution model are estimated through least square method. The error analysis demonstrates that the hybrid probability distribution model is more consistent with the characteristic of moderate-strong earthquake activity in the mainland of China.