Estimations of the Spatial Distributions of Probabilities of the Occurrence of Destructive Earthquakes in the Sichuan Area Based on the Markov Chain–Linear Kriging Coupling Model

Abstract

An earthquake is one of the most serious natural disasters to human beings. The damage from destructive earthquakes is enormous, and the predictions and estimations of earthquakes are urgent challenges in global science fields. In view of the shortcomings of the Markov chain model and the kriging methods in the estimation of the probabilities of the occurrence of earthquakes, the Markov chain–linear kriging coupling model has been established. The model has been applied to estimate the spatial distribution of probabilities of the occurrence of destructive earthquakes of Ms4.5 and Ms6.0 and above in the Sichuan area. According to the estimations of this model, the maximum probabilities of the occurrence of earthquakes of Ms4.5 and Ms6.0 and above in the Changning area of Yibin are 9.59% and 0.46%, respectively, which are close to the frequencies of occurrences of earthquakes of corresponding magnitude in the series of earthquakes that occurred in June 2019 in the region. The validation indicates that the average standard errors of this model for estimating the probabilities of the occurrence of earthquakes of Ms4.5 and Ms6.0 and above are 4.96% and 0.81%, respectively, which are lower than the probability kriging, and the estimation of this model highlighted the high value region of the probabilities.