Coulomb Stress Evolution and Seismic Hazard Analysis on the Xingtai Old Earthquake Region

Uing the PSGRN/PSCMP program, we calculated the Coulomb stress change on earthquake rupture surface based on the Burgers viscoelastic layer model, analyzed the comprehensive Coulomb failure stress change of all M_S≥6 earthquakes before each M_S≥6 earthquake in the Xingtai earthquake sequence, and explored the stress triggering relationship between strong earthquakes. The results show that, except for the March 26th magnitude 6.2 earthquake, all the earthquakes occurred in the stress triggering zone with increased Coulomb stress, and there were a good stress triggering relationship with the previous earthquakes of magnitude 6 and above. According to the coulomb stress evolution of the Xingtai earthquake sequences and the relationship between the activity of earthquakes of magnitude 5 and above and the old Xingtai earthquake seismic risk it is found that, the probability of the magnitude 5 or above earthquakes occurred in stress triggering zone is 71.9%. It shows that the seismic activities had a good correlation with the coulomb stress change in Xingtai old earthquake area. The coulomb stress dynamic evolution characteristics can be applied to the medium and long term prediction of earthquakes in this region, which can provide reference for the location of subsequent moderate and strong earthquakes.