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On 23 February 2023, an Mw 6.8 earthquake struck the border of Tajikistan and Xinjiang China, the source mechanism remains controversial according to different seismic inversions. To better comprehend the source characteristics and the surface deformation pattern, we used the ascending and descending orbital Sentinel-1A SAR data to obtain the coseismic deformation of this earthquake based on the traditional two-pass differential interferometric synthetic aperture radar (InSAR). The source model is inverted from the InSAR coseismic deformation results. The possible Coulomb Failure Stress (CFS) transfer is analyzed based on the preferred source model. The results illustrate that the earthquake ruptured a blind left-lateral strike-slip fault of strike 28.1° with a maximum slip of 1.53 m and the total geodetic moment is 1.99 × 1019 N·m (Mw 6.83). The strike direction and the fault characteristics suggest the Seismogenic fault is a secondary fault of the Sarez–Karakul Fault System. The 2015 Mw 7.2 Sarez Earthquake plays a triggering role in the occurrence of the 2023 Tajikistan earthquake. Earthquake hazard on Sarez–Karakul Fault System and Sarez–Murghab Thrust System is enhanced due to the Coulomb stress loaded by the Tajikistan earthquake.

In this paper, we develop GA-BP algorithm by combining genetic algorithm (GA) with back propagation (BP) algorithm and establish genetic BP neural network. We also applied BP neural network based on BP algorithm and genetic BP neural network based on GA-BP algorithm to discriminate earthquakes and explosions. The obtained result shows that the discriminating performance of genetic BP network is slightly better than that of BP network.

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We try to give a quantitative and global discrimination function by studying mb/Ms data using Fisher method that is a kind of pattern recognition methods. The reliability of the function is also analyzed. The results show that this criterion works well and has a global feature, which can be used as first-level filtering criterions in event identification. The quantitative and linear discrimination function makes it possible to identify events automatically and achieve the goal to react the events quickly and effectively. Abstract Collection of Nuclear Inspection Technique (1). Beijing: Seismic Data and Information Center, State Seismological Bureau, 40.ACTA SEISMOLOGICA SINICA Vol. 18Criterion mdMs provides a comparison between two different parameters from one record of one event, which roughly ignores the effect of propagation medium features, but mainly display the character of hypocenter. Criterion mdMs is simple and practical, which can be used for preliminary event identification. In the paper, we have studied the discrimination efficiency of this criterion for the purpose to provide a reference for selecting the first-level filtering criterion for event identification.