The magnitude and creepex correlation parameter as an indicator of the environmental restructuring in preparation for the strongest earthquakes

According to the data of the global and regional earthquake catalogs, the dynamics of the environment on the eve of strong (MS ≥ 6.2 for regions) and catastrophic (MS ≥ 8 for the whole world) earthquakes has been studied using the KCOR anomaly detection algorithm (the coefficient of paired correlation of the creepex Cr and the magnitude MS). A pattern of long-term anomalies has been established within the boundaries of the far-reaching zone of influence on the seismic focus preparation, the radius RF of which is calculated taking into account the stress distribution in elastoplastic environment. The seismic focus size is calculated from MS using the RC-2016 formula. The results of different calculation methods of KCOR and creepex Cr are compared. On both a global and regional scale, in the RF-vicinity, the scanning algorithm of the entire catalog revealed a pattern (in 100 % of cases) of significantly longer positive KCOR anomalies (from one and a half to nine years) before the strongest earthquakes of the catalogs when the classical creepex Cr0 = MS − mb is used in comparison with other methods. This may indicate the establishment of a special elastic-plastic state of the environment in the preparation RF-area of large earthquake foci.