On reproducibility of relative locations of recurrent earthquakes recovered at a single station

stable tendency of converging, from different sets of randomly seeded initial locations, to virtually indistinguishable final sets of locations, within each of the groups. To estimate the influence of ambient factors that might corrupt the completeness and accuracy of the sets of cross-correlation coefficients between the records at the stations located at longer epicentral distances the sets of the coefficients at the other three local network stations (Brid, Koroleve, and Nyzhnye Selyshche, at the distances of 29, 49 and 64 km respectively) were used to recover relative locations of the Mukacheve earthquakes. Versions of relative locations of the earthquakes recovered at all the four stations independently of each other turned out very similar to each other. Originality. It has been for the first time unequivocally established that similarity pattern between the waveforms of recurrent earthquakes at a station depends only weakly on the station’s azimuth and epicentral distance (within a range of up to 64 km), despite the noise and the distortions due to the differences in the medium structure and in the wave content of records at different epicentral distances, and uniquely determines relative location of the earthquakes. Practical significance. The algorithm for relocation of recurrent earthquakes based on similarity of their waveforms at a single station developed in the current work and the reproducibility of its results established in it enables significant improvements in the accuracy of relocation of the earthquakes with the use of the conventional techniques, and, in such a way, in the accuracy of tectonic interpretations of the relocation results, which is crucially important in estimation of seismic risk and seismic hazard.