Geoinformational criteria for distinguishing the quasi-linear chains of earthquake migration in epicentral fields of complex geometry and variable density of shocks distribution

Abstract

Within the framework of the basic model of migrating seismicity, the main geoinformation criteria for identifying quasi-linear chains of earthquakes in epicentral fields of complex geometry and variable density of shock distribution have been determined by numerical methods. The developed model is used to study the migrations of earthquake foci and identify zones of hidden seismically active faults: it provides statistical criteria for the presence of quasi-linear chains of seismicity migration and zones of hidden seismic faults in arrays of various volumes of seismological data as an excess at a given level of significance of the average numbers of chains of earthquakes, spatially temporal distribution of shocks. The established dependences of the average number of selected chains of random events on the sample size and site shape make it possible to reveal the presence of seismicity migration and zones of hidden faults under the given criteria of “significance”, “representativeness” and ISMA. The developed methods, implemented programs and patents lay the theoretical and practical basis for GIS technology for identifying hidden faults and studying the migrations of earthquake foci in the lithosphere of the Baikal rift system. Since the main laws governing the formation of the internal structure of continental fault zones and seismicity are determined by the fundamental properties of the progressive deformation of transgressive shearing realized within them and are uniform, the developed GIS technologies can be applied in other seismically active regions.