Abstract
The method for recognition and monitoring of ULF electrotelluric signals with steep fronts is presented. The method is based on the multicomponent measurements of the geoelectric field and recognition of the clusters of signals using the data of spatial-polarization filtering. This detects the local sources of the signals associated with the variation of mode of deformation of the medium. The method was applied to the study of geoelectric sources associated with aftershocks of the Racha-Djava earthquake. The field observations show with a fair degree of confidence that these signals are generated by a small number of local zones in the vicinity of the observer (at a range of tens-hundreds meters). The spatial distribution and the dynamic properties of the local sources are described. The analysis of observations leads to the conclusion that the dynamics of the local sources of ULF signals with steep fronts may be considered possible electrotelluric precursors of the earthquakes. Consideration is given to the feasibility of the well-known VAN method for earthquake prediction. The overall methodological aspects of the current studies of the electrotelluric precursors of the earthquakes are discussed.
Highlights
The study of Ultra Low Frequency (ULF) geoelectric signals with steep fronts is popular at the moment
The study of local sources of ULF geoelectric signals with steep fronts measured by two pairs of two orthogonal measuring lines
The method is based on the idea of spatial filtration taking into account the polarization properties of the signals, and recognition of the clusters of the signal sources using the data of spatial-polarization filtering. These procedures allow us to detect the specific anomalies of the ULF geoelectric field against a noise background through the control of intensification and synchronization of the cluster emissions
Summary
The study of Ultra Low Frequency (ULF) geoelectric signals with steep fronts is popular at the moment. In our opinion the general cause of the paradox is mainly the local origin of precursory signals with steep fronts and unsuitability of existing techniques of measurements, data processing and prediction of earthquakes for such kind of signals. The distribution of relative amplitudes of signals at the points of measurement produced by the cluster centers of sources for the three independent intervals of monitoring.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
