RESEARCH ON THE FRACTAL STATISTICAL CHARACTERISTICS AS POSSIBLE PROGNOSTIC PARAMETERS FOR EARTHQUAKES, GENERATED IN THE SEISMIC ZONE OF VRANCEA, IN THE PERIOD BETWEEN 01.08.2016 AND 30.12.2016

E. Oynakov; D. Solakov; I. Aleksandrova

doi:10.31435/rsglobal_wos/31082019/6649

E. Oynakov National Institute of Geophysics, Geodesy, and Geography, Bulgarian Academy of Sciences
D. Solakov National Institute of Geophysics, Geodesy, and Geography, Bulgarian Academy of Sciences
I. Aleksandrova National Institute of Geophysics, Geodesy, and Geography, Bulgarian Academy of Sciences

DOI: https://doi.org/10.31435/rsglobal_wos/31082019/6649

Keywords: Fractal analysis, microseismic noise, prognostic earthquakes

Abstract

Using fractal analysis is an excellent alternative method for decode the seismic noise structure. Fractal analysis of microseismic noise could also be an appropriate method to detect earthquake indicators. The scientific goal is to detect standard signals, based on different earthquakes’ focal mechanisms, separating the "individual" behavior of the elements of the monitoring systems.
The method for describing low-frequency microseismic noise from the network of seismic stations in a seismically active region of the Vrancea used. Seismic records of twenty-three broadband stations were analyzed, situated at distances of 20 to 500 km from the Vrancea earthquakes whit magnitudes Mw=5.7 and Mw=5.6 on September 23 and December 27, 2016, respectively. The daily assessment values of three multifractal parameters (characteristics of the multifractal singularity spectra of the waveform) from each station used for the description.
The present paper is a continuation of previous work [Oynakov et al., 2019], where the effects of synchronization in the low-frequency microseismic field were found before the Vrancea earthquake with magnitude Mp=5.6 on October 28, 2019.
The study shows that the noise coherence measure increased for stations, closer to the epicenter. However, the question of the source of this coherence remains open.

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