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.
 
 
Highlights
Using fractal analysis is an excellent alternative method for decode the seismic noise structure
The study of the Hurst (H) parameter (Oynakov, E. et al 2019) shows that for the stations, located in the epicenter zone, it increases about 3-4 days before the earthquake and for the stations located at a longer distance it increases about 2-4 days before the earthquake
The spectral timing diagrams of the coherent behavior of the seismic signal for all stations evaluated in a time window of 7200 minutes (5 days) with an offset of 60 minutes (1 hour) for the interval 06.10 – 28.10.2018 indicate the synchronization of the stations in the epicenter area from 9 to 3 days before the earthquake
Summary
Using fractal analysis is an excellent alternative method for decode the seismic noise structure. 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. Aleksandrova 2019 is shown that the transition from an analysis of baseline low-frequency microseismic data to the study of the variations of the multifractal statistical parameters allows detecting hidden effects of synchronization before the earthquake of 28.10.2018 in the Vrancea region. The spectral timing diagrams of the coherent behavior of the seismic signal for all stations evaluated in a time window of 7200 minutes (5 days) with an offset of 60 minutes (1 hour) for the interval 06.10 – 28.10.2018 indicate the synchronization of the stations in the epicenter area from 9 to 3 days before the earthquake. The synchronization of the seismic signal starts 9 days before the earthquake
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
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 call
