Abstract:
The Balkans, including Bulgaria, is one of the most seismogenic zones in Europe. The relatively small depth of the hypocentres of earthquakes – up to 60-70 km, could greatly increase the effects on the ground surface. In conditions of relatively high population density and high urban constructions, even a moderate magnitude earthquake could lead to increased unfavourable consequences – destruction and human loses.
The global impacts of atmospheric and oceanic processes, tidal deformations of the earth’s crust, the global seismic process, as well as the less well-studied processes in the Earth’s crust, are associated with accumulation and slow dissipation of tectonic energy in the lithosphere. These processes are the “participants” in the formation of the random process, during which study, the traditional apparatus of spectral analysis proves to be less effective.
The usage of fractal analysis for decipher the structure of seismic noise is a good enough alternative. Since the early 1990s, the method is used in both: turbulence analysis and in financial and medical time series studies.
The development of new methods for earthquake forecasting based on data from geophysical and, in particular, seismic monitoring, is one of the priority goals of Earth science. Seismic records of twenty-three Balkan Peninsula stations were analyzed, at distances of 1 to 500 km far from the earthquake on 23.09.2016, 27.12.2016 and 28.10.2018 with magnitude more 5.5 in seismic zone Vranchea. For the analysis, the Lubusin method was used for fractal analysis of scalar time series.
A scientific goal is to detect common signals ignoring the “individual” behavior of the elements of the monitoring systems.