Recurrence of Seismic Effects

Carrying out work on seismic hazard assessment and seismic impact forecasting requires a complex of actions, one of the components of which is seismological research. A component of the latter is the study of the seismic regime of the territory, including, first of all, the study of earthquake recurrence law—the relationship between the number of earthquakes and the parameter that in one way or another characterizes the greatness of the seismic event. Usually, the magnitude of the earthquake or the energy class are chosen as such a parameter. However, the greatness of an earthquake can also be classified by the effect of seismic impacts. They can be characterized by various quantitative parameters of seismic ground motion—energy, kinematic characteristics, as well as intensity—an assessment of the strength of shaking on the Earth’s surface at the observation point. The last parameter describes the seismic effect of an earthquake. It is the final expression of the processes of generation and propagation of vibrations during an earthquake. The method of assessing seismic hazard using this characteristic of seismic events does not require knowledge of the location of earthquake sources and their characteristics: magnitudes, focal mechanisms, and source depths. In addition, in this case, there is no need for estimates of seismic treatments attenuation with distance. All this leads to an increase in the accuracy of predictive estimates of seismic hazard. In this study, using the example of the Greater Sochi region, the law of earthquake intensity recurrence is established. The problem of increasing the accuracy of seismic hazard assessments and seismic impact forecasts by studying the recurrence of various parameters of seismic ground motion is discussed.