Geophysical processes and biosphere: article

Аnnotation: This paper selects and describes the procedures for assessing social and economic parameters of seismic risk using the example of the Angarsk City, Irkutsk region located at distances of 100–120 km from active seismic faults in the East Sayan Uplift and the Baikal Rift Zone, where earthquakes of magnitude М = 6.5–8.0 can occur. The relevance of this study follows from the required verification of the seismic hazard level of this rapidly developing region and the Declaration of the Sendai Framework Program for the Natural Disasters Risk Reduction for 2015–2030, calling for the improvement of risk assessment methodology and the implementation of measures to reduce it. The paper has for its goal reliable estimates of seismic risk parameters, which are necessary and sufficient in order to take a decision for risk reduction. The scientific novelty is due to the fact that for the first time in the study of a single city, the results of all stages of the study are presented, including the verified seismic hazard assessment, the vulnerability of elements at risk, as well as computation of various parameters of possible damage associated with the risk. For the first time, we did a joint analysis of all obtained variables. Methods of computer simulation were used to assess the risk parameters along with the «Extremum» GIS developed with the participation of the authors of this article. In addition to the methodological procedures, the article provides a justification for the parameters of possible and most hazardous seismic events. For the Angarsk City, the events have grades 8, 8, and 9 on the MMSK-86 intensity scale. The resulting values of the social and economic parameters of seismic risk proved to be the highest for the city districts of Baikalsk, Starobaikalsk, Kitoy, and Novy-4, which implies the need for implementation of special measures, including inspection and strengthening of the buildings.