A comprehensive seismic risk assessment map of South Korea based on seismic, geotechnical, and social vulnerability

초록

At present, because it is not possible to predict earthquakes except the case of detecting seismic event a few seconds earlier by PS time difference, disaster preparedness is vital for the reduction of damages. The awareness about earthquakes has substantially increased after the occurrence of two > M-L 5 events in 2016 and 2017 in South Korea. This study presents the seismic risk assessment conducted for the entire country of South Korea. This assessment was performed using seismic, geotechnical, and social vulnerability indicators. The seismic vulnerability indicator was estimated using a probabilistic seismic hazard and fault-line density map that are directly related to the occurrence of earthquakes. The geotechnical vulnerability indicator was derived using bedrock depth data and extrapolation of digital elevation model data through geostatistical techniques. The seismic and geotechnical indicators were integrated based on the bedrock depth distribution. The social vulnerability indicator considered the distribution of relevant parameters, such as vulnerable people, old houses, and road information. These statistical data without spatial continuity were incorporated into a map using principal component analysis. A five-grade classification of risks presented by the seismic and geotechnical vulnerability map and the social vulnerability index map was developed to facilitate simultaneous assessment. A risk matrix was applied to the two maps to produce a comprehensive seismic risk assessment map of South Korea, in which the southeastern and northwestern regions of South Korea present a high seismic risk. The results of this study will serve toward seismic risk management and minimize seismic disaster damages in South Korea.

키워드