APPLICATION OF DEAGGREGATION OF SPATIAL PROBABILISTIC SEISMIC HAZARD FOR DISASTER PREPAREDNESS

Abstract

For regional disaster prevention, it is important to understand the area of occurrence of strong
ground motion and its occurrence probability. The spatial probabilistic seismic hazard analysis (SPSHA)
proposed by the authors can provide this information. In SPSHA, the results are expressed as a relation between
the area where a given seismic intensity is generated and the exceedance probability. Results obtained from
such a probabilistic approach include the effects of various seismic sources. Therefore, to efficiently describe
an earthquake scenario for regional earthquake countermeasures, it is necessary to understand the impact of
each earthquake source. In this study, we propose a seismic hazard deaggregation for SPSHA, and present a
method for quantitatively understanding the earthquakes that affect the target region. As a practical application,
SPSHA is conducted for Kanagawa prefecture in Japan. We conducted seismic hazard deaggregation for whole
and sub-area, and discussed the differences in dominant earthquakes among areas and the use of such
information in disaster prevention.