| dc.description.abstract | This study aims to establish a seismogenic source model for probabilistic seismic hazard assessment (PSHA) for Taiwan, which is divided into shallow area sources, seismogenic structure sources, and subduction zone sources. The subduction zone sources are further categorized into interface and intraslab sources. The study redefines the region of shallow area sources, integrates seven catalogs and considers events from 1900 to 2022. After removing foreshocks and aftershocks using three different de-clustered methods, seismic activity rates for each region were calculated. The model incorporates updated inland seismogenic structures and newly identified offshore structures to compute their recurrence intervals. For some structures, multiple structures rupture and time-dependent seismic probability model, the Brownian Passage Time model, are considered to evaluate time-dependent rupture probabilities. The geometry and corresponding parameters of the subduction zone interface sources are based on the trench lines and the slip rates of TWSSHAC Level 3 Seismic Source Characterization model, and recurrence intervals are calculated using established plate geometries from previous studies. For subduction zone intraslab sources, a 3D plate model assuming a thickness of 50 km is used. The regions are redefined based on earthquake distribution, and seismic activity rates for each region are calculated. After considering uncertainties in earthquake magnitudes and long-term slip rates for seismogenic structures and subduction zone interface sources, combined with ground motion prediction equations and site parameters, seismic hazard assessments were conducted. Results indicate that southern Taiwan exhibits the highest ground motion in the peak ground acceleration (PGA) hazard map, while Hualien has the lowest exceedance probability for most PGA and spectral acceleration with a period of 0.3 second. Hualien also shows a higher likelihood of experiencing similar levels of ground motion compared to other regions. Disaggregation analysis reveals that subduction zones contribute minimally to the seismic hazard in terms of PGA but have a more significant impact on long-period spectral accelerations. This is particularly evident in Taipei, New Taipei, Tainan, and Kaohsiung, suggesting that these regions should pay special attention to the impact of earthquakes on high-rise buildings. By developing a probabilistic seismic source model based on new data to reflect recent research, the results of this study will aid in future seismic risk analyses and the implementation of disaster prevention strategies by public authorities. Applications include large-scale earthquake scenario simulations and earthquake disaster evacuation and rescue drills. | en_US |