Assessment of seismic hazard associated with the Meishan fault in Central Taiwan

• Published in: Bulletin of engineering geology and the environment Vol. 72; no. 2; pp. 249 - 256
• Main Authors: Wang, Jui-Pin, Huang, Duruo, Chang, Su-Chin
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.06.2013; Springer Nature B.V
• Subjects: Assessments; Cities; Earth and Environmental Science; Earth Sciences; Earthquake engineering; Earthquakes; Environmental risk; Equivalence; Fault lines; Faults; Foundations; Geoecology/Natural Processes; Geoengineering; Geological engineering; Geological surveys; Geology; Geotechnical Engineering & Applied Earth Sciences; Hazard mitigation; Hydraulics; Nature Conservation; Original Paper; Random variables; Seismic activity; Seismic hazard; Seismic phenomena; Uncertainty; Hong Kong China; China; Taiwan; China, People's Rep., Zhejiang Prov., Changxing Cty., Meishan; Uncertainty; Meishan fault in Central Taiwan; Seismic hazard; Probabilistic approach
• ISSN: 1435-9529; 1435-9537
• DOI: 10.1007/s10064-013-0471-x

According to the Central Geological Survey Taiwan (CGST), the Meishan fault in Central Taiwan, which induced a catastrophic earthquake in 1906, is considered capable of triggering equivalent events with a return period of 162 years. Therefore, as the next event is expected around 2070, the Meishan fault poses a high level of earthquake risk in Central Taiwan, especially for those cities and townships very close to the fault. However, the best-estimate return period (162 years) and earthquake magnitude (7.1 M L ) reported by the CGST must be subject to some uncertainty, because such an event is very unlikely to recur every 162 years. Therefore, this study carried out a series of seismic hazard assessments for three major cities close to the Meishan fault, with the uncertainty of the best-estimate information being determined using the Rosenblueth algorithm. The results show that for Chaiyi city, which the Meishan fault passes through, the probability of the current design value (i.e., PGA = 0.33 g) being exceeded by the earthquake motion induced by the Meishan fault in the next 50 years would be as high as 55 %. Therefore, further studies should be carried out to obtain a better understanding of the Meishan fault, to develop a robust hazard mitigation plan for nearby cities.