Time-dependent probabilistic seismic hazard assessment and its application to Hualien City, Taiwan

TitleTime-dependent probabilistic seismic hazard assessment and its application to Hualien City, Taiwan
Publication TypeJournal Article
Year of Publication2013
AuthorsChan C-H, Wu Y-M, Cheng C-T, Lin P-S, Wu Y-C
JournalNatural Hazards and Earth Systems Science
Date Published05/2013

Here, we propose a time-dependent probabilistic seismic hazard assessment and apply it to Hualien City, Tai- wan. A declustering catalog from 1940 to 2005 was used to build up a long-term seismicity rate model using a smooth- ing Kernel function. We also evaluated short-term seismic- ity rate perturbations according to the rate-and-state fric- tion model, and the Coulomb stress changes imparted by earthquakes from 2006 to 2010. We assessed both long-term and short-term probabilistic seismic hazards by considering ground motion prediction equations for crustal and subduc- tion earthquakes. The long-term seismic hazard in Hualien CitygaveaPGA(peakgroundacceleration)of0.46gfor the 2.1 ‰ annual exceedance probability. The result is simi- lar to the levels determined in previous studies. Seismic haz- ards were significantly elevated following the 2007 ML = 5.8 earthquake that occurred approximately 10 km from Hualien City. This work presents an assessment of a suitable mecha- nismfortime-dependentprobabilisticseismichazarddeter- minations using an updated earthquake catalog. Using minor model assumptions, our approach provides a suitable basis for rapid re-evaluations and will benefit decision-makers and public officials regarding seismic hazard mitigation.