Abstract: In seismic hazard analysis computation, there is much uncertainty in the process of defining latent focal region and upper magnitude limit. This thesis adopted two-level partition and three-level partition of latent focal region to study uncertainty of latent focal region. We use unilateral normal distribution of upper magnitude limit instead of fixed one and analyze the results of seismic hazard analysis of this change and engineer meaning of it. The results show that replacing the two-level partition of latent focal region by three-level one can decrease seismic hazard in some areas. It is of important significance in choosing site near latent focal region and meanwhile, the project cost can be reduced. This change of upper magnitude limit makes seismic hazard reduced, which is useful for project with one hundred years utilization limit.

Key words: Latent focal region, Upper magnitude limit, Uncertainty, Seismic hazard