Time-and space-dependent earthquake rupture simulation for Nankai-Tonankai Trough in Japan incorporating multivariate Bernoulli method and stochastic slip models
Abstract
In this thesis, a new segmented earthquake occurrence simulation method is developed and is applied to the Nankai-Tonankai megathrust earthquakes, which have historically caused significant damage to the coastal areas of Japan and have a large potential to occur in the next 50 years. For targeting the segmented rupture pattern in Nankai-Tonankai Trough, the simulation method incorporates the multivariate Bernoulli method, which models the rupture pattern by considering both spatial and temporal correlations of individual segments, and the stochastic slip modelling method that produces heterogeneous slip models corresponding to different rupture patterns. Furthermore, possible predominant factors that could affect the earthquake simulation, including the earthquake occurrence catalogs, interarrival time distributions and segmentation pattern, are examined through varying simulation settings. According to its application in seismic hazard assessment, the multivariate-stochastic hybrid method successfully captures the historical seismicity of the Nankai-Tonankai Trough, while emphasizing additional seismic features depending on the predominant factors.