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The generation, propagation and inundation for a probabilistic near-field tsunami hazards assessment (PTHA) at the Cascadia Subduction Zone (CSZ) are analyzed numerically. For the tsunami hazard assessment, a new method is presented to characterize the randomness of the fault slip in terms of the moment magnitude, peak slip location, and a fault slip shape distribution parameterized as a Gaussian distribution. For the tsunami inundation resulting from the seismic event, five tsunami intensity measures (IMs) are estimated: (1) the maximum inundation depth, h Max , (2) the maximum velocity, V Max , (3) the maximum momentum flux, M Max , (4) the initial arrival time exceeding a 1 m inundation depth, T A , and (5) the duration exceeding a 1 m inundation depth, T h , and presented in the form of annual exceedance probabilities conditioned on a full-rupture CSZ event. The IMs are generally observed to increase as the moment magnitude increases, as the proximity of the peak slip becomes closer to the study area, and as the distribution of fault shape narrows. Among the IMs, the arrival time (T A) shows a relatively weak sensitivity to the aleatory uncertainty while the other IMs show significant sensitivity, especially M Max. It is observed at the shoreline that M Max increases by an order of magnitude from the 500-year to the 1,000year event, while h Max increases by a factor of 3, and T A decreases by only factor of 0.05. The intensity of IMs generally decreases inland, but there are also varying dependencies on bathymetry. For example, a

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Annual exceedance probabilities of the maximum tsunami inundation depth, h Max , and momentum flux, M Max , conditional on a full-rupture event of the Cascadia Subduction Zone (CSZ) were used to estimate the probability of building damage using a fragility analysis at Seaside, Oregon. Tax lot data, Google Street View, and field reconnaissance surveys were used to classify the buildings in Seaside and to correlate building typologies with existing fragility curves according to the construction material, number of stories, and building seismic design level based on the date of construction. A fragility analysis was used to estimate the damage probability of buildings for 500-, 1,000-, and 2,500-year exceedance probabilities conditioned on a full-rupture CSZ event. Finally, the sensitivity of building damage was estimated for both the aleatory and epistemic uncertainties involved in the process of damage estimation. Probable damage estimates from the fragility curves based on h Max and on M Max both generally show higher damage probability for structures that are wooden and closer to the shoreline than those that are reinforced concrete (RC) and further landward of the shoreline. However, a relatively high and somewhat unrealistic damage probability was found at the river and creek region from the fragility curve analysis using h Max. Within 500 m from the shoreline, wood structure damage shows significant sensitivity to the aleatory uncertainty of the tsunami generation from the CSZ event. On the other hand, RC structure damage showed equal sensitivity to the aleatory uncertainty of the tsunami generation as well as the epistemic uncertainties due to the numerical modeling of the tsunami inundation (friction), the building classification (material and date of construction), and the type of fragility curves (depth or momentum flux type curves). Further from the shoreline, the wood structures showed similar aleatory and epistemic uncertainties, qualitatively similar to the RC structure sensitivity closer to the shoreline.