CONSISTENT TREATMENT OF UNCERTAINTIES IN EARTHQUAKE HAZARD EVALUATION

Site-specific earthquake hazard evaluation typically consists of establishing the design earthquake characteristics at top of rock or rock-like material, and accounting for the effects of local soil response on the ground motions. This type of study requires input from the disciplines of geology, seismology, and geotechnical engineering. Established uncertainties are often accounted for in one discipline but are not considered when the existing results are utilized in connection with work in another discipline, giving the total study an unreliable hazard assessment. A probabilistic procedure for evaluation of site-specific earthquake hazard is described. The procedure treats the uncertainties in all steps of the study, such as earthquake source geometry and seismicity, ground motion attenuation, and local soil response, in a consistent mannner. An example application from an offshore site on the Norwegia-n Continental Shelf (NCS) is also presented