| Summary: | The Aegean is the most seismically active and tectonically complex region in Europe. Damaging earthquakes have occurred here throughout recorded history, often resulting in considerable loss of life. The Monte Carlo method of probabilistic seismic hazard analysis (PSHA) is used to determine the level of ground motion likely to be exceeded in a given time period. Multiple random simulations of seismicity are generated to calculate, directly, the ground motion for a given site. The three fundamental components of PSHA are considered: seismic source model, magnitude recurrence model and ground motion attenuation model. Initial analysis of the earthquake catalogue indicates that a doubly-truncated Gutenberg-Richter recurrence relation is an appropriate recurrence model for the Aegean. A novel seismic source model is presented, developed by interpretation of Aegean seismotectonics. The K-means cluster analysis algorithmis introduced as newand objectivemeans of partitioning seismicity and seismogenic faults to achieve of source zone delineation. Partitions of the seismicity containing 20 to 30 earthquake clusters emerge as the most appropriate for modelling seismicity in the Aegean. The 27 and 29 cluster K-means source models are integrated into the seismic hazard analysis alongside existing source models. Attenuation models are reviewed, (including European, Greek and global Next Generation Attenuation models) and their suitability for the Aegean region qualitatively and quantitatively assessed. Seismic hazard maps are produced and site-specific seismic hazard analyses undertaken for 8 selected cities across the Aegean. Epistemic uncertainty is qualitatively assessed by consideration of different source and attenuation models, before being integrated into the PSHA via the Monte Carlo technique. Further extensions to this method (fault and site characterization and aftershock simulation) are presented and their impact on the PSHA assessed. Fault and site characterization appear to have a significant impact on the outcome of the seismic hazard analysis.
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