Fault Based Tsunami Generation and Hazard Analysis: A Probabilistic Study for Aegean Coasts of Türkiye

The coasts of Türkiye are vulnerable to tsunami hazards due to the intensive use of coastal areas and the activity of faults in the surrounding seas. The Samos-İzmir earthquake occurred on October 30, 2020, followed by a tsunami that affected the Sığacık Bay revealed this fact once again, demonstrating the importance of accurately modeling the tsunami hazard across the country. Probabilistic Tsunami Hazard Assessment (PTHA) results for various coastal engineering parameters (i.e., tsunami wave height, tsunami inundation distance) constitute one of the essential inputs of performance-based tsunami risk analysis. The TSUMAPS-NEAM project that ended in 2018 was one of the studies following the probabilistic approach for the Northeast Atlantic, Mediterranean, and connected seas (Basili et al. 2021). The primary objective of this study which is constructed within the TUBITAK (Scientific and Technological Research Council of Turkey) funded 121M750 project, is to develop a comprehensive probabilistic tsunami hazard analysis framework in which the uncertainties regarding active faults that can generate tsunamis for our country's Aegean Sea coasts are addressed fully. For this purpose, a holistic seismotectonic database has been created by compiling catalogs of active faults that can generate tsunamis in the Aegean Sea and its surroundings, important fault parameters, earthquake and focal mechanism solutions from national and international sources. The compiled database is utilized to determine possible tsunami source scenarios and model the epistemic and aleatory uncertainties in these scenarios. In this regard, a complete probabilistic set of tsunami source scenarios that have not been included in previous studies is being developed, and the near-shore tsunami wave height estimations will be determined by performing high-resolution tsunami simulations for each scenario. Considering the lack of hazard-based tsunami assessment for the coasts of the Aegean Sea, the near-shore tsunami wave height hazard curves to be obtained as a result of the project are of great importance in determining the effects of possible tsunamis and assessing the tsunami risk.

Acknowledgement: This study is supported by TUBITAK 1001-Grant Project No: 121M750.