Strike-slip fault-generated paleotsunamis in Lake İznik (NW Türkiye): Numerical modeling corroborated by coastal deposits

Abstract

Strike-slip faults in lacustrine environments present overlooked tsunamigenic potential. For the first time, we have reconstructed paleotsunamis triggered by strike-slip faulting with a dip-slip component that ruptured the lake floor. This study focuses on Lake Iznik (T & uuml;rkiye), located along the middle strand of the North Anatolian Fault (MNAF). We modeled tsunami generation, propagation, and inundation for the 121 CE (Mw similar to 7.3) and 1065 CE (Mw similar to 6.9) earthquakes using a coupled coseismic dislocation and hydrodynamic model. Simulated run-ups and inundation distances are validated against coastal tsunami deposits. Our results show maximum run-ups of similar to 3 m for the 121 CE event and similar to 1 m for the 1065 CE event, highlighting the tsunami hazard to the lakeshore. We also demonstrate that the tsunami generated during the 1065 CE event lacked sufficient wave height (<0.5 m) to damage the newly discovered submerged Byzantine basilica. These findings emphasize the need to integrate tsunami risk into seismic hazard assessments for lacustrine strike-slip fault zones.