Lateral spreading and flooding along the Iskenderun coast in the 2023 Kahramanmaras earthquake sequence

抄録

The 2023 Kahramanmaras earthquake sequence produced extensive liquefaction-induced ground deformations along the infilled shoreline of the port city of Iskenderun, Turkiye. Observed liquefaction effects included ground settlement, seaward lateral spreading, and failures along a rubble mound seawall lining the coast. These effects, among other factors, likely contributed to ongoing flooding in Iskenderun during moderate storm and high tide events following the earthquakes. The Geotechnical Extreme Events Reconnaissance (GEER) team collected detailed observations and measurements of selected sites affected by liquefaction. This paper presents lateral spreading, ground settlement, and flooding observations in Iskenderun, which suggest widespread movements of the coastline relative to the current sea level. The Dogan restaurant case history is described in detail, where earthquake ground deformations and subsequent flooding damaged a dining patio, seawall, and nearby park facilities. Insights from these observations suggest a need to better understand multi-hazard liquefaction and flood consequences to enhance the resilience of coastal cities.