Study of caspian Sea tsunami caused by a potential submarine landslide triggered due to seismic activity of the faulting system of the northern Iranian plateau

This study examines a significant accumulation of deposits on an abnormal slope in the southern Caspian Sea, which is believed to be a potential source of submarine landslides due to seismic activity in the faulting system of the northern Iranian plateau. A presumed earthquake M_w 7.7 originating from the Khazar Fault is identified as the triggering event for the landslide, and the induced landslide tsunami is simulated using the fully nonlinear and dispersive Boussinesq equations to assess the tsunami hazard along the southern coasts of the Caspian Sea. Considering the uncertainty in the dimensions of landslide, two scenarios are defined involving small and large submarine mass failures with volumes of 0.22 and 1.51 km³, respectively. The results indicate that the waves generated by the small landslide scenario reach approximately 1 m in height along the coastline, whereas waves as high as 8 m are observed during the large landslide tsunami. The tsunami waves diminish as they propagate along the coasts distant from the landslide location. However, in the case of a large probable landslide, the tsunami waves reach run-up heights of up to 4 m and inundate 300 m inland’ min the target area of the study (Anzali Port). The significant disparity between the two simulated scenarios highlights the importance of accurately estimating the potential locations and volumes of landslides, as well as the necessity of conducting further geological surveys to comprehensively evaluate tsunami hazards.