Estimating the Characteristics of Possible Land Slide-Tsunamis in Caspian Lake

Tsunami waves can be generated in any coastal area, including inland seas and large lakes. Although there exists enough information about the generation and propagation of tsunami in ocean environment, the assessment of such phenomenon in lakes with finite depth still suffers from the lack of theoretical work and sufficient measured data. The Caspian Sea is the largest lake in the world and has gone through different historical tsunami events. A numerical study for prediction of tsunami wave height time series for ten locations in the Caspian Sea is presented in this work. Unlike tsunamis generated by earthquakes, submarine landslide tsunamis generated in shallow waters are more destructive compared to those generated in deep water. This is due to the higher energy that can be converted from the slide to the water in shallow areas. Moreover, shallower waters are usually closer to the coasts and thus a shorter available distance exists for radial damping. The dispersion of short waves and also radial spreading decrease the far-field effects of landslide tsunamis in contrast to tsunamis of seismic origins. However, shorter waves are more prone to coastal amplification with higher local effects. The results of predictions are consistent with the previous finding reported in the literature indicating the possibility of tsunami occurrence in large lakes due to landslide which can affect the neighboring ports and area located particularly in the central and southern area of the Caspian Sea.