A modelling study on tsunami propagation in the Red Sea: Historical events, potential hazards and spectral analysis

Abstract

This work reports results from numerical simulations of the tsunami triggered by 1995 Nuweiba earthquake, in the Gulf of Aqaba, which are consistent with the available observations. A series of 12 potential tsunamigenic sources are then considered in the Red Sea: related to major submarine earthquakes; volcanism (entry of pyroclastic flows and caldera collapse) and submarine landslides. Numerical simulations have been carried out to solve the spatial distribution of maximum amplitudes of water elevations and currents, and the flooded coastal areas. The peak energy in the simulated events range from 1 kt (1 kt=4.18×1012 J) up to 1.5 Mt, and global flood volumes range from 0.005 km3 up to 4.4 km3. A linear correlation can be established between both magnitudes for the set of tsunamis triggered by earthquakes up to 300 kt. Tsunamis triggered by submarine landslides show high directionality, but they occur in deep waters and showed lower impacts on the shoreline, as those triggered by volcanism. A FFT analysis shows that in this basin, tsunamis excite low frequency constituents which can be interpreted as eigenmodes. High frequencies are excited only in the proximity of the source, and the Gulf of Suez excites only those eigenmodes close to the ones of the main basin.