Water Waves Generated by Landslides

The problem of water waves generated by landslides is studied by considering two distinct types of landslide; vertical and horizontal. The vertical landslide is studied by assuming that the landslide is modeled by a two-dimensional box falling vertically. A horizontal landslide is one which enters and moves through the water horizontally and is modeled analytically by a two-dimensional wall which moves into the fluid domain. Theoretical solutions are obtained assuming that the geometric and dynamic parameters of the problem are known. Graphs are presented for motion with constant velocity. For the vertical landslide problem, experiments were performed to verify this theory and the results compare very favorably in the region where linearized theory is valid. An approximate method is developed to find the amplitude of the largest wave in the nonlinear region by utilizing the solutions obtained from linear theory for vertical landslides. This approximate method is then applied to the Lituya Bay, Alaska landslide of July 9, 1958 in order to estimate the largest wave.