On the possibility of seismic rogue waves in very soft soils

Liquid wave studies have shown that under certain constructive interference conditions, an abnormal size wave could be generated at a specific point. This type of wave, described long ago in the literature, was named 'Draupner Wave' in 1995. It was the first rogue wave, more than ten meters high, to be detected by a measuring instrument, occurring at the Draupner platform in the North Sea off the coast of Norway. For very soft and thick soils in continental sedimentary basin, with high water content, low shear wave velocity and wave bouncing effects on the edges of the basin, one can question the theoretical existence of such a type of freak waves that may have come unnoticed amongst surface seismic waves. This short communication presents recent observations and the conditions and limits of the analogy between gravity and seismic waves.