Analysis of the main characteristics of tsunamis based on data from deep-ocean stations

A tsunami in the ocean, according to one idea, is a long wave with a practically unchanged period and a relatively slow attenuation. According to others, the dispersion affects the evolution of a tsunami, the wave period increases with time, and the amplitude attenuation is more rapid. This study investigates the transformation of tsunamis from source to coast, including the change in amplitude and duration of the head waves with distance. It is shown that the dispersion does affect the evolution of the tsunamis. The moment of dispersion manifestation depends not only on the magnitude of the earthquake that caused each tsunami, but also significantly on the depth of the ocean in the focal region. (paper)