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На примере сейсмического события, обладающего магнитудой и механизмом глубокофокусного землетрясения у берегов Фиджи 19.08.2018, теоретически исследована связь параметров источника цунами с глубиной землетрясения. Показано, что сильные глубокофокусные землетрясения способны создавать обширные области косейсмических деформаций дна, размер которых сопоставим с баротропным радиусом деформации Россби. Волны цунами, формируемые такими источниками, обладают необычайно большой длиной и поэтому подвержены влиянию силы Кориолиса. Это влияние может варьироваться от существенного в высоких широтах до малозначительного в приэкваториальных районах. Методом численного моделирования исследовано влияние силы Кориолиса на слабые волны цунами, вызванные Фиджийским землетрясением 2018 г., Using the example of a seismic event with the same magnitude and mechanism as for the 2018 Fiji deep-focus earthquake the relationship between the parameters of a tsunami source and the depth of an earthquake was theoretically investigated. It is shown that strong deep-focus earthquakes are capable of creating extensive areas of co-seismic deformations for the ocean bottom, the size of which is comparable to the barotropic Rossby deformation radius. Tsunami waves generated by such sources have an unusually large length, and therefore they are subject to the influence of the Coriolis force. The influence of the Coriolis force on the weak tsunami waves caused by the 2018 Fiji earthquake has been studied by numerical simulation. It was found that for a virtual sea-level station located to the south of the source at latitude of 40S, the amplitude of the leading tsunami wave under the influence of the Coriolis force decreased by ≈ 30%. For virtual stations located at the equator or at latitude of 20S, taking into account the Coriolis force changes the amplitude of the waves by no more than 10%. For stations located in the equatorial zone, the effect of delaying of the manifestation of differences in sea-level fluctuations, calculated with and without Coriolis force, as compared with the entry of the leading tsunami wave was discovered. A physical interpretation of the observed delay effect is proposed., №1(24) (2019)