Numerical modeling of the reflection coefficients for the plane sound wavereflection from a layered elastic bottom

The matrix method and its numerical realization are considered in calculati ng the complex reflection coefficients and refraction indices of plane soun d waves for geoacoustic models of the ocean bottom in the Form of homogeneo us elastic (liquid) absorbing layers overlying an elastic halfspace. In cal culating the reflection coefficients at high frequencies or in the presence of a large numbers of sedimentary layers, a passage from the Thomson-Haske ll matrix approach to the Dunkin-Thrower computational scheme is performed. The results of test calculations are presented. With the aim of developing resonance methods for the reconstruction of the parameters of layered elas tic media, the behavior of the frequency-angular dependences of the reflect ion coefficient are studied for various geoacoustic bottom models. The stru cture of the angular and frequency resonances of the reflection coefficient s is revealed. The dependence of the structure (the position, width, and am plitude) of two types of resonances on the parameters of the layered bottom is considered. (C) 2000 MAIK "Naulia/Interperiodica".