Modeling of R-wave Dispersion Curve by Using Fast Delta Matrix Method

This paper is based on computation of fundamental mode Rayleigh wave (R-wave) dispersion curve depending on layered earth model by using fast delta matrix method. In addition, this paper indicates the changes in the dispersion curve and phase velocity according to the model parameters, thickness, density, P and S-wave velocity. In this study, we introduced the mathematical solution of the fast delta matrix method which computes free mode dispersion of a layered earth model. We modelled dispersion curves for two earth model and figured out only the fundamental mode. First, we calculated dispersion curves for by increasing each parameter by 25% for a six layered earth model. Secondly, we examined changing in the thicknesses, densities, P and S-wave velocities for a two layered model. Result showed that variation in S-wave velocities has an important effect on R-wave phase velocities when it is compared with other effects of model parameters. However, this doesn’t mean that other parameters are not affective. When individual changing of the parameters examined, it is seen that all parameters have a role in changes of phase velocity and dispersion curve according to the frequency range.