In this short communication, a mathematical model for torsional wave propagation in a porous crustal layer lying over an anisotropic inhomogeneous half-space has been studied. This study reveals that the inhomogeneity in the half-space is assumed to be present in the directional rigidities and density. The anisotropy nature of the half-space is due to the presence of initial stress. Bessels functions are taken to solve the problem and the frequency equations governing the propagation of torsional waves are derived. It has been observed that there are three sets of torsional wave fronts and one shear wave front. Each set of torsional wave front has a pronounced effect on phase velocity, whereas shear wave front remains un-affected. Numerical treatment is applied to seek these effects on phase velocity of the existing waves and presented graphically. Graphical user interface has been developed using MATLAB to generalize the effect of the various parameters discussed.
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