Application of linear digital filtering algorithm for the computation of electromagnetic response of a vertical magnetic dipole over inhomogeneous earth models

A linear digital filter algorithm is applied to compute the electromagnetic (em) field response of a vertical magnetic dipole placed over the surface of an inhomogeneous earth model having linear variation of conductivity with depth. The problem is formulated for a multi-layer inhomogeneous earth model. The field components are derived for three layer transitional earth models with intermediate layer possessing linear variation of conductivity with depth. Results for the various field components, showing the effects of variation of transition layer thickness and conductivity contrast between the top and bottom layers are presented in the form of absolute-amplitude ratio of field components expressed as the function of numerical distance. The results depict characteristic dependence of the em response over conductivity inhomogeneity.