Computing the Response of Multi‐Component Induction Logging in Layered Anisotropic Formation by the Recursive Matrix Method with Magnetic‐Current‐Source Dyadic Green's Function

Abstract

Abstract A recursive matrix method is adopted to compute the magnetic‐current‐source dyadic Green's function in anisotropic media. The response of multi‐component induction logging in layered and deviated anisotropic formation is simulated by using the obtained dyadic Green's function. The influence of coil spacing, bed thickness, deviation angle and shoulder bed on the response is analyzed. The computation result shows that the changing pattern of coplanar apparent conductivity is more complex than coaxial apparent conductivity and can not reflect the formation's real conductivity. The coaxial apparent conductivity decreases with the increasing deviation angle in anisotropic formation, while the coplanar apparent conductivity increases with growing deviation angle. The tool's vertical resolution and the influence of shoulder bed's anisotropy on the tool's response in the target formation bed are determined by coil spacing. The influence of the shoulder bed's anisotropy on the response in high‐conductivity target formation is bigger than that in high‐resistivity target formation.