DETERMINATION OF FORMATION ANISOTROPY USING MULTI-FREQUENCY PROCESSING OF INDUCTION MEASUREMENTS WITH TRANSVERSE INDUCTION COILS

摘要

Skin-effect corrections are applied to measurements made by a transverse induction logging tool to give corrected measurements indicative of vertical conductivities of a formation. Data from a conventional induction logging tool (10) are inverted or focused to give an isotropic model of formation resistivity (301). A forward modeling is used to derive from the isotropic model measurements that would be expected with a transverse induction logging tool (303). Skin-effect corrections are applied to these expected measurements (305). The formation anisotropy is determined from the skin-effect corrected transverse induction logging measurements, the skin-effect corrected expected measurements and from the isotropic model conductivities (311).