Patent ID: 9671517
Date: 2017-06-06
CPC Classifications: E21B,G01V

Claim:
1. A tool for imaging a formation through a substantially non-conductive medium, said formation traversed by a borehole, the tool comprising: at least two injection electrodes for injecting current through the substantially non-conductive medium and into the formation; one or more return electrodes for receiving current from the substantially non-conductive medium, the formation, or both, at least one of the injection electrodes being spaced at a distance from a borehole wall, the distance differing from one of the other injection electrodes, the return electrode, or both; and circuitry in communication with the spaced-apart electrodes for determining a complex impedance based on the received current, determining a phase angle of the complex impedance, determining an orthogonal component comprising a component of the complex impedance that is orthogonal to the phase angle, the orthogonal component insensitive to the non-conductive medium and sensitive to the formation, and processing the orthogonal component to image the formation apart from a parallel component comprising a component of the complex impedance that is parallel to the phase angle, the parallel component sensitive substantially to the non-conductive medium.