Increasing the resolution of electromagnetic tools for resistivity evaluations in near borehole zones

摘要

A tool for performing electromagnetic measurements within a borehole includes a transmitter including a coil having N-turns wound coaxially around a long metallic mandrel and a receiver including a coil having a one-turn receiving loop wound coaxially around the mandrel; wherein the transmitter is adapted for providing a current I of a predetermined frequency f of a maximum intensity in a predetermined part of a near borehole zone; and wherein the receiver is disposed a distance L from the transmitter and adapted for receiving a signal from the transmitter. A method for use of the tool is provided.