Patent ID: 7896073

Claim:
A method of imaging a resistivity property of a subsurface material, the method comprising: conveying a logging tool into a borehole, the logging tool having a plurality of unfocused measure electrodes; reducing a leakage of current from at least one of the plurality of measure electrodes to the subsurface material adjacent to another one of the plurality of measure electrodes by introducing a series impedance with the at least one of the plurality of measure electrodes and the other one of the plurality of measure electrodes; conveying a first measure current having a first frequency through a first the at least one of the plurality of measure electrodes; conveying a second measure current at the first frequency through a second the other one of the plurality of measure electrodes; and producing a 2-D image of the resistivity property of the subsurface material using a value of the first measure current and a value of the second measure current.