Magnetic Permeability Sensor Array Prototype to Evaluate Reservoir Phase Permeability in situ Downhole.

A measurement system capable of in situ measurements of formation permeability is described. The measurement method relies upon imaging the distribution of magnetic permeability fluid injected into a wellbore system through mutual inductance measurements between pairs of coils and relating the change in distribution of this fluid over time to a direct measurement of formation phase permeability. Analysis of the mutual inductance measurement method shows a unique response to distributions of magnetic permeability for various coil spacings and insensitivity to other confounding electrical parameters. The lower bound of measurement variance for this system is modeled for a continuum of coil spacings and radii of investigation for a perturbation in magnetic permeability. [ABSTRACT FROM AUTHOR]