A new method for direct measurement of a reservoir's macroanisotropy coefficient, exposed by a well, using a direct current probe, has been developed. The measuring device consists of pairs of current and measuring point electrodes arranged on a nonconductive housing. A mathematical model of the device has been developed and implemented for scenario calculations and determining the probe's design parameters. Key research methods employed include asymptotic analysis of boundary problem solutions and numerical modeling. The investigation has revealed the functional relationship between measured signals and the parameters of the geoelectric section. It has been found that the signals of tools with length ˜0.8 m are uniquely related to the coefficient of macroanisotropy of the medium and are practically independent of the longitudinal conductivity of the reservoir. Specific probe lengths have been established at which the device functions as a direct-action sensor detecting the presence of an electrical macro-anisotropy when passing the tool along a well. It has been demonstrated that the measured signal is linked to the macro-anisotropy coefficient through a simple function and can be calibrated to represent the values of this parameter. The possibility of the tool calibration inside the well at passage of a known interval of isotropic reservoir has been identified. The results of experimental testing of the design solutions on the physical model, confirmed by the data of numerical modeling, are presented.
