Patent ID: 8736271
Filing Date: 2014-05-27
Classification: G01V

Abstract:
1. A method for making resistivity measurements of a formation surrounding a borehole using a tool comprising first and second pairs of spaced antennas, the pairs being separated along a tool body, the method comprising: i) positioning the tool body in the borehole so that the first pair of antennas is at a predetermined location in the borehole; ii) operating one of the second pair of antennas to induce a current in the formation surrounding the borehole; iii) measuring the voltage created by operation of the antenna; iv) measuring axial currents on the body at the first pair of antennas; v) moving the tool body along the borehole so that the second pair of antennas is at the predetermined location; vi) operating both of the second pair of antennas to induce currents in the formation surrounding the borehole; vii) measuring the voltages created by operation of the antennas; viii) measuring the axial currents on the body at one of the first pair of antennas as a result of operation of the second pair of antennas; and ix) determining the resistivity of the formation using the voltage and current measurements obtained;