Joint 2D Inversion of Induction and Galvanic Borehole Sounding Data When Logging Hydrocarbon Reservoirs

This paper concentrates on improving the reliability of hydrocarbon saturation estimation while investigating oil and gas reservoirs. We base on algorithms for multidimensional numerical simulation and inversion, as well as utilize a complex of induction and galvanic borehole sounding signals. We have developed software for joint numerical inversion of induction and galvanic log data within a consistent axially symmetric earth model. There is no need in depth matching since all the logs are recorded during one round-trip operation. We have reconstructed the spatial resistivity distribution around the borehole, taking into account enclosing rocks and thin impermeable carbonate and clay interlayers. Due to applying the joint inversion, one significantly reduces the zone of ambiguity in the inverse geophysical problem.