Interwell tomography methods and systems employing a casing segment with at least one transmission crossover arrangement

An interwell tomography system that comprises:

• a downhole casing tubular deployed in a first borehole and having at least one transmission crossover arrangement, each transmission crossover arrangement having an adapter in communication with a coil antenna that encircles an exterior of the casing tubular;
• a conductive path, deployed inside the casing tubular, that extends from a surface interface to the at least one transmission crossover arrangement;
• a set of one or more antennas in a second borehole, wherein the set of one or more antennas and the least one transmission crossover arrangement obtain electromagnetic (EM) measurements for interwell tomography, and wherein obtaining the EM measurements involves conveying data or power between the at least one transmission crossover arrangement and the surface interface via the conductive path;
• and
• a processing unit that derives at least one characteristic of a region between the first and second boreholes based on the obtained EM measurements.