Cable for prospecting

A cable for prospecting, said cable including a core of conductor wires (3) surrounded by insulating material (4) and by armour (7, 8) formed by at least one layer of helically wound steel wires. It includes, from its center to its periphery, inside the armour, an axial monofilament (2) made of a polymer that withstands high temperatures, said monofilament forming the insulation of an inner conductor (1), an outer conductor (5) and a sheath (6) made of a thermoplastic substance that withstands high temperatures, said inner conductor serving a different electrical function than said core of conductor wires.