Abstract: City subway construction can cause great impacts on the surrounding elect ro-magnetic observations, and geoelectrical resistivity field must have a distance above 25 kil-ometers to avoid subway interferrence,causing a lot of trouble to the relocation of field. In this paper, effects of the Nanjing subway is tested, the new arrangement of electrodes scheme is put forward to the relocation of Jiangning site. This scheme adopts shortening the current distance to suppress the subway interference, using deeply buried electrode to guarantee the detection depth and suppress the surface effect. The new ideas are provided to choose the electric field which has been affected by subway while not taking the avoiding measures.

Key words: Electromagnetic observation, Resistivity, Method of elect rodes scheme, Jiangning field site