The Jales gold mine, in Portugal, operated until 1993, with the works stretching over 4 to 5 km and reaching a depth of 120 m. Geoelectric exploration to detect underground cavities resulting from subsidence and collapse of Jales mine galleries was performed for EDM  in the context of the environmental remediation of the mining area. CONVERGE! carried out several electrical resistivity tomography profiles that allowed to detect areas where the collapse of the galleries was most significant.