对坑道内赤道偶极装置电阻率测深的可行性进行研究。分别在4个坑道面上布设测线,利用赤道偶极电阻率测深装置对坑道周围介质进行探测;采用有限单元法对坑道内赤道偶极装置电阻率测深进行正演计算。计算结果表明,对于单个地质体,坑道内任一断面的视电阻率异常均与其相邻的2个坑道面上的测深断面异常性质相反,而与坑道对面的测深断面异常性质相似;当坑道面外侧存在多个地质体时,各坑道面上的测深断面均不能将其有效区分。根据视电阻率测深断面异常形态和性质,对地质体的定位和定性解释的难度很大。采用赤道偶极装置在坑道中进行电阻率测深是不合适的。
Feasibility of dipole equatorial resistivity sounding in tunnel was discussed. Survey lines were arranged along four surfaces of tunnel and dipole equatorial-dipole system was utilized to detect medium around the tunnel. The dipole equatorial resistivity sounding in tunnel was calculated with the finite element method. The results show that the anomalous property of any section is contrary to those of two adjacent sections and similar to those of opposite sections for single geologic body. In the same way, the geologic bodies around tunnel cannot be distinguished from anomalous property of all apparent resistivity sections effectively. It is difficult to interpret location and electrical property of geologic bodies by studying shape and property of anomaly in sounding section maps. The sounding by using dipole equatorial array in tunnel is not appropriate.