对低频井间电磁数据进行灵敏度分析的结果表明,对响应有贡献的区域为准椭球形,该椭球包括了震源点和接收点。最强的响应源于震源与接收的周围;但是我们只可能测到井间区的响应。在井间区以外,存在着反极性旁瓣。在具细长(二维)地质特性和频率递增的两种情况下,井间区对响应的贡献显著增 Sensitivity analysis of low-frequency crosswell electromagnetic data shows that the region that contributes to the response is a quasi-ellipsoid, which includes the source point and the receiving point. The strongest response stems from the source and the receiver’s surroundings; however, we can only measure the cross-well response. Outside the well area, there is a side-lobe of opposite polarity. In both cases with slender (two-dimensional) geologic features and increasing frequency, the contribution of the cross-well region to the response is significantly increased