本文论述了全空间中矿体电阻率和形状对矿顶上视电阻率(ρ_s)异常值的作用规律,得到了一些有意义结论:视电阻率异常的饱和极限值出现的早晚与矿体形状有密切关系;对椭球状矿体而言,p_s异常值随矿体横截面的变化并非均为单调的增加或减小的简单关系,而有某个最佳几何特征参数时出现极大异常的规律。还讨论了利用镜像加倍法在对视电阻率和视极化率进行近似计算时,为避免产生严重错误应注意的参数选择界限问题,给出了一些有用列线图。 This paper discusses the law of the effect of the resistivity and shape of the orebody on the apparent resistivity (ρ_s) at the top of the mine in full space. Some meaningful conclusions are obtained: the saturation limit of apparent resistivity anomaly appears sooner or later and the shape of ore body Is closely related to the ellipsoid ore body, p_s anomalous value changes with the cross section of the ore body are not monotonous increase or decrease the simple relationship, and there is a certain geometric parameters of the greatest anomalies law. Some useful nomograms are also given for the parameter selection limits that should be noticed in order to avoid serious errors when the mirror image doubling method is used to approximate the apparent resistivity and apparent polarizability.