在阶跃圆电流激发下球形地质体的瞬变电磁响应

对被均匀导电介质包围的球形地质体的瞬变电磁响应作了解析研究。激发场源为通有阶跃电流的圆形回路，在轴对称条件下，建立起关于德拜位的偏微分方程，直接在时间域用分离变量法求解，得出了解析解。给出了几种特殊情形下的解式，还得出了在导电球体被弱导电介质包围条件下的近似解式。

THE TRANSIENT ELECTROMAGNETIC RESPONSE OF A SPHERICAL GEOLOGIC BODY EXCITED BY A STEP CURRENT FLOWING IN A CIRCULAR LOOP

in this paper, the author has investigated the transient electromagnetic response of a spherical geologic body embedded in an uniform conducting medium. The excitation source is a step current flowing in a circular loop. Under the axially symmetric conditions, the partial differential equations are set up. The analytic expression of solution is obtained directly in the time domain by means of separating variables. Some solutions for special situations are given. Moreover, the approximate solution for the conducting spherical body in a weak conducting environment has been obtained.