par DINU STEFANESCU
Institut de Pétrol, Gaz et Géologie, Bucarest, Romania
The distribution of stationary electric fields is determined for the case
of heterogeneous media in which the local conductivity 
varies according the law:
where Ri is the distance between the measuring point M and
the fixed "conductivitz
center"Si; Ci,Cii, and K are positive constants.
Considering that the number and position of the centers may be arbitrary chosen,
these theoretical models of heterogeneous media allow to calculate in advance
the results of the measurements obtainable from various devices of d.c. electrical
prospecting. They also allow to appareciate the efficiency of the usual procedures
of graphical presentation of these results.