Linear System Description of the Electrical Parameters of Rocks

The electrical behavior of rocks exhibits a marked frequency dependence which has been difficult to interpret on a macroscopic scale except with resort to "abnormal" behavior. An important aspect of the interpretation of measurements is in the connection of measured quantities to the defined electrical parameters. This study utilizes a linear system analogy for a material having conductivity and permittivity which vary with frequency to show that 1) the electrical parameters for such a material must generally be considered complex functions of frequency, 2) that measurements yield only combinations of these parameters and, 3) that the complex formulation predicts, in a qualitative sense, the measured results.