The clays were treated as charged insulating nucle ous surrounded by a thin layer of electrolyte containing ionic The use of resistivity and the high-frequency dieletric logs for double layers. The behavior of this system is described bJ petrophysical interpretation of shaly sandstones is discussed complex electrical properties dependent on the particle di on basis of a simplified geophysical model for membrane mensions and its surface charge density, as well as on the polarization presented by Lima and Shaxma (1991, 1992).