Patent Document ID: 20070061080
Application ID: 11492221
Patent Flag: 0

Claim One:
1. A method of identifying underground formations, comprising the steps of: a) acquiring electromagnetic data using electromagnetic (EM) receivers to measure EM data responses in an EM field which passes through an underground formation, said EM data responses being either in frequency or in time domain; b) determining an observed effective complex conductivity of the underground formation as a function of position and frequency or time using a 3-D EM inversion technique; c) transforming said observed effective complex conductivity into a conductivity relaxation model as a function of position and frequency or time using an analytical expression of theoretical effective conductivity, said analytical expression being a multi-phase physical and mathematical model of a composite medium; d) determining intrinsic physical and geometrical parameters of the composite medium using the analytical expression, said parameters including at least one of: conductivity contrast between different phases of the medium, size and volume of inclusions; e) determining percent content of constituent portions of the composite medium as a function of a position within the underground formation; and f) correlating said parameters with known geological formations.