Patent ID: 6646441
Filing Date: 2003-11-11
Classification: G01V

Abstract:
A electromagnetic wave propagation resistivity logging system comprising:(a) a tubular housing; (b) a plurality of transmitter-receiver groups axially spaced along said tubular housing and wherein (i) each said transmitter-receiver group comprises at least one transmitter assembly and two receiver assemblies, (ii) each said transmitter-receiver group is operated at two or more of three operating frequencies, and (iii) the lowest of said operating frequencies is within a range of about 20 kHz to about 100 kHz; (c) electronic circuitry for activating said at least one transmitter assembly in each said transmitter-receiver group and for recording induced signals in each said receiver assembly of each said transmitter-receiver group; and (d) a processor programmed to combining said recorded induced signals to yield a measure of resistivity of material in the vicinity of said tubular housing.