Patent ID: 6600321
Filing Date: 2003-07-29
Classification: E21B,G01V

Abstract:
A Measurement-while-drilling (MWD) apparatus in a bottom hole assembly (BHA) for use in a borehole for obtaining a resistivity parameter of an earth formation penetrated by the borehole, the borehole having a substantially nonconducting fluid therein, the apparatus comprising:(a) at least one measure electrode carried on and rotating with a drilling tubular, said at least one measure electrode capacitively coupled to the earth formation through said nonconducting fluid, said at least one measure electrode conveying a measure current into the formation; and (b) a device responsive to least one of (i) the current in the at least one measure electrode, and, (ii) a voltage of the at least one measure electrode for producing a measure signal representative of the resistivity parameter.