Patent ID: 6459263
Filing Date: 2002-10-01
Classification: G01N,G01V

Abstract:
A method of determining a parameter of interest of a volume of earth formation surrounding a borehole with a borehole tool conveyed on a drilling tubular having a drill bit thereon for drilling the borehole, the method comprising:(a) using a magnet assembly on the borehole tool to produce a static magnetic field having a substantially uniform field strength in said volume of the formation; (b) using a plurality of sensors on the borehole to provide a motion signal indicative of motion of the tool in the borehole; (c) applying a predictive filter to the motion signal giving a predicted motion signal, (d) activating a transmitter on the borehole tool in response to said predicted motion signal to produce a radio frequency (RF) magnetic field having a direction substantially orthogonal to a direction of the static field in said volume of the formation, (e) measuring with the borehole tool signals induced by the RF field in the formation to give at least one measured signal; and (f) processing the at least one measured signal using a processor to determine the parameter of interest.