Patent ID: 8499830

Claim:
A method of determining a casing point in an uncased interval of a well being drilled using a drilling mud, the method comprising: drilling a first uncased interval of the well with the drilling mud using a drill bit and drill string toward a region of interest in a subterranean formation without the drill bit entering the region of interest; measuring, during drilling in the first uncased interval of the well, resistivity in front of the drill bit; comparing the resistivity measured in front the of the drill bit to formation resistivity markers obtained during drilling of one or more offset well; determining, based on the comparison of the resistivity measured in front the of the drill bit to the formation resistivity markers, one or more casing points in the first uncased interval of the well while the drill bit advances toward but does not penetrate the region of interest while drilling the well; and casing the first uncased interval of the well based on the one or more casing points.