METHOD OF CORRECTING FOR AXIAL ERROR COMPONENTS IN MAGNETOMETER READINGS DURING WELLBORE SURVEY OPERATIONS

摘要

A method is provided for deriving wellbore azimuth in amanner which reduces the impact of axial magnetic field errors, whichutilizes a plurality of estimates of the axial component of the magnetic fieldwhich are combined in a manner which emphasizes the better estimatesand deemphasizes the poorer estimates.