Influence of Axial Magnetic Interference on Wellbore Position Uncertainty

Abstract

Accompanied with the widespread application of complex wells such as cluster wells in the exploitation of oil and gas resources, it is becoming more and more important to reduce or accurately describe the size of the wellbore position uncertainty as much as possible. It is well known that axial magnetic interference affects azimuth measurement. In this paper, the correction method of axial magnetic interference in azimuth measurement and uncertainty ellipsoid calculation method considering axial magnetic interference correction are introduced, and the influence of axial magnetic interference correction on the position uncertainty of a horizontal well is analyzed through an example. The research shows that the influence of axial magnetic interference on wellbore position measurement error varies with measurement depth, and axial magnetic interference plays an increasing role in the influence of wellbore position measurement error. Therefore, well trajectory should be measured in an environment free of axial magnetic interference.