This article addresses the important challenge of ensuring accurate inclinometer measurements during the construction of directional and horizontal wells in the Far North and Arctic shelf of Russia. In these regions, traditional inclinometer methods based on accelerometers and magnetometers face significant challenges due to significant changes in the geomagnetic field (magnetic storms, secular variations, and other disturbances). Wellbore azimuth measurement errors due to geomagnetic field distortions lead to risks of deviation from the planned trajectory, resulting in financial and techno-logical losses. A detailed analysis has been conducted and requirements for the use of up-to-date geomagnetic data and high-precision mathematical models have been formulated, providing the basis for correcting inclinometer measurements during horizontal drilling at critical latitudes. It is not enough to use outdated or global models (IGRF) in order to compensate for external magnetic disturbances in the Arctic: local, regularly updated high-resolution models (similar to HRGM, IFR-1, IFR-2), taking into account the regional particularities and local lithospheric magnetic anomalies, are needed. The national geomagnetic models (CAMPUS-C, CAMPUS-A, CAMPUS-CA, DIF-1), developed by the Geophysical Center of the RAS and the Institute of Petroleum Geology and Geophysics SB RAS for the oil and gas industry, are presented, and for the first time their applicability as a replacement for foreign models (BGGM/HDGM) for directional drilling tasks in the Arctic conditions is substantiated. The new national geomagnetic models and a detailed justification for the optimal number and location of geomagnetic observatories necessary to ensure reliable monitoring of the magnetic environment are proposed. The application of such specialized models and data helps mitigate the effects of geomagnetic interference, ensuring reliable determination of the drilling tool's spatial position during horizontal drilling. This helps optimize drilling processes and improve the safety and efficiency of Arctic field development, which is of strategic importance for the Russian Federation.
