WELL PLACEMENT UNCERTAINTY AND ASSESSMENT TECHNIQUES.
Kazimir V. Kovalenko – Cand.Tech.Sci., associate professor of the geophysical information systems department, the Gubkin State University of Oil and Gas, kazimirk@hotmail.com kazimirk@hotmail.com

УДК 550.832
Key words: measurement while drilling, directional surveys, ellipse of uncertainty,   error.

ОThe article focuses on mathematical tools for the construction of the ellipse of uncertainty of wellbore placement, which were approved by the international committee for wellbore survey accuracy   (ISCWSA), describes the differences in the combined effect of errors of magnetic surveys and gyro surveys, and shows the phases of geophysical modeling, which depends substantially on directional survey accuracy.

WELL PLACEMENT UNCERTAINTY AND ASSESSMENT TECHNIQUES.
Kazimir V. Kovalenko – Cand.Tech.Sci., associate professor of the geophysical information systems department,  the Gubkin State University of Oil and Gas, kazimirk@hotmail.com

Key words: measurement while drilling, directional surveys, ellipse of uncertainty,   error.

The article focuses on mathematical tools for the construction of the ellipse of uncertainty of wellbore placement, which were approved by the international committee for wellbore survey accuracy   (ISCWSA), describes the differences in the combined effect of errors of magnetic surveys and gyro surveys, and shows the phases of geophysical modeling, which depends substantially on directional survey accuracy.