Overview
Deep well drilling is sometimes more importantly characterized by the requirement of having the drill bit finally positioned within a specified radius of its surface starting location. This sometimes requires maneuvering the direction (azimuth) of the drill bit by various techniques (kicking) so as to arrive at the desired location at both the desired depth and within a specified radius of the starting point. The angle of drilling at any arbitrary azimuth can be derived by knowing the TVD (true vertical depth) and the MD (measured depth or hypotenuse) of any given segment.
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